DE102013104514A1 - Method for operating hybrid vehicle power train, involves adjusting torque output of starter or generator integrated into power train in reaction on difference between desired and actual power train rotational torques - Google Patents

Abstract

The method involves adjusting a torque output of a starter (96) or generator integrated into a power train in reaction on a difference between a desired power train rotational torque and an actual power train rotational torque during partial closing of a power train separation clutch. A power train separation clutch torque is estimated in an open loop based on a power train separation clutch operation command. An engine (10) is started by supplying fuel and an ignition spark to the engine before the power train separation clutch is completely closed. The desired power train rotational torque is a desired torque converter impeller rotational torque. The actual power train rotational torque is an actual torque converter impeller rotational torque. An independent claim is also included for a hybrid vehicle power train system.

Description

Cross-reference to related applications

The present application claims priority to United States provisional patent application 61/643134, filed May 4, 2012, the entire contents of which are hereby incorporated by reference for all purposes.

area

The present description relates to a system and methods for improving the driveability and fuel economy of a vehicle. The methods may be particularly useful for power machines that are selectively coupled to an electric machine and a transmission.

Background and abstract

Some hybrid vehicles may include a driveline disconnect clutch that may be opened and closed to mechanically isolate an engine from a transmission. The driveline disconnect clutch may also isolate the engine from an electric machine in the driveline. The driveline disconnect clutch may be closed to increase the output of the driveline. The driveline disconnect clutch may be opened to reduce driveline inertia and allow the engine to stop rotation so fuel can be saved. However, the driveline disconnect clutch may wear over time, and differences may exist between powertrain clutches of various vehicles. Thus, an actuation force or pressure at which the driveline disconnect clutch begins to transmit torque may vary. Furthermore, torque transmitted between the driveline disconnect clutch via a clutch stroke may also differ between vehicles. Therefore, it may be difficult to mitigate driveline torque disturbances that may be caused by closing the driveline disconnect clutch.

The inventors herein have recognized the above-mentioned disadvantages and have developed a method of operating a hybrid vehicle driveline comprising: adjusting a driveline integrated starter / generator (DISG) torque output in response to a difference between a desired driveline torque and a driveline torque actual driveline torque during at least partially closing a driveline disconnect clutch.

By adjusting the operation of a DISG in response to a difference between a desired driveline torque and an actual driveline torque during the closure of a driveline disconnect clutch, it may be possible to provide a desired driveline torque. For example, the torque output of a DISG may be adjusted in response to a torque sensor output during the closing of the driveline disconnect clutch such that the driveline torque corresponds to a desired driveline torque even during the closing of a driveline disconnect clutch. Thus, the torque sensor provides driveline torque feedback for driveline disconnect actuation error compensation.

The present description can provide several advantages. In particular, the approach can improve driveline torque delivery. Furthermore, the approach can improve compensation for an impaired driveline disconnect clutch. In addition, the approach may allow many vehicles having different driveline disconnect clutches to operate in a similar manner.

The above advantages and other advantages and features of the present description will be readily apparent from the following detailed description alone or in conjunction with the accompanying drawings.

Of course, the above summary is provided to introduce a selection of concepts that are further described in the detailed description in a simplified form. It is not meant to identify key or essential features of the claimed subject matter, the scope of which is defined only by the claims which follow the detailed description. Furthermore, the claimed subject matter is not limited to implementations that solve any disadvantages noted above or in any part of this disclosure.

Brief description of the drawings

The advantages described herein are more fully understood by reading an example of an embodiment, which is hereby described in detail, solely or with reference to the drawings, in which:

1 is a schematic diagram of an engine;

2 shows a first example vehicle powertrain configuration;

3 shows a second example vehicle powertrain configuration;

4 Fig. 10 is a flowchart showing an example of operating a vehicle driveline with the methods described in the following figures;

5 - 8th Show flowcharts and conditions for operating a hybrid vehicle driveline in response to driving route conditions;

9 and 10 show a method and an anticipated sequence for adjusting powertrain operation in response to vehicle mass;

11 and 12 show a method and an anticipated sequence for starting a hybrid vehicle;

13 and 14 show a method and anticipated sequence for adjusting the fuel for a hybrid powertrain during engine starting;

15 - 18 Show methods and anticipated sequences for starting an engine of a hybrid vehicle during transmission shifting;

19 - 22 Show methods and anticipated sequences for providing flywheel and driveline disconnect clutch compensation;

23 - 26 Show methods and anticipated sequences for stopping an engine of a hybrid vehicle;

27 and 28 show a method and an anticipated sequence for holding a hybrid vehicle with a stopped engine on a hill;

29A - 36 Show methods and anticipated sequences for operating a hybrid powertrain with driveline braking;

37 - 40 Show methods and anticipated sequences for operating a hybrid powertrain in a sailing mode;

41 - 44 Show methods and anticipated sequences for adjusting the driveline disconnect operation; and

45 - 48 show anticipated functions for describing or modeling a transmission torque converter.

Detailed description

The present description relates to controlling a powertrain of a hybrid vehicle. The hybrid vehicle may include an engine and an electric machine as in 1 - 3 shown. The engine may be operated with or without the driveline integrated starter / generator (eg, an electric machine or an electric motor that may be abbreviated DISG (driveline integrated starter / generator)) during vehicle operation. The driveline integrated starter / generator is integrated with the driveline on the same axis as the engine crankshaft and rotates as the torque converter impeller rotates. Furthermore, the DISG can not be selectively engaged or disengaged with the driveline. Rather, the DISG is an integral part of the powertrain. Still further, the DISG may be operated with or without operating the engine. The mass and inertia of the DISG remain with the driveline when the DISG is not operating to deliver or absorb torque to the driveline.

The driveline may according to the method of 4 operate. In some examples, the driveline may be operated based on a driving route and the vehicle mass, as in FIG 5 - 10 described. The engine can according to the in the 11 to 18 to be started. A driveline component compensation may be provided, as in FIG 19 - 22 described. Fuel can be saved by selectively stopping the engine, as in 23 - 28 described. The driveline may also enter a regeneration mode, as in FIG 29A - 36 described in which the kinetic energy of the vehicle is converted into electrical energy. The electrical energy can then be used to power the vehicle. During some conditions, the vehicle powertrain may enter a sailing mode in which the engine is operated, but is not mechanically coupled to the DISG or the transmission or vehicle wheels, as in FIG 37 - 40 described. The operation of the driveline disconnect clutch can be adjusted as in 41 to 44 shown. The methods described herein can be used together at the same time to operate in a system that performs multiple methods. Finally show 45 - 47 anticipated functions to describe a transmission torque converter.

Regarding 1 becomes an engine 10 with internal combustion with several cylinders, one cylinder of which in 1 shown by an electronic engine control unit 12 controlled. The engine 10 includes a combustion chamber 30 and cylinder walls 32 where a piston 36 is arranged therein and with a crankshaft 40 connected is. A flywheel 97 and a ring gear 99 are with the crankshaft 40 coupled. A starter 96 includes a pinion shaft 98 and a pinion 95 , The pinion shaft 98 can selectively the pinion 95 advance it to the ring gear 99 to engage. The starter 96 can be mounted directly on the front of the engine or on the back of the engine. In some examples, the starter 96 selectively a torque to the crankshaft 40 deliver via a belt or a chain. The starter 96 can be described as starting device with lower power. In one example is the starter 96 in a base state when it is not engaged with the engine crankshaft. The combustion chamber 30 is with an intake manifold 44 and an exhaust manifold 48 via a respective inlet valve 52 and exhaust valve 54 shown in connection. Each intake and exhaust valve can pass through an intake cam 51 and an exhaust cam 53 be operated. The position of the intake cam 51 can through an inlet cam sensor 55 be determined. The position of the exhaust cam 53 can through an exhaust cam sensor 57 be determined.

A fuel injector 66 is for injecting fuel directly into the cylinder 30 which is known to those skilled in the art as direct injection. Alternatively, fuel may be injected into an intake passage, which is known to those skilled in the art as port injection. The fuel injector 66 supplies liquid fuel in proportion to the pulse width of a signal FPW from the control unit 12 , The fuel is supplied to the fuel injector by a fuel system (not shown) having a fuel tank, a fuel pump, and a fuel rail (not shown) 66 fed. The fuel injector 66 is powered by operating current from the driver 68 supplied to the control unit 12 responding. In addition, the intake manifold 44 with an optional electronic throttle 62 shown in connection, which is a position of a throttle plate 64 adjusts the air flow from the air inlet 42 to the intake manifold 44 to control. In one example, a low pressure direct injection system may be used wherein the fuel pressure may be increased to about 20-30 bar. Alternatively, a high pressure dual stage fuel system may be used to generate higher fuel pressures. In some examples, the throttle may 62 and throttle plate 64 between the inlet valve 52 and the intake manifold 44 be arranged so that the throttle 62 a duct throttle is.

A distributorless ignition system 88 provides a spark to the combustion chamber 30 over a spark plug 92 in response to the control unit 12 , A universal exhaust gas oxygen sensor (UEGO sensor, universal exhaust gas oxygen sensor) 126 is with the exhaust manifold 48 upstream of a catalyst 70 shown coupled. Alternatively, the UEGO sensor 126 be exchanged for an exhaust oxygen sensor with two states.

The catalyst 70 may include multiple catalyst building blocks in one example. In another example, multiple emission control devices may each be used with multiple building blocks. The catalyst 70 may be a three-way catalyst, a particulate filter, a lean NOx trap, a selective reduction catalyst, or another emission control device. An exhaust gas purifier heater 119 may also be located in the exhaust system to the catalyst 70 and / or to heat exhaust gases.

The control unit 12 is in 1 as a conventional microcomputer, comprising: a microprocessor unit 102 , Input / output ports 104 , a read-only memory 106 , a random access memory 108 , a hold 110 and a conventional data bus. The control unit 12 is different signals from sensors connected to the engine 10 in addition to the previously discussed signals, including: Engine coolant temperature (ECT) from the temperature sensor 112 that with a cooling sleeve 114 is coupled; a position sensor 134 that with an accelerator pedal 130 coupled to capture the by a foot 132 applied force and / or position; a position sensor 154 with the brake pedal 150 coupled to capture the by a foot 152 applied force and / or position; a measurement of engine manifold pressure (MAP) from the pressure sensor 122 that with the intake manifold 44 is coupled; an engine position sensor of a Hall effect sensor 118 , which is the position of the crankshaft 40 detected; a measurement of entering the engine air mass from the sensor 120 ; and a measurement of the throttle position from the sensor 58 , The air pressure may be for processing by the control unit 12 also be detected (sensor not shown). In a preferred aspect of the present description, the engine position sensor generates 118 a predetermined number of equally spaced pulses each revolution of the crankshaft from which the engine speed (RPM) can be determined.

In some examples, the engine may be coupled to an electric motor / battery system in a hybrid vehicle, as in FIG 2 and 3 shown. Further, in some examples, other engine configurations may be used, such as a diesel engine.

During operation, each cylinder inside the engine 10 typically undergoes a four-stroke cycle: the cycle includes the intake stroke, the compression stroke, the expansion stroke and the exhaust stroke. During the intake stroke, the exhaust valve generally closes 54 and the inlet valve 52 opens. Air gets over the intake manifold 44 into the combustion chamber 30 introduced and the piston 36 moves to the bottom of the cylinder to keep the volume inside the combustion chamber 30 to enlarge. The position in which the piston 36 near the bottom of the cylinder and at the end of its stroke (for example, when the combustion chamber 30 at its largest volume) is typically referred to by those skilled in the art as bottom dead center (BDC). During the compression stroke, the inlet valve 52 and the exhaust valve 54 closed. The piston 36 moves in the direction of the cylinder head to the air inside the combustion chamber 30 to compress. The point where the piston is 36 at the end of its stroke and closest to the cylinder head (eg, when the combustion chamber 30 is at its smallest volume) is typically referred to by those skilled in the art as top dead center (TDC). In a process, hereinafter referred to as injection, fuel is introduced into the combustion chamber. In a process, hereinafter referred to as ignition, the injected fuel by a known ignition means such as. As a spark plug 92 ignited, which leads to combustion. During the expansion stroke, the expanding gases push the piston 36 back to the BDC. The crankshaft 40 converts the piston movement into a torque of the rotary shaft. During the exhaust stroke, the exhaust valve will eventually open 54 to the burnt air / fuel mixture to the exhaust manifold 48 and the piston returns to the TDC. It should be noted that the above is shown by way of example only and that the intake and exhaust valve opening and / or closing timings may vary, such as, for example, FIG. B. to provide a positive or negative valve overlap, a late intake valve closing or various other examples.

2 is a block diagram of a vehicle driveline 200 in a vehicle 290 , The drive train 200 can through the engine 10 are driven. The engine 10 can with a in 1 shown engine start system or via the DISG 240 to be started. Furthermore, the engine can 10 a torque via a torque actuator 204 such as As a fuel injector, a throttle, etc. produce or set.

Engine output torque may go to an input side of a dual mass flywheel 232 be transmitted. The engine speed and the dual mass flywheel input side position and speed may be determined via the engine position sensor 118 be determined. The dual mass flywheel 232 may include springs and separate masses (not shown) for damping driveline torque disturbances. The output side of the dual mass flywheel 232 is with the input side of a driveline disconnect clutch 236 shown mechanically coupled. The driveline disconnect clutch 236 can be operated electrically or hydraulically. A position sensor 234 is on the driveline disconnect clutch side of the dual mass flywheel 232 arranged to the home position and speed of the dual-mass flywheel 232 capture. In some examples, the position sensor 234 comprise a torque sensor. The downstream side of the driveline disconnect clutch 236 is with the DISG input shaft 237 shown mechanically coupled.

The DISG 240 Can be operated to drive torque to the driveline 200 or to convert a driveline torque into electrical energy stored in an electrical energy storage device 275 should be saved. The DISG 240 has an output power greater than that of in 1 shown starters 96 , Furthermore, the DISG is driving 240 directly the drive train 200 or directly from the powertrain 200 driven. There are no straps, gears, or chains available to the DISG 240 with the drive train 200 to pair. Rather, the DISG revolves 240 at the same rate as the powertrain 200 , The electrical energy storage device 275 may be a battery, a capacitor or an inductor. The downstream side of the DISG 240 is with the impeller 285 of the torque converter 206 over a wave 241 mechanically coupled. The upstream side of the DISG 240 is with the driveline disconnect clutch 236 mechanically coupled.

The torque converter 206 includes a turbine wheel 286 to apply torque to the input shaft 270 issue. The input shaft 270 couples the torque converter 206 mechanically with an automatic transmission 208 , The torque converter 206 also includes a torque converter lock-up clutch 212 (TCC, torque converter bypass lock-up clutch or short torque converter clutch). A torque is directly from the impeller 285 to the turbine wheel 286 transmitted when the TCC is locked. The TCC is controlled by the control unit 12 electrically operated. Alternatively, the TCC can be hydraulically locked. In one example, the torque converter may be referred to as a component of the transmission. The torque converter impeller speed and position may be via the sensor 238 be determined. The torque converter turbine speed and position can be controlled via the position sensor 239 be determined. In some examples 238 and or 239 Torque sensors may be or may be a combination of position and torque sensors.

When the torque converter clutch 212 is completely disengaged transmits the torque converter 206 an engine torque to the automatic transmission 208 via fluid communication between the torque converter turbine wheel 286 and the torque converter impeller 285 , whereby a torque multiplication is possible. In contrast, when the torque converter clutch 212 is fully engaged, the engine output torque directly via the torque converter clutch to an input shaft 270 of the transmission 208 transfer. Alternatively, the torque converter clutch 212 partially engaged, thereby allowing the amount of torque transmitted directly to the transmission to be adjusted. The control unit 12 It can be configured to set the amount of torque produced by the torque converter 206 is transmitted by adjusting the torque converter clutch 212 in response to various engine operating conditions or on the basis of an engine operating request based on a driver.

The automatic transmission 208 includes speed clutches (eg gears 1-6) 211 and a forward clutch 210 , The speed clutches 211 and the forward clutch 210 can be selectively engaged to power a vehicle. That from the automatic transmission 208 Torque output can turn to the wheels 216 be forwarded to the vehicle via the output shaft 260 drive. The output shaft 260 provides torque from the transmission 308 to the wheels 216 about the differential 255 that's a first gear 257 and a second gear 258 includes. The automatic transmission 208 may be an input drive torque at the input shaft 270 in response to a vehicle driving condition prior to transmitting output drive torque to the wheels 216 transfer.

Furthermore, a frictional force on the wheels 216 by engaging wheel friction brakes 218 be applied. In one example, the wheel friction brakes 218 in response to the driver stepping on a brake pedal (not shown) with his foot. In other examples, the control unit may 12 or one with the control unit 12 linked control unit apply the engagement of the wheel friction brakes. In the same way, by disengaging the wheel friction brakes 218 in response to the driver releasing his foot from a brake pedal, a friction force for the wheels 216 be reduced. Further, the vehicle brakes can apply a frictional force to the wheels 216 via the control unit 12 as part of an automated engine stop procedure.

A mechanical oil pump 214 can with the automatic transmission 208 in fluid communication to a hydraulic pressure to engage various couplings such. B. the forward clutch 210 , the gear clutches 211 and / or the torque converter clutch 212 to deliver. The mechanical oil pump 214 can according to the torque converter 206 can be operated and, for example, by the rotation of the engine or the DISG via the input shaft 241 are driven. Consequently, in the mechanical oil pump 214 generated hydraulic pressure increase as an engine speed and / or DISG speed increases, and may decrease as engine speed and / or DISG speed decreases.

The control unit 12 may be configured to inputs from the engine 10 to receive, as in 1 shown in greater detail, and thus to control an output torque of the engine and / or the operation of the torque converter, the transmission, the DISG, the clutches and / or brakes. As an example, engine output torque may be controlled by adjusting a combination of spark timing, fuel pulse width, fuel pulse timing, and / or air charge, throttle valve opening and / or valve timing, valve lift, and turbocharged or supercharged engine supercharging. In the case of a diesel engine, the control unit 12 controlling engine output torque by controlling a combination of fuel pulse width, fuel pulse timing, and air charge. In all cases, engine control may be performed on a cylinder-by-cylinder basis to control engine output torque. The control unit 12 may also control the output torque and the generation of electrical energy from the DISG by adjusting the current flowing to and from the DISG windings, as known in the art.

If idle stop conditions are met, the control unit may 12 initiate engine shutdown by shutting off the fuel and spark for the engine. However, the engine may continue to turn in some examples. To maintain a lot of torsion in the transmission, the control unit can 12 Furthermore, rotary elements of the transmission 208 on a housing 259 of the transmission and thereby fixed to the frame of the vehicle to ground. In particular, the control unit 12 one or more transmission clutches such. B. the forward clutch 210 engage and engage the engaged transmission clutch (s) on the transmission housing 259 and vehicle frame as described in U.S. Patent Application No. 12 / 833,788, "METHOD FOR CONTROLLING TO ENGINE THAT MAY BE AUTOMATICALLY STOPPED", which is hereby fully incorporated by reference in all respects. A transmission clutch pressure may be varied (eg, increased) to adjust the engagement state of a transmission clutch and to provide a desired amount of transmission torsion.

A wheel brake pressure may also be adjusted during engine shutdown based on the transmission clutch pressure to assist in mooring the transmission while reducing torque transmitted through the wheels. By applying the wheel brakes 218 In particular, while one or more engaged transmission clutches are locked, opposing forces may be applied to the transmission and, consequently, to the driveline, thereby actively maintaining the transmission gears and maintaining potential torsional energy in the transmission gear set without moving the wheels. In one example, the wheel brake pressure may be adjusted to coordinate the application of the wheel brakes to the locked gear clutch during engine shutdown. As such, by adjusting the wheel brake pressure and clutch pressure, the amount of torsion retained in the transmission when the engine is shut down can be adjusted.

If restart conditions are met and / or a vehicle driver wants to start the vehicle, the control unit may 12 Reactivate the engine by resuming combustion in the cylinders. As further related to 11 - 18 Further elaborated, the engine can be started in a variety of ways.

The vehicle 290 can also have a windshield heater 294 and a rear window heater 292 include. The disk heaters 294 and 292 can be operated electrically and in the front and rear windows 295 and 293 embedded or coupled with the vehicle. The vehicle 290 can also lights 296 include, which may or may not be visible to the driver while the driver is the vehicle 290 operates. The vehicle 290 can also be an electrically operated fuel pump 299 include, the fuel to the engine 10 during selected conditions. Finally, the vehicle can 290 an electric heater 298 which selectively heat to air in a vehicle cabin or ambient air outside the vehicle 290 supplies.

Regarding 3 a second example vehicle powertrain configuration is shown. Many of the elements in the powertrain 300 are similar to the elements of the powertrain 200 and use similar reference numerals. Therefore, for the sake of brevity, the description of elements between 2 and 3 are common, waived. The description of 3 is limited to elements of the elements of 2 are different.

The drive train 300 Includes a dual-clutch double countershaft transmission 308 , The gear 308 is essentially an automatically operated manual transmission. The control unit 12 actuates the first clutch 310 , the second clutch 314 and a switching mechanism 315 to move between courses (eg 1st to 5th gear) 317 select. The first clutch 310 and the second clutch 314 can be selectively opened and closed between the aisles 317 to switch.

The systems of 1 - 3 may include torque sensors, which may be the basis for adjusting driveline operation. Alternatively, the torque converter itself may be used as a torque sensor when the torque converter clutch 212 completely disengaged. In particular, the torque output of an open torque converter is a function of the input and output speeds, impeller and turbine speeds, where the impeller is the torque converter input and the turbine is the torque converter output. In the application of 2 / 3 For example, the impeller speed equals the measured DISG speed since the DISG rotor output shaft is the impeller input shaft, and the turbine speed is measured and used in the control of the transmission clutch control.

In addition, in view of an input and output speed characterization of the open torque converter, the output torque of the open torque converter may be adjusted by controlling the torque converter impeller speed as a function of torque converter turbine speed to be controlled. The DISG may be operated in a speed feedback mode to control the torque converter torque. For example, the commanded DISG speed (eg, same as the torque converter impeller speed) is a function of the torque converter turbine speed. The commanded DISG speed may be determined as a function of both the DISG speed and the turbine speed to provide the desired torque at the torque converter output.

Driveline disorders in the systems of 1 - 3 can also be reduced via the driveline disconnect clutch. An example method opens the torque converter clutch prior to operating the driveline disconnect clutch. For example, the driveline disconnect clutch may be opened when the engine is commanded to shut down, either during a regenerative braking condition of the vehicle and / or when the vehicle comes to a stop and the engine is shut down.

In another example, during regenerative braking, the driveline disconnect clutch may be open, the engine may be stopped, and the torque converter may be locked to increase the brake torque that is in the DISG 240 can be absorbed. After the engine is shut down, the driveline disconnect clutch remains open until the beginning of the engine restart process. During the engine restart, the driveline disconnect clutch may be partially closed to the first combustion event in a cylinder to start the engine. Alternatively, the driveline disconnect clutch may be partially closed until the engine reaches a predetermined speed after combustion in a cylinder is initiated. Once the engine combustion is sufficiently restarted and the engine and driveline disconnect clutch speeds are sufficiently close (eg, within a threshold speed value), the capacity of the driveline disconnect clutch to close and hold without slip is increased. During the driveline disconnect clutch increase, torque disturbances may be present at the driveline disconnect clutch output. Thus, torque feedback from the open torque converter or a torque sensor may be the basis for setting a DISG speed setting. Operating the DISG in a speed control mode may allow desired more consistent torque values to be maintained until the driveline disconnect clutch is fully closed. After the driveline disconnect clutch is closed, the torque converter clutch (TCC) may be locked based on a lockout scheme (eg, the TCC may be actuated based on accelerator pedal position and vehicle speed).

In this way, the torque converter clutch may be fully opened prior to the start of the engine restart process. The torque converter clutch may be closed after the engine has restarted and the driveline disconnect clutch has fully closed. In addition, while the driveline disconnect clutch is being closed, the pressure on the driveline disconnect clutch is known (as commanded by the controller), and thereby provides an estimate of the average driveline disconnect clutch torque. To further improve operation, this estimation of driveline disconnect clutch torque or driveline disconnect clutch capacity may be used by the control unit as the mid-coupling input to the DISG feedback speed control to enhance the interference suppression response. The driveline disconnect clutch capacity based on a torque estimate may then be added as input to an internal torque feedback loop in the electric machine (DISG). The inner loop is an inner current loop that may be the basis for improving the response of the DISG when the DISG is in the speed feedback mode.

In this way, an example method of operating a vehicle having a powertrain, such as a power train, includes: B. with regard to 2 - 3 described powertrain first operating with the vehicle stopped or at a speed below a threshold and with the engine at rest and the open driveline disconnect clutch. When the torque converter is fully unlocked, the method next includes receiving a request to start the vehicle, such as a vehicle. On the basis of a driver pedal input that increases beyond a threshold amount. In response, the engine is started and with one or more of the DISG 240 and a starter motor is started while the driveline disconnect clutch is closed, again with the torque converter still unlocked. During this process, torque feedback from the torque converter input / output speed is used to torque the shaft 241 which is compared to a desired torque value, and provides adjustment to a speed setting of the DISG 240 which is in the speed control mode. The speed setting may be, for example, a setting parameter that detects a torque error between the estimated and the desired torque on the shaft 241 towards zero.

In addition to the above process, additional control actions may be taken, particularly with regard to game traversal. For example, when the driver depresses the accelerator pedal while the vehicle is in an engine-off regeneration mode (eg, at rest), the driveline transitions from negative torque to positive torque, the engine is started, and the driveline disconnect clutch closes All of these actions are coordinated to introduce minimal torque disturbances to the wheels. Under selected conditions, these actions are performed while the transmission 208 in a fixed gear (eg without changing the gear) is held. However, starting the engine and traversing the game can create such disturbances. As such, during driveline, the driveline torque may be controlled from a small negative to a small positive torque during the game traversal and then to the requested torque. However, such a limitation of engine torque may introduce a delay in providing the driver's requested torque, which, when added to retard the restart of the engine, may cause significant driver dissatisfaction.

In one method, a coordination of the capacity of the torque converter lock-up clutch 212 and the outcome of the DISG 240 be used. The timing of the implementation of the DISG from the torque control to the speed control may be adjusted, for example, to engine restart conditions and the transition through the play area to reduce driveline disturbances caused by the engine start and traversal of the play area.

In one example, an operation is provided for conditions under which the driver applies the brake and the vehicle is in a regeneration mode, the engine is off, the driveline disconnect clutch is fully open, and the DISG is absorbing torque. The DISG generates the desired level of braking torque (and stores the generated electricity in, for example, the battery). During these conditions, the driveline is subjected to a negative torque and the torque converter lockup clutch 212 is locked. The amount of negative torque on the DISG can be increased and applied by the driveline to enhance regeneration. The amount of negative torque may be based on a desired wheel braking torque for the present operating conditions. The negative braking may be based on a degree in which the driver applies a brake. However, the negative braking may also occur while the driver has released both the brake pedal and the accelerator pedal.

When the driver releases the brake (when applied) and steps on the accelerator pedal, the vehicle enters engine-on operation, with positive driveline torque providing a requested torque level. As indicated above, during this transition without gear change, the torque passes through the zero torque (play zone) and the engine is started and started. The inventors have recognized here that the engine cranking torque disturbance is upstream of the clutch 212 but the play disorder is downstream of the clutch 212 lies. The capacity of the clutch 212 can be coordinated with the speed of the DISG to reduce these driveline disturbances.

The capacity of the TCC 212 For example, it may be reduced sufficiently to allow controlled slippage as the regeneration torque is reduced. Such operation may help to isolate the driveline from the engine cranking torque disturbance. As the DISG regeneration torque transitions from the current value to zero torque, the driveline may transition from a large negative torque to near zero torque. Near the zero torque, the driveline may enter the play area. The control of the DISG is then switched from the torque control mode to the speed control mode and the torque converter impeller speed (Ni) is set to a fixed speed above the torque converter turbine speed (Nt).

Adjusting the torque converter impeller speed in this manner provides a small positive torque during the traversing of the play area and reduces the disturbance to the driveline associated with traversing the play area. The desired DISG speed may be increased to provide torque to the wheels and provide some vehicle acceleration. An estimate of the amount of torque required to start the engine may be determined by the controller to provide a positive feedback DISG torque command. The positive feedback DISG torque command can cause speed disturbances on the torque converter impeller decrease when the driveline disconnect clutch is engaged and the engine is started. The capacity of the driveline disconnect clutch is adjusted to reduce driveline interference. Once the engine has started and the driveline disconnect clutch is closed, the engine may be transitioned into torque control and provide the desired torque.

As above, here with regard to the system of 1 - 3 For example, torque disturbances may occur when the driveline disconnect clutch is actuated. Torque disturbances can lead to degraded handling and NVH. Torque disturbances (eg, due to a clutch actuation fault or clutch slip, or a fault between the commanded and actual engine torque) at the driveline disconnect clutch output may be transmitted to the transmission input and to the wheels as a function of the transmission clutch state (eg, degree of engagement of the driveline disconnect clutch, such as, for example). Based on the pressure or slip ratio) and the gear ratio.

That through the DISG 240 generated torque may be a function of a three-phase current in some examples. The torque at the DISG output shaft 241 is a sum of the DISG output torque and the torque at the input of the DISG or electric machine. The DISG may be powered by a powertrain control module (eg, the control unit 12 ) are commanded to operate in either a speed feedback mode or a torque mode. The control unit provides the commanded speed or commanded torque. The controller or inverter uses the feedback of either the DISG speed sensor or the DISG current to produce the desired speed or torque.

For example, the DISG torque may be output from a function or table that empirically includes values of DISG torque based on the DISG speed and the DISG current. In some constructions, the DISG output is connected to a launch clutch that is modulated during shift events to shape or smooth the output torque of the DISG before it is transmitted to the wheels. In other applications, the DISG output is with a torque converter 206 connected to a lock-up clutch. In designs that use a launch clutch instead of a torque converter, the ability of the launch clutch to precisely and quickly control clutch torque at low torque levels may be challenging. For example, the starting clutch may grind in the presence of the maximum output torque of the engine plus DISG. Therefore, the starting clutch can be designed with a high torque capacity. However, it may be difficult to accurately control the starting clutch at low torque levels that may be used during zero and / or low vehicle speeds during engine restart and during vehicle startup.

One method of adjusting or controlling a starting clutch is to use a torque sensor mounted on the starting clutch input shaft. The torque sensor installation deposits a shaped magnetic layer on the starting clutch input shaft which produces an output voltage that is proportional to the shaft torque. The voltage is read by contactless sensor (s) and detection system. The torque signal from the torque sensor may then be used to operate the DISG in a closed loop torque feedback mode to cancel torque disturbances appearing at the driveline disconnect clutch output (DISG input). When the automatic transmission uses a torque converter clutch on the transmission input, a torque sensor may be attached to the torque converter input shaft. The torque converter input shaft torque sensor may be used to provide feedback in the DISG control unit to suppress torque disturbances transmitted by the driveline disconnect clutch.

As described herein, the engine may be shut down to zero speed (and the driveline disconnect clutch opened) to reduce fuel consumption when the driver releases the accelerator pedal. The engine is therefore shut down when the vehicle comes to a stop or at another time when the torque from the DISG is sufficient to accelerate the vehicle or to overcome the road load. When the driver applies the accelerator pedal and the desired torque exceeds that which the DISG can provide, the engine is restarted to supplement the DISG output torque. Additionally, the engine may be restarted during a coasting condition when the battery state of charge falls below a minimum threshold. The engine may be restarted to provide positive driveline torque and provide torque to allow the DISG to operate as a generator to recharge the battery. During the Engine restart process, depending on the operating conditions, either the driveline disconnect clutch or a separate starter motor may be used to start the engine as described herein. Once combustion begins in the engine, either the engine is accelerated to match the input speed of the DISG or the driveline disconnect clutch / slip is controlled by controlling the clutch pressure to pull the engine up to the DISG input speed. When the driveline disconnect clutch closes, a large torque disturbance may be generated at the driveline disconnect clutch output, which may then be transmitted to the DISG output. A torque disturbance can potentially be transmitted around the transmission output and to the wheels, thereby degrading vehicle handling and NVH.

Various methods may be used to reduce the impact of this engine restart torque disturbance, such as: For example, those already described here. Alternatively or additionally, one method of reducing the amplitude of the engine restart torque disturbance at the driveline disconnect clutch output is to adjust the engine crankshaft speed to the driveline disconnect clutch output or DISG speed (since the two are connected by a shaft) before the driveline disconnect clutch is closed. One such method makes use of the differential relationship of the driveline disconnect clutch output torque to the driveline disconnect clutch speed. In particular, the driveline disconnect clutch output torque is effectively multiplied by the sign of the driveline disconnect clutch input and output speed difference. For example, it is approximately equal to sign (crankshaft speed - DISG speed). The closer these speeds are adjusted, the lower the driveline disconnect clutch output torque.

Although such a method may be used to reduce the driveline disconnect clutch output torque disturbance, it operates to accelerate engine speed to the driveline disconnect clutch output speed. The driveline disconnect clutch output ^speed may vary from 750 to 3000 RPM. Acceleration of the engine to a speed in this range may delay engine-powered startup and driver response to accelerator pedaling. For example, until the driveline disconnect clutch is closed, the engine either provides no torque at the transmission input or acts as a drag (eg, crankshaft speed <DISG speed, then the driveline disconnect clutch output torque is negative). If the driver depresses the accelerator pedal (eg, the accelerator pedal is depressed) and the DISG does not have sufficient torque capacity at the DISG speed present, then the desired torque may not be delivered until the driveline disconnect clutch is closed and the engine is providing positive torque can.

Accordingly, in some conditions, it may be desirable to use the driveline disconnect clutch to increase engine speed to the DISG speed to more quickly close the driveline disconnect clutch and provide positive engine torque at the DISG output. The difficulty in closing the driveline disconnect clutch while the engine is accelerating to DISG speed is that the driveline disconnect clutch output torque is a function of sign (crankshaft speed - DISG speed). If the DISG is used to accelerate the crankshaft and dual mass flywheel inertia, then the difference between engine combustion torque and DISG torque applied to achieve a given acceleration level appears at the DISG output as negative torque then the sign suddenly changes to positive torque when the speed of the crankshaft (or dual mass flywheel output) exceeds the DISG speed.

A driveline disconnect clutch output torque change may produce a torque spike at the DISG input that may be transmitted to the transmission input and / or to the wheels. Therefore, the DISG may be operated as a torque disturbance suppression device to reduce the engine restart torque increase. The torque at the DISG output is the sum of the DISG output torque and the driveline disconnect clutch output torque. The control of the DISG may be based on the detection of the torque disturbance at one or more of the driveline disconnect clutch output, the DISG output, the torque converter output, and / or the transmission output. The torque sensor may allow the DISG to directly suppress the torque disturbance. Such a torque detection may be provided by a non-contact gear shaft torque sensor.

When such a sensor is applied to the shaft between the driveline disconnect clutch and the DISG rotor, the sensed torque may be input to the DISG controller to generate an opposing torque. to override the engine restart driveline disconnect clutch output torque peak. Alternatively, the torque sensor may be disposed on the shaft between the DISG rotor and the torque converter (or impeller). In one such example, the inertia and acceleration of the DISG rotor are included and are taken into account in the interference suppression torque calculation. A transmission input or transmission output shaft torque sensor may be further employed. When a transmission output shaft torque sensor is employed, the interference suppression torque term may include compensation for transmission inertias and, optionally, clutch states.

Regarding 4 FIG. 10 is a flowchart of an example method of operating a vehicle driveline using the methods of FIG 5 - 47 shown. The procedure of 4 and the following methods may be used as executable instructions in a nonvolatile memory of the type described in US Pat 1 - 3 shown control unit 12 be saved. Vertical marks such. B. T ₀ -T ₈ , in 10 are also shown indicating points of interest during the following depicted sequences.

at 402 determines the procedure 400 Operating conditions. The operating conditions may include, but are not limited to, torque request, engine speed, engine torque, DISG speed and DISG torque, vehicle speed, ambient temperature and pressure, and battery state of charge. The torque request can be from the accelerator pedal 130 and from the control unit 12 from 1 be derived. The procedure 400 go to 404 continue after the operating conditions are determined.

at 404 puts the procedure 400 the driveline operation and the operating parameters according to the methods of 5 - 8th one. In particular, the method provides 400 driveline operation in response to driving route conditions and / or driver behavior. The procedure 400 go to 406 after the driveline operation and operating conditions are set.

at 406 puts the procedure 400 the driveline or driveline operation for the vehicle mass, as in 9 and 10 described. In one example, the timing and conditions for engine stoppage may be adjusted in response to vehicle mass so that driveline wear and the number of driveline disconnect clutch state changes may be reduced. The procedure 400 go to 408 continue after the driveline operation is set for the vehicle mass.

at 408 assess the procedure 400 Whether an engine start is desired or not. Engine starting may be requested via a driver key input or driver pushbutton input having a single function for requesting engine start and / or stop. Alternatively, an engine restart may be automatically performed by the control unit 12 based on operating conditions that do not include driver actuation of a device having a single engine stop or start requesting function. The control unit 12 For example, engine start may be requested in response to a driver releasing the vehicle brake pedal or in response to a battery state of charge. Thus, a request to restart the engine may be initiated via inputs having functions other than just requesting engine startup. If the procedure 400 judges that an engine restart is requested, the procedure goes 400 to 410 further. Otherwise, the procedure goes 400 to 418 further.

at 410 chooses the procedure 400 a device for starting an engine, as in 11 and 12 described. In one example, the engine may be started via a starter having a lower power output than the DISG. In another example, the engine may be started via the DISG while the lower power output starter remains disabled. The procedure 400 go to 412 after the engine starting means is selected.

at 412 puts the procedure 400 the fuel injection timing of one or more direct fuel injection nozzles that supply fuel to an engine, as in 13 and 14 described. The fuel injection timing is adjusted to provide a single or multiple fuel injections during a single cylinder cycle. By setting the fuel injection timing, the engine speed profile during the engine start-up (z. B. engine acceleration (from the cranking speed z. B. 250 min ^-1)) to the desired engine idle speed. The procedure 400 go to 414 after the fuel injection timing is set.

at 414 assess the procedure 400 Whether the engine start is gear shift related or not. The procedure 400 For example, it judges whether it is desired to change the engine based on shifting from one gear to another to start another gear. If the procedure 400 judges that it is desired to start the engine based on transmission shifts or predicted transmission shifting, the method goes 400 to 416 further. Otherwise, the procedure goes 400 to 418 further.

at 416 starts the procedure 400 the engine during transmission shifting, as in 15 - 18 described. In one example, the engine may be started before the speed clutches are opened or closed during a shift. The procedure 400 goes after starting the engine 418 further.

at 418 creates the procedure 400 a compensation of the dual mass flywheel (DMF). Furthermore, the method can 400 Provide a driveline disconnect clutch compensation. DMF compensation can dampen torque transfer across the DMF by controlling DISG torque and / or DISG speed and driveline disconnect torque. The DMF compensation is provided as in 19 - 22 described. The procedure 400 go to 420 continue as soon as the DMF compensation is initiated.

at 420 assess the procedure 400 whether it is desired to stop the rotation of the engine or not. The procedure 400 may judge that it is desirable to stop the rotation of the engine during low torque request conditions and / or other conditions. The procedure 400 go to 422 further, if it is judged desirable to stop the rotation of the engine. The procedure 400 go to 420 when it is judged not to stop the rotation of the engine.

at 422 puts the procedure 400 the engine stop profile. In one example, during engine deceleration, engine speed is set to zero speed such that engine position at zero engine speed is desired to restart the engine. The engine stop profile can be adjusted as in 23 - 26 described. The procedure 400 go to 424 after the engine stopping profile has been selected and / or adjusted.

at 424 puts the procedure 400 Drive train operation for rollback conditions. In one example, the powertrain is selectively adjusted in response to the vehicle road slope. The procedure 400 continues to the end after the drivetrain is adjusted in response to the vehicle road incline.

at 430 assess the procedure 400 whether vehicle brakes on the drivetrain is desired or not. The procedure 400 may judge that it is desirable to provide vehicle brakes via the driveline when the vehicle is going down a hill or during other conditions. If the procedure 400 judged that it is desirable to brake the vehicle via the driveline, the procedure goes 400 to 432 further. Otherwise, the procedure goes 400 to 434 further.

at 432 puts the procedure 400 DISG and engine operation to provide a desired level of vehicle braking via the driveline, as in FIG 29A - 36 described. In one example, vehicle braking is provided via the DISG when the battery state of charge (SOC) is less than a threshold level. The procedure 400 go to 434 continue after vehicle braking is provided over the driveline.

at 434 assess the procedure 400 Whether to enter or leave a sailing mode or not. In one example, the sailing mode may be described as when the engine is operating at a sail idling speed (eg, combustion of air and fuel) while the driveline disconnect clutch is open. The sail idling speed is lower than the engine idle speed when the engine is burning an air / fuel mixture and the driveline disconnect clutch is closed. Additionally, the engine may be operated in an Atkinson cycle mode while in sail mode. Further, in some examples, the spark timing may be advanced to near or to a minimum spark timing for a maximum engine torque (MBT). In one example, the sailing mode may be entered if the DISG torque is within a predetermined range of a threshold DISG torque. The procedure 400 go to 436 further, if it is judged desirable to enter or leave the sailing mode. Otherwise, the procedure goes 400 to 438 further.

at 436 can the procedure 400 operate the engine and driveline in a sailing mode in which the engine operates under an efficient operating condition and in which the driveline disconnect clutch is open while the DISG provides torque to the vehicle driveline, as in US Pat 38 described. Alternatively, the method 400 leave the sailing mode, as in 39 described. The procedure 400 go to 438 continue after entering or exiting sail mode.

at 438 assess the procedure 400 whether the transfer function of the driveline disconnect clutch should be set or not. In one example, the method assesses 400 whether the transfer function of the driveline disconnect clutch during selected conditions such. B. while engine idle or engine stop conditions to be adjusted or not. If the procedure 400 judges that it is desirable to adjust the transfer function of the driveline disconnect clutch, the procedure goes 400 to 444 further. Otherwise, the procedure goes 400 to 440 further.

at 444 puts the procedure 400 the transfer function of the driveline disconnect clutch or adapts it as in 42 - 45 described. In one example, the driveline disconnect clutch transfer function describes torque train transfer of the driveline disconnect clutch based on input torque to the driveline disconnect clutch and pressure delivered to the driveline (eg, the hydraulic oil pressure delivered to the driveline disconnect clutch or the duty cycle of an electrical signal provided to the driveline disconnect clutch). The procedure 400 continues to the end after the driveline disconnect clutch transfer function is adjusted or adjusted.

at 440 operates the procedure 400 the engine and the DISG to provide a desired torque to the input of the transmission. In one example, the engine and the DISG are operated in response to the driveline torque request provided by a driver and / or the controller. For example, if 35 Nm of driveline torque is requested on the torque converter impeller, the DISG can supply 10 Nm to the driveline while the engine delivers the remaining 25 Nm to the driveline. Alternatively, the DISG or the engine can deliver the full 35 Nm to the driveline. The operating conditions of the engine and / or the DISG may also be considered to determine the amounts of torque output by the engine and the DISG. The procedure 400 go to 442 after the engine and DISG operating modes, speeds, and torques are output.

at 442 puts the procedure 400 the engine and DISG torque to provide a desired torque on the torque converter impeller. In one example, the torque on the torque converter impeller is estimated via a torque sensor. In other examples, the torque converter operating condition is a basis for estimating the torque at the torque converter impeller. The torque converter impeller torque estimation is as in FIG 21 described. The estimated gear pump torque is subtracted from a desired gear pump torque to provide a torque converter impeller torque error. The engine torque and / or the DISG torque are adjusted in response to the torque converter impeller torque error to reduce the torque converter impeller torque error toward zero. The procedure 400 continues to the end after the driveline torque is adjusted.

Regarding 5 FIG. 12 is a schematic diagram of example information that may be encountered while traveling from one location to another location. In the 5 shown sources of information stand for in 6 - 8th shown methods available. Furthermore, the in 6 shown sources of information and devices for in 1 - 3 shown systems available.

In this example, the vehicle can 290 the route number one 501 or route number two 502 drive to a first or a second destination. The vehicle 290 Can a solar charging system 504 for charging the energy storage device 275 , in the 2 shown. The solar charging system may include solar panels and other associated devices. In addition, the vehicle can 290 an inductive charging system 514 for charging the energy storage device 275 , in the 2 shown. The inductive charging system 514 can receive charge from a power source outside the vehicle while the vehicle is running. The vehicle 290 also includes a receiver 503 for receiving signals from outside or inside the vehicle 290 come.

The number one vehicle route includes a plurality of information sources, objects, and elements that may be the basis for selectively operating certain powertrain components. The vehicle 290 For example, information from a Global Positioning System (GPS) may be from a satellite 505 during a course of a journey. The GPS system can provide information to the processor 12 , as in 1 allow to determine road slopes and distances along route number one. The processor 12 may also contain information regarding vehicle stop, which is based on signs or signals 506 are stored during a course of a trip, so that when the vehicle 290 the route number one is traveling, the information is again available to determine when the vehicle is stopping, starting, accelerating, slowing down or traveling at a substantially constant speed (eg ± 5 mph).

The vehicle 290 can also estimate a lot of charge through the solar system 504 over the sun 507 while driving the route number one to the energy storage device 275 is delivered. For example, if the vehicle begins to drive route number one at 1:00 PM per minute to generate 1 watt / minute and is expected to take one hour to drive route number one, it can be estimated that there will be 60 watts during the course the route of route number one are generated. Further, the estimated power generated during the course of the trip may be set based on the time of day and the predicted weather. For example, an amount of electrical power generated at a specific time of day may be extrapolated to an amount of power generated later that day based on empirically determined solar tables and the time of day.

The vehicle 290 can also road conditions 508 to record in memory and save or from external sources such. B. GPS received. road conditions 508 may include road slope information, road surface information, and speed limits. The vehicle 290 can also be the ambient temperature of the temperature sensor 509 receive or measure. The temperature sensor 509 can in the vehicle 290 be integrated or he can get out of the vehicle 290 are located.

Finally, the vehicle can 290 on the route number one electrical power at the power source 510 receive. The power source 510 can be a residential or commercial power source, the power to the vehicle 290 from an electrical network at the destination one. The vehicle 290 may include stored information including a stored database and / or information stored from previous trips to destination one indicating that the vehicle 290 can be reloaded at the destination one. Such information is used to determine how electrical charge is in the vehicle 290 stored, is used during the course of a trip, useful.

In another example, the vehicle may 290 Drive via route number two to destination two. The vehicle 290 may be programmed to recognize that it is traveling to the destination two. Along the route number two can the vehicle 290 Weather, road condition, ambient temperature and GPS data from the infrastructure 515 receive. The infrastructure may include radio masts and highway / road radios. The vehicle 290 can also road conditions of handsets 513 such as As telephones, computers, tablet devices and / or personal organizers received. In some situations, the vehicle may 290 Road conditions and destination information (eg availability of electric charging stations) from other vehicles 511 that has information about a sender 512 deliver, receive.

Thus, a vehicle may receive information at the beginning of a journey and throughout the journey, which may be a basis for controlling driveline operation. In the 5 For example, the described sources of information may be the basis for operating the driveline disconnect clutch 236 , the DISG 240 and the engine 10 , in the 2 are shown.

Regarding 6 FIG. 12 is a flowchart of a method of operating a hybrid powertrain in response to information encountered while traveling from one location to another location. The procedure of 6 can run in non-volatile memory as executable commands in the system of 1 - 3 be saved.

at 602 determines the procedure 600 Vehicle operating conditions. Vehicle operating conditions may include, but are not limited to, engine speed, vehicle speed, ambient temperature, driver demand torque (eg, torque requested by a driver via input, and may be referred to as desired driveline torque in some examples) and energy storage device SOC limited to it. Further, the operating conditions may include selecting a route to a destination based on a driver input or by adapting a current travel route to travel routes taken during previous trips. The procedure 600 go to 604 after the vehicle operating conditions are determined.

at 604 records the procedure 600 Traveling route information. The procedure 600 can route information such. Road gradient, traffic lights, other vehicle speeds, traffic support locations, electrical recharge station locations, ambient temperature, and related traffic information from a variety of sources. The sources of information may include, but are not limited to, an internal memory of a control unit in the vehicle, personal hand-held devices (eg, personal organizers, tablets, computers, telephones), satellites, infrastructure, other vehicles, and traffic communication devices. The driving route of a vehicle may in one example be stored in the control unit memory Driving routes are compared. When the current travel route of the vehicle corresponds to a travel route stored in the control unit memory, the control unit selects the destination and the driving conditions (eg, traffic lights, road inclination, superchargers, etc.) from the travel route stored in the memory without driver input. The procedure 600 go to 606 continue after route information is captured.

at 606 prioritizes the procedure 600 the use of stored electrical energy based on opportunities to charge the electrical energy storage device along a selected travel route. 7 shows a way to prioritize the use of stored electrical energy. Prioritizing the use of stored electrical energy may include only the use of electrical energy during selected vehicle accelerations so that hydrocarbon fuel use may be reduced as compared to simply basing the use of electrical energy based on a desired torque request. Further, prioritizing the use of stored electrical energy may include using substantially all of the available stored charge (eg, reducing the energy storage device charge to a threshold amount of charge) in the electrical energy storage device when the vehicle is within a predetermined distance of a A track for external charging of the energy storage device is located, or in states in which the energy storage device can be charged via kinetic energy (eg a downhill). The procedure 600 go to 608 after the use of stored electrical energy is prioritized. In this way, the process plans 600 the use of stored electrical energy before the vehicle reaches driving conditions that facilitate the use of the stored electrical energy.

at 608 prioritizes the procedure 600 charging the electrical energy storage device via an engine based on a driving route. The procedure 600 For example, it may operate an engine to drive a vehicle when an energy storage device SOC is low. The procedure 600 may further operate the engine without charging the energy storage device when the method 600 determines that the energy storage device can be charged a short time later using the kinetic energy of the vehicle during vehicle deceleration. 8th shows a way to prioritize the charging of the electrical energy storage device. The procedure 600 go to 610 continue after the charging of the electrical energy storage device has been prioritized. In this way, the process plans 600 charging the electrical energy storage device before the vehicle reaches travel route conditions facilitating charging of the electrical energy storage device.

at 610 prioritizes the procedure 600 entry into the power train mode on the basis of the driving route of the vehicle. In one example, the procedure calls 600 Information from 702 of the procedure 700 to determine when to expect the vehicle to stop for less than a threshold amount of time. Furthermore, the method can 600 Receive information regarding when the vehicle is expected to accelerate above a threshold rate after the vehicle stops for less than the threshold amount of time. The procedure 600 plans to enter the sailing mode (eg, idle engine, driveline disconnect clutch open, and DISG that provides requested torque to the vehicle driveline) based on locations in the driving route that are expected to travel the vehicle for less than a threshold amount stops at time and is expected to accelerate the vehicle from vehicle stop at a rate greater than a threshold rate. The procedure 600 go to 612 continue after the entry into sailing mode is planned. In this way, the process plans 600 entering the sailing mode before the vehicle reaches driving conditions that facilitate sailing mode.

at 612 operates the procedure 600 the driveline disconnect clutch, the DISG and the engine based on the planned and prioritized use of electrical energy stored in the energy storage device, the prioritized charging of the electrical energy storage device via the engine and entry into the sailing mode. In other words, the procedure 600 may open and close the driveline disconnect clutch, operate the DISG, and operate the engine based on expected vehicle and road conditions along a driving route. If the procedure 600 plans to enter the sailing mode, for example, at a special stop during a route, opens the process 600 the driveline disconnect clutch and enters the sail mode when the vehicle stops at the specific location. Further, the method opens 600 the driveline disconnect clutch when it is planned that the DISG provides torque to accelerate the vehicle without assistance from the engine in response to the prioritization of the use of electrical energy stored in the electrical energy storage device. Still further, the procedure opens 600 the driveline disconnect clutch in response to the vehicle projecting within a threshold distance the arrival at an electrical charging station, so that energy from the electrical storage device can be used to power the vehicle rather than the engine and hydrocarbons. In addition, the process can 600 open the driveline disconnect clutch in response to being on a downhill slope within a threshold distance before arrival. The procedure 600 go to 614 after the driveline disconnect clutch operation is scheduled and executed based on vehicle and track conditions.

at 614 assess the procedure 600 whether there has been a significant change in the route and / or vehicle conditions or not. A significant change in the route or vehicle conditions may be the presence of an unexpected condition (eg, a prolonged vehicle stop or an unexpected loss of battery charge) or the absence of an expected condition (eg, no vehicle stop if a vehicle stop is expected) , If the procedure 600 judged that there was a change in the driving route or vehicle conditions, the answer is Yes and the method 600 returns 602 so that the prioritization of stored electrical energy, energy device charging, and sail mode entry can be redetermined. Otherwise, the answer is no and the procedure 600 go to 616 further.

at 616 assess the procedure 600 whether the vehicle is at its final destination for the ride or not. In one example, the method compares 600 the current location of the vehicle with a programmed destination. In another example, the method compares 600 the current location of the vehicle with an expected destination. If the procedure 600 judges that the vehicle is at its destination, the procedure goes 600 continue to the end. Otherwise, the procedure returns 600 to 614 back.

In this way, the operation of a hybrid powertrain can be adjusted according to a driving route and conditions along the driving route. Adjustments to the hybrid powertrain may include, but are not limited to, opening and closing a driveline disconnect clutch, charging an energy storage device via the engine, entering the sailing mode, and entering and exiting to or from other driveline operating modes.

Regarding 7 FIG. 3 is a flowchart of a method of prioritizing the use of stored electrical energy in a hybrid vehicle. The method is based on the use of stored electrical energy on opportunities to charge an electrical energy storage device via a driving route. The procedure of 7 can be stored in a non-volatile memory as executable commands in the system of 1 - 3 be saved.

at 702 determines the procedure 700 a number of vehicle stops and their locations on a driving route and estimates the regenerative energy delivered to the electrical energy storage device during vehicle stop and during other occasions (eg, vehicle deceleration and during a downhill ride). The procedure 700 can also estimate an expected amount of battery charge via a solar charging system. Furthermore, the method determines 700 a number of vehicle accelerations from the stop and an estimate of the electrical energy to accelerate from each vehicle stop. In addition, the process can 700 Store information about vehicle stops that are less than a threshold time period.

In one example, the number of vehicle stops and their locations are estimated based on a number of traffic lights and / or signs along the route, as shown in FIG 5 determined sources of information. In particular, in one example, the number of vehicle stops is calculated from the number of traffic lights and / or signs along a route, multiplied by a value representing a reasonable percentage (eg, 60%) of the traffic lights at which the vehicle actually stops , certainly. The number of accelerations from the stop is equal to the estimated number of vehicle stops. The amount of energy regenerated during each vehicle stop may be calculated based on the vehicle speed before stop, road grade, and vehicle mass (eg, using E = 1/2 mv ² , where E is the energy , m is the vehicle mass and v is the vehicle speed, or alternatively F = m · a + m · g · sin (Θ) over the time interval, where m is the vehicle mass, a is the vehicle acceleration, g is the gravitational acceleration, and θ is the vehicle acceleration Street angle is that can be converted into a slope). Also, the amount of energy for accelerating the vehicle may be calculated based on the speed limit, road grade, and vehicle mass (eg, using F = m * a + m * g * sin (Θ) over the time interval, or E = 1/2 mv ² ) and then converted into electrical charge. Further, energy received from solar or inductive devices along the route may be added to the total amount of charge available while driving the route. The number of traffic lights, their locations and the road gradient information may be in excess of the ones in 5 shown Information sources are determined. The procedure 700 go to 704 After the number of vehicle stops, the vehicle accelerations, the regenerated energy and the energy used to accelerate the vehicle at each vehicle stop port are determined.

at 704 assess the procedure 700 Whether the energy storage device has energy to accelerate the vehicle to the speed limit after each 702 can deliver certain vehicle stop or not. In one example, the energy stored in the energy storage device plus the estimated amount of regenerative energy available along the travel route are added together. Driveline losses are subtracted from the sum of stored energy and regenerative energy, and the result is compared to the estimated amount of energy to accelerate the vehicle from all vehicle stops. If the amount of energy for accelerating the vehicle from all vehicle stops is greater than the sum of the stored energy and the regenerative energy, it may be determined that engine assistance may be required along the travel route and that the energy storage device may not have stored enough power to complete the journey over the route. If the energy storage device can not have enough power to accelerate the vehicle out of all stops along the selected route, the answer is no and the method 700 go to 706 further. Otherwise, the answer is yes and the procedure 700 go to 708 further.

at 706 chooses the procedure 700 which accelerations are performed from the stop using energy from the energy storage device. In other words, the procedure 700 decides during which vehicle accelerations the DISG provides torque to the driveline. In one example, the choice of vehicle accelerations that operate the DISG is based on which accelerations from the stop, when combined, require an amount of energy that most closely matches the amount of energy available from the energy storage device stands. For example, at the beginning of a journey, when an energy storage device X stores Coulomb charge and the first twenty-three vehicle accelerations X are expected to use Coulomb energy, the first twenty-three vehicle accelerations are provided across the DISG and the energy storage device. It should be noted, however, that the selected vehicle accelerations need not be consecutive in order. Rather, individual vehicle accelerations operating across the DISG and the energy storage device may be selected from any acceleration during the planned vehicle route.

In another example, the accelerations from the vehicle stop, where the DISG is operated with charge from the energy storage device, are based on when energy from the regeneration is available to charge the energy storage device and an expected amount of energy at the time of the Vehicle stops is stored. For example, if only a small amount of regenerative energy is expected during a vehicle deceleration and the energy storage device charge is expected to be less than a threshold at a vehicle stop, the DISG is not scheduled to accelerate the vehicle from that particular vehicle stop. The procedure 700 go to 716 after vehicle accelerations from vehicle stop, where the DISG is operated with charge from the energy storage device, are determined.

at 708 determines the procedure 700 a number and locations of accelerations of the traveling vehicle not from the vehicle stop. The procedure 700 Also, estimates an amount of energy to accelerate the vehicle during each acceleration of the moving vehicle. The locations and the number of accelerations of the moving vehicle can be determined from where changes in the speed limit over the course of the route occur. Consequently, a number of accelerations of the traveling vehicle can be determined from any increase in the speed limit set up on the driving route. The change in vehicle route speed may be stored in a map database and retrieved from the memory. Further, the vehicle route may be determined based on the shortest distance or the shortest time between the current location of the vehicle and a requested destination.

The procedure 700 Also determines the energy for accelerating the vehicle at each of the vehicle acceleration locations. The amount of energy for accelerating the vehicle may be calculated based on the speed limit, road grade, and vehicle mass (eg, using F = m * a + m * g * sin (Θ) over the time interval or E = 1/2 mv ² ). The procedure 700 go to 710 After the number of accelerations during driving, the locations of the accelerations of the moving vehicle and estimated for accelerating the vehicle at each acceleration point of the moving vehicle energy are determined.

at 710 assess the procedure 700 Whether the energy storage device can supply the energy for accelerating the vehicle to the speed limit or not after each acceleration of the traveling vehicle at 708 is determined. In one example, any remainder of the amount of energy stored in the energy storage device plus the amount of regenerative energy estimated as being available along the travel route minus 702 certain energy for accelerating the vehicle at each stop is compared with an amount of energy for accelerating the vehicle at all acceleration locations of the traveling vehicle. When the amount of energy for accelerating the moving vehicle at each location is greater than the rest of 702 , it may be noted that engine assist along the travel route may be required and that the energy storage device may not have stored sufficient power to provide electrical power over the route. If the energy storage device does not have enough power to accelerate the vehicle from all accelerations of the traveling vehicle along the selected route, the answer is No and the method 700 go to 714 further. Otherwise, the answer is yes and the procedure 700 go to 712 further.

at 712 chooses the procedure 700 from where, during the travel route, the remaining energy stored in the energy storage device and generated during regeneration (eg, during vehicle deceleration) may be consumed. For example, if the energy storage device X Coulomb has residual charge above a threshold amount of charge and a source of charge is available at the vehicle target, the method determines 700 at which point along the route the remaining charge is consumed. In one example, the consumption of the remaining charge stored in the energy storage device and not used to accelerate the vehicle is consumed starting at a location based on the destination. For example, if the vehicle Z Coulomb is expected to have excess charge and the vehicle uses 1 / Z coulombs per mile, the driveline disconnect clutch is opened and the DISG begins discharging the Z Coulomb Z miles away from the target and the engine is stopped. In this way the procedure decreases 700 the energy stored in the energy storage device in a manner that can reduce hydrocarbon fuel consumption as the consumed stored electrical energy is increased by consuming the energy storage charge to a threshold charge level (eg, a minimum battery charge level). Further, since the vehicle can be recharged via the network at the destination, the energy storage device can be recharged with power from a more efficient source than the engine.

If, on the other hand, the process 700 determines that there is no charging source at the target, the driveline disconnect clutch is closed and the energy can remain stored in the electrical energy storage device. The procedure 700 go to 716 after determining where excess charge that is not consumed during vehicle acceleration is consumed.

at 714 chooses the procedure 700 from which accelerations of the moving vehicle are performed with energy from the energy storage device. In other words, the procedure 700 decides during which accelerations of the traveling vehicle (eg, vehicle accelerations not off the stop) the DISG provides torque to the driveline. In one example, the choice of accelerations of the traveling vehicle on which the DISG is operated is based on which accelerations of the traveling vehicle in combination require an amount of energy that most closely corresponds to the amount of energy remaining after vehicle accelerations the vehicle stop has been provided with energy for accelerating the vehicle. For example, at the beginning of a journey, if an energy storage device X stores Coulomb charge and there are twenty-three vehicle accelerations from the stop that are expected to use Y Coulomb energy (eg, Y is less than X), the first twenty-three vehicle accelerations will turn off the vehicle stop via the DISG and the energy storage device provided. If it is expected that Z Coulombs are left after every acceleration of the vehicle at each stop and the energy consumption sum of the energy of the acceleration of the traveling vehicle is greater than Z Coulomb, for the first accelerations of the traveling vehicle charging up to Z Coulombs, provided the Z Coulomb charge. It should be noted, however, that the selected accelerations of the moving vehicle in which the excess charge is delivered need not be consecutive in order. The procedure 700 go to 716 after the accelerations of the traveling vehicle receiving DISG support and charge from the energy storage device are selected.

at 716 plans the procedure 700 DISG support for the driveline to accelerate or move the vehicle based on the particular locations of accelerations and stationary energy usage. The DISG Assistance can be provided when the driveline disconnect clutch is in an open state or during a closed state. Further, the DISG may deliver all or part of the torque to propel the vehicle.

In this way, it is possible to plan and prioritize the use of stored electrical energy. In this example, vehicle accelerations of zero speed have a higher priority than accelerations of the traveling vehicle or the use of stored electric power during steady-state driving conditions. Such operation may allow the engine to operate with more efficient operating conditions, such as, for example, engine loads. B. stationary speed and load conditions works.

Regarding 8th 1 is a flowchart of a method for scheduling and prioritizing the charging of an electrical energy storage device via an engine based on a driving route. The procedure of 8th can be stored in a non-volatile memory as executable commands in the system of 1 - 3 be saved.

at 802 calls the procedure 800 Information from 702 and 708 from 7 to determine when it is expected that the electrical energy storage device requires charging. Especially if at 702 from 7 it is determined that the vehicle can not accelerate from any conditions at a speed of zero, the procedure can 800 determine that the electrical energy storage device must be recharged at a location of vehicle acceleration along the travel route at which the SOC is reduced to less than a threshold level. Likewise, the process can 800 estimate where along the travel route the SOC is reduced to less than a threshold level during acceleration during driving or during steady state driving conditions. The procedure 800 goes after determining when it is expected that the electrical energy storage device requires recharging 804 further.

at 804 assess the procedure 800 Whether or not the electric energy storage device has enough charge to drive the vehicle for the whole ride. In one example, the SOC is compared to an estimate of the energy for operating the vehicle over the entire journey on the basis of F = m * a + m * g * sin (Θ) over the time interval or E = 1/2 mv ² . If the procedure 800 is judged that the electric energy storage device has enough stored charge to operate the DISG over the entire travel route, the answer is Yes and the method 800 continue to the end. Otherwise, the answer is no and the procedure 800 go to 806 further.

at 806 determines the procedure 800 Sections and locations of the travel route where the charging of the energy storage device via the engine is most efficient and where the SOC is expected to be low. It can be at the 702 . 708 and 714 from 7 certain places, the SOC is expected to be low. The locations and portions of the travel route where charging of the energy storage device may be most efficient may be based on empirically determined engine speeds and loads where the engine consumes the least fuel for each mile driven. For example, when determined that the engine with the consumption of most fuel for each driven miles at 2200 min ^-1 is carried out between an engine load of 0.2 and 0.3, it can be determined that the energy storage device via the combustion engine at a vehicle speed should be recharged when the engine is 2200 min ^-1, and between 0.2 and 0.3 load when the DISC charges the energy storage device. In one example, the method chooses 800 Thus, locations and portions of the travel route for charging the energy storage device based on locations of roads at constant vehicle speeds (eg, a speed limit of 55 MPH) for extended durations (eg, 10 miles) that correspond to efficient engine operating conditions. In some examples, vehicle speeds are selected where engine efficiency is expected to be greater than a threshold efficiency. Engine efficiency at a particular vehicle speed may be determined empirically and stored in memory. The procedure 800 go to 808 After sections of the driving route, where the charging of the energy storage device via the engine is most efficient, are determined.

at 808 determines the procedure 800 Locations and portions of the travel route where the charge supplied by the engine to the energy storage device can be fully utilized. The procedure 800 For example, estimates the amount of energy that can be used to drive the vehicle from its current location where charging of the energy storage device via the engine is considered to the final destination. The energy storage device may be recharged at any location along the travel route where the engine efficiency is greater than a threshold efficiency and where the amount of energy for driving the vehicle from its current location to its destination is greater than a threshold amount of charge (e.g. . the Charge capacity of the energy storage device). The procedure 800 go to 810 after sections of the travel route where the charge supplied by the engine to the energy storage device can be fully utilized.

at 810 chooses the procedure 800 Locations and portions of the travel route where the engine can most efficiently deliver charge to the energy storage device and where the charge supplied by the engine to the energy storage device can be fully utilized during the travel route. For example, if it is determined that the energy storage device stores enough energy to power the vehicle for 10 miles and the vehicle is 20 miles away from the target and operates at an efficiency greater than a threshold efficiency, the location may be 20 miles from the destination Place to charge the energy storage device can be selected via the engine. The driveline disconnect clutch is closed when the engine boosts the electrical energy storage device via the engine. The procedure 800 proceeds to the end after locations for charging the electrical energy storage device via the engine are selected.

In this way, the charging of the energy storage device via the engine may be prioritized based on where the engine can operate efficiently during charging and on the basis of the vehicle location that is a distance away from the target that allows the use of any charge. which can be supplied via the engine to the energy storage device. Further, the prioritization may be the basis for determining locations of driveline mode changes.

Consequently, the methods and systems of 1 - 8th operating a hybrid vehicle, comprising: operating a driveline disconnect clutch in response to a vehicle target. In this way, the driveline operation can be improved. The method includes where operating the driveline disconnect clutch includes opening the driveline disconnect clutch in response to information that a supercharger is available at the vehicle target. The method further includes stopping an engine and reducing an amount of charge stored in an energy storage device in response to an estimate of the energy that the hybrid vehicle driveline uses to reach the vehicle destination. The method includes reducing the amount of charge via operating a driveline integrated starter / generator. The method includes where operating the driveline disconnect clutch includes closing the driveline disconnect clutch in response to information indicating that a recharge device is not available at the destination. The method further includes closing the driveline disconnect clutch and charging an energy storage device in response to a location of the vehicle target.

The methods and systems of 1 - 8th also provide operating a hybrid vehicle, comprising: receiving travel route information at a control unit; and selectively actuating a driveline disconnect clutch in response to the driving route information. The method includes where the driving route information includes whether or not a charging station is available at a destination, and selectively operating the driveline disconnect clutch opens the driveline disconnect clutch in response to an amount of energy that is expected to be consumed by the hybrid vehicle to reach the destination includes.

In some examples, the method includes where the driving route information includes an indication of a downhill slope and the driveline disconnect clutch is kept open in response to the indication of the downhill slope. The method includes storing the travel route information in the control unit from a previous trip via the travel route. The method further includes accessing the driving route information based on a current route of a vehicle and opening or closing the driveline disconnecting clutch in response to the availability of charging devices at a destination. The method also includes selectively operating the driveline disconnect clutch including opening and closing the driveline disconnect clutch in response to a number of expected vehicle stops during travel routes.

In one example, the method includes where the selective actuation of the driveline disconnect clutch includes opening and closing the driveline disconnect clutch in response to a number of accelerations of the traveling vehicle that do not include vehicle accelerations from the vehicle stop. The method includes where selectively operating the driveline disconnect clutch includes opening and closing the driveline disconnect clutch in response to a number of vehicle accelerations from the vehicle stop. Further, the method includes the driving route information including road gradient information, and further comprising storing charge in an electrical energy storage device in response to the driving route information.

The methods and systems of 1 - 8th additionally provide operation of a hybrid vehicle, comprising: evaluating the state of charge (SOC) of an electrical energy storage device; Receiving travel route information at a control unit; and scheduling the charging of the electrical energy storage device at a first location in response to the SOC and the driving route information prior to reaching the first location. The method also includes where the hybrid vehicle receives travel route information from a vehicle other than the hybrid vehicle. The method further includes operating a driveline disconnect clutch in response to the driving route information. The method further comprises updating the scheduling of the charging of the electrical energy storage device in response to a change in the driving conditions. The method further includes scheduling the discharge of the electrical energy storage device at a second location prior to reaching the second location.

Regarding 9 3, a flow chart of a method for an example sequence for operating a hybrid vehicle powertrain in response to a variable vehicle mass is shown. The procedure of 8th can be used as executable commands in a nonvolatile memory in the system of 1 - 3 be saved. Furthermore, the method of 9 in the 10 provide the sequence shown.

at 902 determines the procedure 900 Vehicle operating conditions. The vehicle operating conditions may include, but are not limited to, engine speed, vehicle speed, energy storage device SOC, engine load, engine torque request, and vehicle acceleration. The operating conditions may vary from those specified in 1 - 3 be described or derived sensors described. The procedure 900 go to 904 after the vehicle operating conditions are determined.

at 904 determines the procedure 900 the vehicle mass. In one example, the vehicle mass is based on the following equations:
When the vehicle acceleration is zero, Powertrain / driveline torque ≈ road load + pitch-based torque

Using: T_wh1 = R_rr * M_v * g * sin (θ ₁ ) + T_rl1
in which:
T_wh1 = wheel torque at inclination angle = θ1
T_wh2 = wheel torque at inclination angle = θ2
R_rr = rolling radius of the driven wheel
M_v = vehicle mass estimate
g = gravitational constant
θ ₁ = inclination angle
T_rl1 = road load torque on the driven wheel on the inclination 1
T_rl2 = road load torque on the driven wheel on the slope 2

Then the vehicle mass estimate is: M_V = [(T_wh1 - T_wh2) + (T_rl2 - T_rl1)] / [R_rr · g · (θ ₁ - θ _2)]

In some examples, the vehicle mass includes the mass of a vehicle and a trailer being towed by the vehicle. In other examples, the vehicle mass is the mass of only the vehicle without a trailer. In some examples, the vehicle mass may further include the mass of occupants in the vehicle and the vehicle load. The engine / driveline torque may be determined from empirically determined torque maps or functions indexed using engine speed and load. The engine torque may be estimated, for example, by indexing a map of engine output torque indexed by engine speed and load. The procedure 900 go to 906 continue after the vehicle mass is estimated.

at 906 puts the procedure 900 the energy storage device SOC threshold at which automatic engine stoppage is committed. In one example, the energy storage device SOC threshold is increased when the mass of the vehicle is increased such that the vehicle's engine stops during vehicle deceleration conditions when the energy storage device is more than a first threshold level. When the mass of the vehicle is reduced, the energy storage device SOC threshold is decreased so that the vehicle's engine stops during vehicle deceleration conditions when the energy storage device is at more than a second threshold level, wherein the second threshold level is less than the first threshold level. The energy storage device SOC threshold may be set in proportion to a change in vehicle mass or as a function of vehicle mass. 10 shows two SOC threshold levels based on different vehicle masses. The procedure 900 go to 908 after the energy storage device SOC threshold for engine stop is set.

at 908 assess the procedure 900 whether conditions for automatically stopping the Engine or not. In some examples, conditions for automatically stopping the engine include conditions indicative of a vehicle deceleration, a brake pedal, the absence of accelerator pedal descent, and an energy storage device SOC greater than a threshold level. If the procedure 900 judged that conditions for automatically stopping the engine are satisfied, the answer is Yes and the method 900 go to 910 further. Otherwise, the answer is no and the procedure 900 go to 912 further.

at 910 stops the procedure 900 the engine automatically. The engine may be automatically stopped by stopping the fuel and / or the spark for the engine without the driver requesting engine stop via a device having a single function to stop and / or start the engine. The procedure 900 go to 912 continue after the engine is stopped.

at 912 assess the procedure 900 whether the engine was stopped automatically or not. In one example, a bit is set in the controller memory when the engine is automatically stopped. If the procedure 900 judged that the engine was stopped automatically, the answer is yes and the procedure 900 go to 914 further. Otherwise, the answer is no and the procedure 900 ends.

at 914 assess the procedure 900 whether the vehicle mass is less than a threshold mass or not. In one example, the threshold mass is the vehicle mass of an unloaded vehicle plus mass adjustments for one or more persons and a fixed amount of cargo. If the procedure 900 judged that the vehicle mass is less than a threshold mass, the answer is yes and the method 900 go to 916 further. Otherwise, the answer is no and the procedure 900 go to 922 further.

at 916 assess the procedure 900 Whether a friction brake application force is less than a threshold or not. Alternatively, the procedure assesses 900 at 916 whether a brake pedal is applied or not. If the friction brake application force is less than a threshold or if the brake pedal is not applied, the answer is Yes and the method 900 go to 918 further. Otherwise, the answer is no and the procedure 900 continue to the end.

at 918 leaves the procedure 900 The engine is in a stopped state and provides a threshold amount of creep torque (eg, a torque that moves the vehicle at a predetermined slow speed rate (2 miles / h) on a flat slope) to the vehicle wheels via the DISG. The procedure 900 go to 920 continues after the creep torque is output through the DISG.

at 920 provides the procedure 900 a base amount of torque converter impeller torque in response to a driver request torque. The basic amount of torque converter impeller torque does not take into account any change in vehicle mass. In one example, the base amount of torque converter impeller torque is based on driver input to an accelerator pedal (eg, driver demand torque), and an amount of accelerator pedal deflection is converted to torque converter impeller torque. In other examples, wheel torque, engine brake torque, and / or driveline related torque may take the location of torque converter impeller torque. The torque converter impeller torque is converted to a desired DISG flow and the flow is provided to the DISG to provide the torque converter impeller torque.

at 922 assess the procedure 900 Whether the friction brake application force is less than a threshold or not. Alternatively, the procedure assesses 900 at 922 whether a brake pedal is applied or not. If the friction brake application force is less than a threshold or if the brake pedal is not applied, the answer is Yes and the method 900 go to 924 further. Otherwise, the answer is no and the procedure 900 continue to the end.

at 924 When the engine is restarted, the driveline disconnect clutch is closed and at least a portion of the vehicle creep torque is provided by the engine. In some examples, the vehicle creep torque may be provided via the engine and the DISG. In other examples, vehicle creep torque is provided only via the engine. The procedure 900 go to 926 after the engine is started and at least part of the vehicle creep torque is provided by the engine.

at 926 provides the procedure 900 an amount of torque converter impeller torque adjusted to vehicle mass in response to a driver request torque. The procedure 900 For example, it provides a base amount of torque converter impeller torque plus an additional amount of torque based on the increase in vehicle mass. In one example, the additional amount will be Torque determined empirically and stored in a table or function in the control unit memory, which is indexed by the vehicle mass that exceeds the base vehicle mass. The torque converter impeller torque may be provided only via the engine or via the engine and the DISG. In one example, the desired torque converter impeller torque is provided by opening the engine throttle and supplying fuel to the engine in response to the desired torque converter impeller torque. In other examples, the desired torque converter impeller torque is provided via the supply of the DISG with an amount of power and the engine having fuel and a throttle opening amount. The procedure 900 proceeds to the end after the desired torque converter impeller torque is provided.

In this manner, the engine and driveline disconnect operations may be adjusted in response to a change in vehicle mass. Further, the conditions for stopping the engine based on the SOC may also be set based on the vehicle mass.

Regarding 10 an example sequence for operating a hybrid vehicle powertrain in response to a variable vehicle mass is shown. The sequence of 10 can about that in 10 be performed method shown in the in 1 - 3 described system is executed.

The first diagram from the top of 10 is a graph of vehicle speed as a function of time. The Y-axis represents the vehicle speed and the vehicle speed increases in the direction of the Y-axis arrow. The X-axis represents the time and the time increases in the direction of the X-axis arrow.

The second diagram from the top of 10 FIG. 13 is a graph of the engine operating condition as a function of time. The Y axis represents the engine operating condition. The engine is on and operating the combustion of an air / fuel mixture when the curve is at a higher level. The engine is off and does not burn when the curve is at a lower level. The X-axis represents the time and the time increases in the direction of the X-axis arrow.

The third diagram from the top of 10 Figure 12 is a graph of the vehicle brake application state as a function of time. The Y-axis represents the vehicle brake state. The vehicle brake pedal is applied when the curve is at a higher level. The vehicle brake pedal is not applied when the curve is at a lower level. The X-axis represents the time and the time increases in the direction of the X-axis arrow.

The fourth diagram from the top of 10 FIG. 12 is a graph of desired torque converter impeller torque versus time. FIG. The Y axis represents the desired torque converter impeller torque and the desired torque converter impeller torque increases in the direction of the Y axis arrow. The X-axis represents the time and the time increases in the direction of the X-axis arrow.

The fifth diagram from the top of 10 Figure 12 is a diagram of the energy storage device charge state (SOC) as a function of time. The Y axis represents the energy storage device SOC, and the energy storage device SOC increases in the direction of the Y axis arrow. The X-axis represents the time and the time increases in the direction of the X-axis arrow. The horizontal mark 1002 represents a minimum energy storage device SOC level at which the engine may be stopped and the driveline disconnect clutch may be opened as vehicle mass increases, for example, via an increase in vehicle payload. The horizontal mark 1004 represents a minimum energy storage device SOC level at which the engine may be stopped and the driveline disconnect clutch may be opened when the vehicle mass is that of the unloaded base vehicle. Thus, at lower SOC levels, the engine may be stopped and the driveline disconnect clutch opened when the vehicle is at its base ground. On the other hand, if the vehicle mass increases, the engine may be stopped at a higher SOC level and the driveline disconnect clutch opened so that the engine will continue to operate unless the energy storage device is on a higher level SOC.

The sixth diagram from the top of 10 is a graph of vehicle mass as a function of time. The Y axis represents the vehicle mass and the vehicle mass increases in the direction of the Y axis arrow. The X-axis represents the time and the time increases in the direction of the X-axis arrow.

The seventh diagram from the top of 10 Figure 13 is a diagram of the driveline disconnect clutch condition as a function of time. The driveline disconnect clutch is in an open state when the cam is on a lower level. The driveline disconnect clutch is in a closed state when the curve is at a higher level. The X-axis represents the time and the time increases in the direction of the X-axis arrow.

At time T ₀ , the vehicle speed is zero, the engine is stopped, the brake pedal is applied, the energy storage device SOC is relatively high, the driveline disconnect clutch is open, and the vehicle mass is at a lower level. In this example, the engine was automatically stopped in response to the vehicle speed being zero and the brake pedal being applied.

At time T ₁ , the driver releases the brake pedal and the vehicle speed gradually increases as the DISG (not shown) applies torque to the vehicle driveline in response to the driver releasing the brake pedal. The engine remains in an off state and the driveline disconnect clutch remains open. The desired torque converter impeller torque increases in response to the driver releasing the brake pedal and then increasing driver demand torque. The driver demand torque may be engine brake torque, torque converter impeller torque, wheel torque, or other driveline torque. The vehicle mass remains at a lower level and the energy storage device SOC begins to decrease as the DISG alone powers the vehicle.

At time T ₂ , in response to a driver torque request (not shown), the desired torque converter impeller torque has increased to a level at which the engine is automatically started and the driveline disconnect clutch is closed. The engine may be automatically started without direct driver input into an apparatus having a single purpose for starting and / or stopping the engine (eg, an ignition switch) when the driver demand torque exceeds a threshold torque level. The vehicle speed. continues to increase in response to increasing torque converter impeller torque. The vehicle mass remains at a lower level and the energy storage device SOC is further reduced as the vehicle accelerates. The vehicle brake pedal remains in an inactive position.

At time T ₃ , the vehicle begins to decelerate in response to a decreased driver torque request. The vehicle mass is at a lower level and the energy storage device SOC is greater than the threshold level 1004 such that in response to the vehicle entering a deceleration mode when the driver demand torque is reduced, the driveline disconnect clutch is opened and the engine is stopped. The desired torque converter impeller torque is reduced in response to the reduced driver request torque. The vehicle brake pedal state remains off and the energy storage device begins to charge via the DISG, which converts vehicle inertia into electrical energy.

Between time T ₃ and time T ₄ , the vehicle stops and the vehicle brake is applied by the driver. The energy storage device SOC has increased and the driveline disconnect clutch remains in an open state. The engine also remains in an off state.

At time T ₄ , the vehicle mass is increased. The vehicle mass may increase when the driver or anyone, for example, adds cargo or occupants to the vehicle. The vehicle speed remains at zero and the engine remains off. The desired torque converter impeller torque remains at a lower level and the energy storage device SOC remains unchanged. The driveline disconnect clutch also remains in an open condition.

At time T ₅ , the driver releases the brake pedal and the DISG output torque increases as the desired torque converter impeller torque increases. The desired torque converter impeller torque increases in response to the driver releasing the brake and increasing the driver demand torque. The energy storage device SOC begins to decrease as the DISG applies torque to the vehicle driveline. The vehicle speed starts to increase gradually. However, as the vehicle mass has increased, the vehicle is accelerating at a lower rate. The controller begins to estimate the change in vehicle mass based on the torque applied to the driveline and the rate of vehicle acceleration.

Between time T ₅ and time T ₆ , the engine is automatically restarted in response to the torque converter impeller torque increasing to more than one threshold level. The driveline disconnect clutch is also closed in response to the torque converter impeller torque being greater than a threshold level. Of the Energy storage device SOC decreases and the DISG provides torque to the driveline.

At time T ₆ , the driver reduces the driver request torque and applies the vehicle brake. The engine remains in operation and the driveline disconnect clutch remains engaged so that the engine can provide braking during vehicle deceleration. The engine remains in operation as the vehicle mass has increased and because the energy storage device SOC is less than the threshold level 1002 , As a result, the driveline disconnect clutch opening timing may be delayed or retarded as the vehicle mass increases. Likewise, the driveline disconnect clutch opening timing may be advanced as the vehicle mass decreases. The vehicle mass remains at the higher level and the vehicle slows down towards zero speed. The energy storage device SOC increases as the vehicle slows down.

At time T ₇ , the driveline disconnect clutch is opened and the engine is stopped as the vehicle speed approaches zero. The vehicle brake remains in an applied condition and the desired torque converter impeller torque remains at a lower level. The vehicle mass remains unchanged when the vehicle is stopped.

At time T ₈ , the brake pedal is released by the driver and the engine is started automatically. In the present example, the driveline disconnect clutch is opened when the engine is stopped; however, in some examples, the driveline disconnect clutch remains closed so that the prime mover and DISG simultaneously accelerate to operating speed. The engine is restarted upon release of the brake pedal in response to the increased vehicle mass. In this way, it may be possible to reduce the possibility of accelerating the vehicle at less than a desired rate since the engine and the DISG are available when the brake pedal is released. Further, the engine and DISG may apply a creep torque that drives the vehicle at the same rate as when the vehicle is unloaded and when powered only via the DISG when the driver is not depressing the vehicle drive pedal.

The desired torque converter impeller torque is also increased in response to the increase in estimated vehicle mass. The desired torque converter impeller torque is increased such that the vehicle accelerates in a similar manner as when the vehicle is accelerating at a time when the vehicle mass is less (eg, at time T ₁ ). Thus, for a similar accelerator pedal input, the vehicle accelerates similarly as when the vehicle mass is reduced and the accelerator pedal input is the same. In this way, the driver may experience a similar vehicle acceleration for an equivalent accelerator pedal input even if the vehicle mass changes.

Consequently, the methods and systems of 1 - 3 and 9 - 10 operating a hybrid vehicle, comprising: adjusting actuation of a driveline disconnect clutch in response to a change in vehicle mass. The method further comprises adjusting the engine stop timing in response to the change in vehicle mass. The method includes where adjusting the actuation of the driveline disconnect clutch comprises decelerating the driveline disconnect clutch open timing in response to an increase in vehicle mass. The method includes where adjusting the actuation of the driveline disconnect clutch includes advancing the driveline disconnect clutch open timing in response to a decrease in vehicle mass. The method further includes adjusting an energy storage device charge state threshold in response to the vehicle mass. The method includes where adjusting the energy storage device charge state threshold includes increasing the energy storage device charge state threshold in response to the vehicle mass.

In another example, the methods and systems of 1 - 8th operating a hybrid vehicle, comprising: adjusting actuation of a driveline disconnect clutch in response to a change in vehicle mass; and automatically stopping an engine at a time responsive to the change in vehicle mass. The method further includes not restarting the engine in response to the vehicle mass when the vehicle mass is a first vehicle mass. The method further includes restarting the engine in response to the vehicle mass when the vehicle mass is a second vehicle mass. The method includes where the second vehicle mass is greater than the first vehicle mass. The method further includes providing at least a portion of a creep torque across the engine after restarting the engine.

In some examples, the method includes providing creep torque only via a DISG when the engine is not restarted and when the hybrid vehicle is being moved. The method further comprises the Setting a desired torque converter impeller torque in response to the change in vehicle mass. The method includes where adjusting the desired torque converter impeller torque comprises increasing the desired torque converter impeller torque as the change in vehicle mass increases vehicle mass. The method includes where adjusting torque converter impeller torque includes decreasing torque converter impeller torque as the change in vehicle mass decreases vehicle mass.

In another example, the methods and systems of 1 - 8th operating a hybrid vehicle, comprising: adjusting actuation of a driveline disconnect clutch in communication with an engine in response to a change in vehicle mass; automatically stopping the engine in response to a first energy storage device state of charge being greater than a first threshold state of charge, wherein the first threshold state of charge is based on a first vehicle mass prior to the change in vehicle mass; and automatically stopping the engine in response to a second energy storage device state of charge being greater than a second threshold state of charge, wherein the second threshold state of charge is based on a second vehicle mass after the change in vehicle mass. Thus, the driveline disconnect clutch may be actuated based on vehicle mass to improve vehicle performance.

In some examples, the method includes where the second threshold state of charge is greater than the first threshold state of charge. The method includes where the second vehicle mass is greater than the first vehicle mass. The method includes where the driveline disconnect clutch is open when the engine is stopped. The method also includes where the driveline disconnect clutch is closed when the engine is stopped.

Regarding 11 1 is a flowchart of a method for starting an engine via a first electric machine or a second electric machine. The procedure of 11 can in a non-volatile memory of the control unit 12 from 1 - 3 be stored as executable instructions.

at 1102 determines the procedure 1100 Vehicle operating conditions. The vehicle operating conditions may include, but are not limited to, engine speed, DISG speed, vehicle speed, driveline torque request, engine coolant temperature, and driveline disconnect clutch actuation state (eg, open, partially open, or closed). The procedure 1100 go to 1104 continue after the operating conditions are determined.

at 1104 assess the procedure 1100 Whether there are conditions to stop the engine rotation or not. In one example, engine rotation may stop when the desired driveline torque (eg, a combined torque provided via the engine and / or the DISG) is less than a threshold torque amount. If the procedure 1100 judged that conditions are not present to stop the engine rotation, the procedure goes 1100 to 1106 further. Otherwise, the procedure goes 1100 to 1110 further.

at 1106 operates the procedure 1100 the engine. The engine is operated via the supply of spark and / or fuel to the engine based on engine operating conditions. In some examples, where the engine is a diesel engine or a homogeneous charge compression ignition (HCCI) engine, the engine may be operated without a spark. The procedure 1100 go to 1108 continue after the engine is running.

at 1108 provides the procedure 1100 a torque from the engine to the vehicle wheels. The engine torque may be delivered to the vehicle wheels by closing the driveline disconnect clutch and directing the engine output through the transmission to the vehicle wheels. In some examples, the engine and DISG torque may be delivered simultaneously to the vehicle wheels. The procedure 1100 proceeds to the end after the engine torque is delivered to the vehicle wheels.

at 1110 stops the procedure 1100 the engine rotation and opens or disengages the driveline disconnect clutch. Engine rotation may be stopped by preventing fuel and / or air flow to the engine cylinders. The procedure 1100 go to 1112 continue after the engine is stopped. It should be noted that in response to a driver request while the engine is stopped, the DISG may continue to provide torque to the vehicle wheels.

at 1112 assess the procedure 1100 Whether there are conditions to restart the engine or not. In one example, the Engine are restarted when the driveline torque command exceeds a threshold torque amount. In other examples, the engine may be started when a temperature of a catalyst is reduced to less than a threshold temperature. If the procedure 1100 judged that there are selected conditions for restarting the engine, the method goes 1100 to 1114 further. Otherwise, the procedure returns 1100 to 1104 back.

at 1114 determines the procedure 1100 an available amount of torque from the DISG. The amount of torque available from the DISG is based on the rated DISG torque, battery state of charge, DISG speed, and DISG temperature. A table describing the torque available from the DISG is stored in memory and is indicated by the battery state of charge (eg, battery voltage and amp hour rating), DISG speed, and DISG temperature. The table returns the amount of available torque from the DISG. The procedure 1100 go to 1116 after determining the amount of available DISG torque.

at 1116 assess the procedure 1100 whether the DISG has the capacity to start the engine and supply the desired amount of torque or not. In one example, the desired amount of torque is determined, at least in part, by an accelerator pedal that the driver can adjust to vary the desired driveline torque. The torque for starting the engine may be determined empirically and stored in memory in a table or function. The table or function may be indexed about the engine temperature and time since the last engine stop. The table gives a torque to achieve a desired engine cranking speed (eg., 250 min ^-1) from the zero speed. The engine startup torque is added to the desired driveline torque provided by the driver, and the amount of available DISG torque is subtracted from the sum of the engine startup torque and the desired driveline torque. If the result is positive, the DISG lacks the capacity to provide the torque to start the engine and to provide the desired driveline torque. Consequently, the procedure goes 1100 to 1124 further. If the result is negative, the DISG has the capacity to provide the torque to start the engine and to provide the desired driveline torque. Therefore, the procedure goes 1100 to 1118 further.

at 1118 assess the procedure 1100 Whether an engine start was requested or not. If so, the procedure goes 1100 to 1120 further. Otherwise, the procedure goes 1100 to 1122 further. The procedure 1100 may judge that an engine start request is being made when, for example, an engine torque request is increasing or when a driver releases a brake pedal.

at 1120 provides the procedure 1100 the DISG torque to the vehicle wheels and the engine. The DISG torque is delivered to the engine via closing the driveline disconnect clutch and transmitting the torque from the DISG to the engine. The driveline disconnect clutch may partially close to control engine speed during engine startup. The engine may be a cranking speed (eg., 250 min ^-1) position, or to a base idle speed (eg., 800 min ^-1) before fuel and spark are supplied to the combustion engine. The procedure 1100 returns 1104 after the DISG torque is delivered to the engine and to the vehicle wheels.

at 1122 provides the procedure 1100 the DISG torque only to the vehicle wheels. The DISG torque delivered to the vehicle wheels may be based on an accelerator pedal input and / or an input from a control unit. The procedure 1100 returns 1104 back after the DISG torque is delivered to the vehicle wheels.

at 1124 assess the procedure 1100 Whether there is an engine start request or not. An engine start request may occur as with 1118 is described. When an engine start is requested, the procedure goes 1100 to 1126 further. Otherwise, the procedure goes 1100 to 1122 further.

at 1126 starts the procedure 1100 the engine via a second electric machine having a lower power output capacity than the DISG. For example, the engine may be started via a conventional starter including a pinion shaft and a pinion that is selectively engaged with the engine flywheel to start the engine. The driveline disconnect clutch is closed when the second electric machine alone provides torque for rotating the engine. Further, at 1126 Fuel and a spark are supplied to the engine to initiate combustion in the engine so that the engine rotates under its own power. The method 1100 go to 1128 Continue after the engine has started.

at 1128 moves the procedure 1100 the driveline disconnect clutch to allow the transmission of torque from the engine to the vehicle wheels. In one example, the engine speed is increased until the engine speed matches the speed of the DISG. The driveline disconnect clutch is closed when the engine speed is equal to the DISG speed to reduce the possibility of introducing torque disturbance into the driveline. The procedure 1100 continues to the end after the engine is started delivering torque to the vehicle wheels.

It should be noted that the procedure of 11 FIG. 5 shows only one example of starting an engine alone via a lower power capacity electric machine (starter motor) or solely via a higher capacity electric machine (DISG). Other examples are also foreseen. For example, if both the lower power capacity DISG and the starter motor are operational, the lower power capacity DISG and the starter motor may start the engine during various operating conditions. However, if the DISG is deactivated, the lower power capacity starter may start the engine after the engine has been automatically stopped from rotating in conditions in which the DISG would otherwise start the engine. For example, the lower power capacity starter may start the engine when the DISG is able to start the engine and provide torque to the driveline without being deactivated. On the other hand, if the lower power capacity starter motor is deactivated, the engine may be started by the DISG when the driveline torque request is at a lower threshold level because the lower power capacity starter motor is not available.

Regarding 12 FIG. 15 is a diagram of an example sequence for starting an engine according to the method of FIG 11 shown. The vertical markers T ₁₀ -T ₁₇ represent points of interest in the sequence of interest. The sequence of 12 can through the system of 1 - 3 to be provided.

The first diagram from the top of 12 represents the DISG torque as a function of time. The x-axis represents time and time increases from the left side of the figure to the right side of the figure. The Y axis represents the DISG torque and the DISG torque increases in the direction of the Y axis arrow. The horizontal line 1202 represents a set of available DISG torque. The horizontal line 1204 represents an amount of torque that the DISG can deliver to the transmission input while the DISG is starting the engine. The difference between the horizontal lines 1202 and 1204 represents an amount of torque for starting the engine to start.

The second diagram of 12 represents the engine speed as a function of time. The x-axis represents time and time increases from the left side of the figure to the right side of the figure. The Y-axis represents the engine speed and the engine speed increases in the direction of the Y-axis arrow.

The third diagram from the top of 12 represents the driveline disconnect clutch state (eg, open or closed) as a function of time. The x-axis represents time and time increases from the left side of the figure to the right side of the figure. The Y-axis represents the driveline disconnect clutch state and the driveline disconnect clutch state is open at the top and closed near the X-axis as indicated.

The fourth diagram from the top of 12 represents the state of the low output starter as a function of time. The X axis represents time and time increases from the left side of the figure to the right side of the figure. The Y axis represents the state of the low output starter and the state of the low output starter is engaged when the curve is at a higher level and disengaged when the curve is at a lower level.

The fifth diagram from the top of 12 represents the engine start request state as a function of time. The X axis represents time and time increases from the left side of the figure to the right side of the figure. The Y axis represents the engine start request state, and the engine start request state is activated to start or run when the curve is at a higher level. The engine start request is not activated or indicates an engine stop when the curve is at a lower level.

At time T ₁₀ , the DISG torque is at a lower level in response to a low driveline torque request (not shown). The driveline torque request may be from an accelerator pedal or other device and may be responsive to driver input. The engine is too stopped and the driveline disconnect clutch is open. The lower power starter is not engaged and there is no engine start request.

At time T ₁₁ , an engine start request is delivered while the DISG torque is less than a threshold 1204 , The engine start request may be performed in response to a battery state of charge (SOC) or other condition. The low output starter remains inactive and the driveline disconnect clutch closes shortly thereafter. Closing the driveline disconnect clutch transfers torque from the DISG to the engine, thereby cranking the engine. The engine starts shortly after the DISG is at least partially closed. The driveline disconnect clutch may grind while the engine is cranking and during engine cranking from engine stop to DISG speed.

At time T ₁₂ , the engine start / run request transitions to a low level in response to vehicle operating conditions (eg, a charged battery and an applied vehicle brake pedal). The driveline disconnect clutch is opened in response to the engine start / run request and the engine is stopped. The DISG continues to deliver torque to the vehicle powertrain.

Between time T ₁₂ and time T ₁₃ , the DISG output torque increases in response to an increased driver request torque (not shown). The engine remains off and the driveline disconnect clutch remains open.

At time T ₁₃ , the engine start / run request is activated in response to the battery SOC being less than a threshold charge level (not shown). The low output starter is activated as indicated because the DISG torque is at 1204 is greater than the threshold torque. The driveline disconnect clutch is open while the engine is cranked by the lower output starter. The low output starter is deactivated when the engine speed exceeds the engine cranking speed.

At time T ₁₄ , the driveline disconnect clutch is closed after the engine speed reaches the DISG speed. The engine start / run request remains activated and both the DISG and the engine provide torque to the vehicle driveline.

At time T ₁₅ , the engine start / run request transitions to a lower level to indicate that the engine is to be stopped. Shortly thereafter, in response to the engine start / run request transitioning to a lower level, the engine is stopped and the driveline disconnect clutch is opened. The DISG continues to deliver torque to the vehicle powertrain.

At time T ₁₆ , the engine start / run request is activated in response to the driver request torque exceeding a threshold torque (not shown). The engine is restarted so that the engine can output torque to the driveline to boost the DISG torque. The low output starter is indented in response to the engine start / run request transitioning to a higher level. The low output starter is disengaged in response to engine speed exceeding a threshold speed.

At time T ₁₇ , the driveline disconnect clutch is closed in response to the engine speed reaching the DISG speed. The engine and DISG provide torque to the vehicle driveline after the driveline disconnect clutch is closed.

In this way, the engine may be started via the DISG or the lower output starter. The lower power starter allows the DISG to output a greater amount of torque to the driveline than would be possible if only the DISG had the ability to crank the engine. Further, the lower output starter allows the engine speed to reach the DISG speed before the driveline disconnect clutch is closed so little torque disturbance in the vehicle driveline can be noticed.

Consequently, the methods and systems of 1 - 3 and 11 - 12 starting an engine, comprising: during a first condition, starting an engine with a first electric machine while a driveline disconnect clutch is closed; and during a second condition, starting the engine with a second electric machine while the driveline disconnect clutch is open. The method includes where the second electric machine has a lower power output capacitance than the first electric machine. The method includes where the first electric machine includes a driveline integrated starter / generator (DISG). and that the driveline disconnect clutch has a first side mechanically coupled to a dual mass flywheel and a second side mechanically coupled to the DISG.

In some examples, the method includes where the first condition is a desired driveline torque that is less than a driveline torque during the second condition. The method includes where the driveline disconnect clutch is opened in response to a desired driveline torque. The method includes where the driveline disconnect clutch is closed when a sum of a desired driveline torque and an engine starting torque is greater than a threshold torque amount. The method includes where the first electric machine is located downstream of an engine and provides torque through a torque converter that rotates the vehicle wheels, and that the second electric machine is disposed on the engine and at an engine cranking speed that is lower than the engine idle speed, does not provide torque through the torque converter to rotate the vehicle wheels.

In other examples, the methods and systems of 1 - 3 and 11 - 12 starting an engine, comprising: starting an engine via a first electric machine when a desired torque request is less than a first threshold amount; Starting the engine via the second electric machine when the desired torque request is greater than the first threshold amount; and providing torque sufficient to rotate the vehicle wheels only via the first electric machine during selected operating conditions. Consequently, various electric machines may start the engine during various conditions.

The method includes where the first electric machine is a driveline integrated starter / generator (DISG) and the DISG is disposed in the hybrid vehicle driveline at a location between the driveline disconnect clutch and a transmission. The method includes where the DISG provides torque to start rotation of the stopped engine via at least partially closing the driveline disconnect clutch. The method further includes decoupling the second electric machine from the engine when the engine speed reaches a threshold speed. The method includes where the second electric machine comprises a pinion shaft and a pinion. The method includes where the first threshold amount varies with the battery state of charge. The method also includes where the first threshold amount varies with the speed of the first electric machine.

The methods and systems of 1 - 3 and 11 - 12 also provide a hybrid vehicle system comprising: an engine; a starter that is selectively engaged with the engine and includes a pinion; a dual mass flywheel (DMF) having a first side mechanically coupled to the engine; a driveline disconnect clutch having a first side mechanically coupled to a second side of the dual mass flywheel; a driveline integrated starter / generator (DISG) having a first side coupled to a second side of the driveline disconnect clutch; and a controller having nonvolatile instructions executable to start the engine via the starter during a first start and via the DISG during a second start.

In some examples, the hybrid vehicle system further includes additional instructions for starting the engine via the starter in states of desired torque that is greater than a threshold. The hybrid vehicle system includes where the engine is started by rotating the engine via the DISG, and further including additional commands to uncouple the DISG from the engine after a predetermined number of combustion events. The hybrid vehicle system further includes additional instructions for coupling the engine to the DISG after the engine speed reaches the DISG speed. The hybrid vehicle system includes the available power output from the starter being lower than the available power output from the DISG. The hybrid vehicle system further includes additional commands to automatically stop the engine and that the engine is started via the DISG based on an available amount of DISG output torque.

Regarding 13 FIG. 10 is a flowchart of a method of adjusting fuel injection to provide a desired engine speed curve during engine startup. The procedure of 13 can be used as executable instructions in a nonvolatile memory of the 1 - 3 shown control unit 12 be saved.

at 1302 assess the procedure 1300 Whether an engine start is requested and the driveline disconnect clutch is disengaged or not. The procedure 1300 may judge that engine startup is desired when an engine start variable is enabled in memory. The procedure 1300 can judge that Driveline disconnect clutch is disengaged when a driveline disconnect clutch state variable in the memory is not activated. If the procedure 1300 judges that an engine start is desired and a driveline disconnect clutch is not engaged, the method goes 1300 to 1304 further. Otherwise, the procedure goes 1300 to 1316 further.

at 1304 determines the procedure 1300 Operating conditions. The operating conditions may include, but are not limited to, the DISG speed, engine temperature, time since the engine stall stop, and driveline disconnect condition. The procedure 1300 go to 1306 continue after the operating conditions are determined.

at 1306 determines the procedure 1300 the desired engine speed based on the torque converter impeller speed. Furthermore, a desired cylinder air charge may occur 1306 be determined so that the desired engine speed can be achieved. In one example, the desired engine speed after engine cranking (eg, from cranking speed to a desired idle speed) is set to the torque converter impeller speed. Thus, after engine startup during engine startup, engine speed is controlled to torque converter impeller speed such that the driveline disconnect clutch may be closed to transmit engine torque to the vehicle wheels without generating a torque disturbance. The engine may be cranked by rotating the engine with a starter other than a DISG (eg, a lower output starter), if desired. The procedure 1300 go to 1308 after the desired engine speed is selected. It should be noted that the torque converter impeller speed is equivalent to the DISG speed because the DISG is coupled to the torque converter impeller.

at 1308 the fuel injection is set for the first combustion event. In one example, where the engine includes a nearly centrally located fuel injector at the top of the combustion chamber, fuel is injected into at least one cylinder via a single fuel pulse during a compression stroke of the cylinder and during a single cycle of the cylinder. The injected fuel then participates in a first combustion event since the engine stop for the cylinder receiving the fuel. After the single fuel pulse is injected into the cylinder, fuel injections may be injected during startup in a series of pulses during the intake and compression strokes of the cylinder receiving the fuel, as at 1310 described. In one example, a single fuel pulse is injected into each of a predetermined number of engine cylinders during the compression strokes of the cylinders. Consequently, the fuel is injected into each of the predetermined number of cylinders in one or more pulses during a cycle of the cylinder receiving the fuel. For example, for a four-cylinder engine, two engine cylinders receive a single injection of fuel during the respective compression strokes of the cylinders receiving the single injection of fuel. The other two engine cylinders receive multiple injections of fuel during the intake and / or compression strokes of the cylinder receiving the fuel.

In a second example in which the engine includes a fuel injection disposed on the side of the combustion chamber, a plurality of fuel injections for each cylinder are added to a predetermined number of engine cylinders during the compression stroke of the cylinder receiving the fuel for the first combustion event Cylinder supplied since the engine stop. After a predetermined number of cylinders receive multiple fuel injections during the compression stroke of the cylinder receiving the fuel, multiple injections of fuel may be supplied to each cylinder during the intake and / or compression stroke of the cylinder receiving the fuel. Also, the position of the engine throttle at 1308 be set on the basis of the desired engine speed. In one example, the engine throttle opening amount is increased as the desired engine speed increases during engine cranking. The procedure 1300 go to 1310 after the fuel is injected for the first combustion events of each engine cylinder.

at 1310 puts the procedure 1300 a split fuel injection timing and divided fuel amounts based on the desired engine speed and a rotational speed difference between the actual engine speed and the desired engine speed. In particular, (z. B. between a cranking speed of 250 min ^-1 and 400 min ^-1) for each engine cylinder during the compression stroke of each cylinder receiving the fuel supplied to two or more injections at lower engine speeds. At medium engine speeds (eg., Between 400 and 700 min ^-1 min ^-1 ), multiple fuel injections are delivered during both the intake and compression strokes of each cylinder receiving the fuel. At higher engine speeds (eg., 700 min ^-1 to 1000 min ^-1) a plurality of fuel injections are supplied only during the intake stroke of the cylinder receiving the fuel. Of course, the lower, intermediate, and higher engine speeds may differ between applications. The lower engine speed can be used for other applications, for example, range from 200 min ^-1 to 300 min ^-1, the average engine speed may be between 300 lie min ^-1 and 800 min ^-1, and the higher engine speed may be between 800 min ^-1 to 1100 min ^-1 lie. Thus, when the desired engine speed is a higher engine speed, the fuel injection timing is adjusted to provide multiple fuel injections only during the intake stroke of the cylinder receiving the fuel when the engine reaches the desired engine speed. When the desired engine speed is an average engine speed, the fuel injection timing is adjusted to provide multiple fuel injections during the intake and compression strokes of the cylinder receiving the fuel. The split fuel injection timing at higher engine speeds provides improved fuel mixing and reduced engine emissions. The split fuel injection during the compression and intake strokes provides improved combustion stability and reduced possibility of engine misfire.

When the engine speed increases to the desired idling speed during the engine startup of the starter speed (z. B. 250 min ^-1), the amount of time between the end of injection (EOI, end of injection) (for. Example, the time, to which the last fuel pulse injected into a cylinder during a cycle of the cylinder takes place) and spark initiation is kept substantially constant (eg, ± 3 degrees). As the time between different crankshaft positions decreases as engine speed increases, the EOI timing relative to the crankshaft timing is advanced to maintain a substantially constant amount of time (eg, ± 0.05 seconds) between the EOI and the spark initiation maintain. Further, when multiple fuel injections are performed, the timing of each of the fuel injections during one cylinder cycle may be advanced as the engine speed increases. Thus, the start of fuel injection (SOI) may be advanced during a cylinder cycle as engine speed increases during engine cranking.

If the desired engine speed is greater than the actual engine speed, the fuel injection amounts are increased by increasing the fuel injection duration. Additional air may also be supplied to the engine via the opening of the throttle. If the desired engine speed is less than the actual engine speed, the fuel injection quantities are reduced by shortening the fuel injection duration. The engine air amount can be reduced by closing the throttle. Further, the fuel injection timing and the fuel amounts may be adjusted in response to driveline disconnect clutch operating conditions to preventively adjust the fuel injection timing. For example, if the driveline disconnect clutch closes and the driveline disconnect clutch engine side rotates slower than the DISG side of the driveline disconnect clutch, the fuel injection amount may be increased to accelerate the engine closer to the DISG speed and thereby reduce driveline torque interference. On the other hand, if the driveline disconnect clutch closes and the driveline disconnect clutch engine side rotates faster than the DISG side of the driveline disconnect clutch, the fuel injection amount may be reduced to slow the engine to near DISG speed. Further, as the driveline disconnect clutch is opened, the fuel injection amount may be reduced as a function of driveline disconnect clutch application force to slow the engine down to idle speed and thereby reduce driveline torque disturbances. Also, when the driveline disconnect clutch is opened, the fuel injection amount as a function of the driveline disconnect clutch application force may be increased to accelerate the engine to idle speed and thereby reduce driveline torque disturbances.

In some examples, the fuel injection timing of an engine cylinder is set to a stroke of a cylinder that changes as the engine speed changes. For example, when a speed difference between the actual and desired engine speeds increases, the method adjusts 1300 the fuel from a compression stroke to an intake stroke. By changing the injection stroke based on a speed difference between the actual and desired engine speeds, it may be possible to improve the air / fuel mixture and promote more complete combustion so that the speed difference can be reduced.

Additionally, the engine throttle position may be adjusted in response to the timing at which fuel is injected into a cylinder. For example, a duct throttle may be partially closed to increase charge motion when fuel is injected only during an intake stroke. The duct throttle may be partially opened when the fuel injection transits from injecting fuel during a compression stroke to inject fuel during an intake stroke. Further, the amount of fuel injected into the cylinder during the cylinder cycle is set on the basis of an amount of air flowing through a throttle valve. The procedure 1300 go to 1312 after the fuel injection timing is set.

at 1312 puts the procedure 1300 the spark timing in response to the state of the driveline disconnect clutch and the speed difference between the desired engine speed and the actual engine speed. Specifically, when the engine speed at substantially the DISC speed is (z. B. ± 100 min ^-1), the spark is retarded to a level to produce a zero torque on the driveline clutch. Further, the spark retard may also be provided based on the speed difference between the DISG and the engine. As the speed difference between the engine and the DISG is reduced, the amount of spark retard is increased.

at 1314 assess the procedure 1300 whether or not the driveline disconnect clutch has been closed to a threshold amount (eg, 80% of the clutch holding torque is provided). The driveline disconnect clutch may be closed when the engine speed is within a predetermined rotational speed of the torque converter impeller speed such that driveline torque disturbances may be reduced. If the procedure 1300 judges that the driveline disconnect clutch has been closed to a threshold level, the procedure goes 1300 to 1316 further. Otherwise, the procedure returns 1300 to 1304 back.

at 1316 adjusts the procedure 1300 spark timing and proceeds to inject fuel in a single fuel injection during a cycle of a cylinder based on a number of combustion events since the engine stop or based on a torque ratio. After the driveline disconnect clutch closes, the process can 1300 For example, during a cylinder cycle after 10 combustion events, transition from split fuel injection to a single fuel injection. Alternatively, the method 1300 from the split fuel injection to the single fuel injection during a cylinder cycle after the spark timing is advanced to a time point when a torque ratio between the spark timing and the fuel injection timing is less than a threshold amount. The procedure 1300 proceeds to the end after the fuel injection timing and spark timing are transitioned to base timings, which are empirically determined and stored in memory.

Regarding 14 FIG. 10 is a diagram of an example sequence for supplying fuel to an engine according to the method of FIG 13 shown. The sequence of 14 can through the system of 1 - 3 to be provided.

The first diagram from the top of 14 represents the fuel injection timing for cylinder number one. The x-axis represents the cylinder stroke for cylinder number one and individual cylinder strokes are indicated by representative letters. For example, the intake stroke is represented by I, the compression stroke is represented by C, the power stroke is represented by P, and the exhaust stroke is represented by E. The Y-axis represents the fuel injection.

The second diagram from the top of 14 represents the desired torque converter impeller speed as a function of the stroke of cylinder number one. The X-axis timing is consistent with the timing of the first graph from the top of the figure. The Y axis represents the desired torque converter impeller speed and the desired torque converter impeller speed increases in the direction of the Y axis arrow.

The third diagram from the top of 14 represents the desired engine speed as a function of the stroke of cylinder number one. The X-axis timing is consistent with the timing of the first chart from the top of the figure. The Y axis represents the desired engine speed and the desired one Engine speed increases in the direction of the Y-axis arrow.

The fourth diagram from the top of 14 represents the actual engine speed as a function of the stroke of cylinder number one. The X-axis timing is consistent with the timing of the first chart from the top of the figure. The Y-axis represents the actual engine speed and the actual engine speed increases in the direction of the Y-axis arrow.

The fifth diagram from the top of 14 represents a difference between the desired engine speed and the actual engine speed (delta engine speed) as a function of the stroke of cylinder number one. The X-axis timing is consistent with the timing of the first graph from the top of the figure. The Y-axis represents the desired engine speed and the desired engine speed increases in the direction of the Y-axis arrow.

At time T ₁₈ , the engine is stopped and the desired torque converter impeller speed is zero. The engine rotates after T ₁₈ in the cycle by the different stroke of the number one cylinder. A first single fuel injection amount is delivered directly to cylinder number one during the compression stroke of cylinder number one. The engine begins to accelerate from a first combustion event during the first compression stroke since the engine stall.

At time T ₁₉ , two fuel injections are delivered during the second compression stroke of cylinder number one. Fuel injection transitions to two injections in response to a speed difference between the desired engine speed and the actual engine speed. Further, fuel injection is provided during a cylinder stroke that depends on the speed difference between the actual and desired engine speeds. In one example, the fuel injection timing for the cylinder stroke is stored in a table based on the difference between the actual and desired engine speeds and outputs a cylinder stroke based on the speed difference. By adjusting the cylinder stroke at which fuel injection takes place based on a difference between the actual and desired engine speeds, it may be possible to improve fuel mixing and engine speed control during engine startup.

Between time T ₁₉ and time T ₂₀ , the fuel injection timing is further adjusted in response to the difference in the desired engine speed and the actual engine speed. It can be observed that the fuel injection from injecting fuel changes twice during a compression stroke of the cylinder for injecting fuel once during an intake stroke and once during a compression stroke. Further, the fuel injection for injecting fuel overflows twice during an intake stroke.

At time T ₂₀ , the engine speed error between the desired engine speed and the actual engine speed is zero, and fuel is injected once per cylinder cycle. In this manner, the fuel injection timing may be adjusted to supply fuel during various engine strokes in response to the engine speed error. Further, the fuel injection timing and the spark timing may be adjusted in response to the driveline disconnect clutch state or force as described with reference to FIG 13 discussed.

The methods and systems of 1 - 3 and 13 - 14 also provide for adjusting the cylinder air charge of an engine, comprising: positioning a throttle for an engine start; and adjusting a fuel injection timing of a cylinder to a stroke of the cylinder that changes as a difference between a desired engine speed and an actual engine speed changes, and adjusting an amount of fuel supplied to the cylinder in response to an amount of air that flows through the throttle. The method includes where the stroke of the cylinder changes from a compression stroke to an intake stroke. The method includes where the throttle is a duct throttle.

In some examples, the method further includes closing the duct throttle at least partially during fuel injection during a compression stroke. The method further comprises the duct throttle valve being open during fuel injection during an intake stroke of the cylinder. The method also includes where the fuel injection timing provides at least two fuel injections during one cycle of the cylinder. The method includes where the fuel injection timing is provided to a fuel injector that injects fuel directly into the cylinder.

The methods and systems of 1 - 3 and 13 - 14 also provide for adjusting the cylinder air charge of an engine, comprising: positioning a throttle for an engine start; Supplying a spark to a combustion chamber of a cylinder during a cycle of the cylinder; and setting a fuel injection timing to be a substantially constant amount of time between the spark and an end of the fuel injection timing maintain as the engine speed increases during engine cranking while injecting a plurality of fuel pulses during the cycle of the cylinder; and adjusting an amount of fuel supplied to the cylinder in response to an amount of air flowing through the throttle. In this way, the combustion consistency can be maintained.

The method also includes advancing the fuel injection timing as the engine speed increases. The method further includes where the fuel injection timing is responsive to a desired engine speed and the desired engine speed is based on a torque converter impeller speed. The method further includes closing a driveline disconnect clutch when the engine speed is within a threshold speed of the torque converter impeller speed. The method includes where a cylinder stroke during which the plurality of fuel pulses are injected varies as the engine speed varies. The method further includes changing the spark timing during engine cranking. The method includes where the throttle is a duct throttle located downstream of an intake manifold.

The methods and systems of 1 - 3 and 13 - 14 Also include a hybrid vehicle system, comprising: an engine; a dual mass flywheel (DMF) having a first side mechanically coupled to the engine; a driveline disconnect clutch having a first side coupled to a second side of the dual mass flywheel; a driveline integrated starter / generator (DISG) having a first side coupled to a second side of the driveline disconnect clutch; and a controller having nonvolatile instructions executable to set the fuel injection timing to a cylinder in response to a desired engine speed based on a torque converter impeller speed while the torque converter impeller is not mechanically coupled to the engine. By adjusting the fuel injection timing based on the torque converter impeller speed, it may be possible to adjust the fuel injection timing so that the desired fuel injection timing is provided when the engine reaches the torque converter impeller speed. Such operation can improve engine emissions.

The hybrid vehicle system further includes additional instructions for closing the driveline disconnect clutch after the engine speed is within a threshold speed of the torque converter impeller speed. The hybrid vehicle system includes starting the engine by rotating the engine via a starter other than the DISG. The hybrid vehicle system further includes additional commands for adjusting the fuel injection timing to provide a substantially constant amount of time between the timing of a spark being supplied to a cylinder and the timing of the end of fuel injection being delivered to the cylinder during one cycle of the cylinder to maintain as engine speed increases during engine cranking and during injection of multiple fuel pulses during the cycle of the cylinder. The hybrid vehicle system further includes additional commands for setting the fuel injection timing of a cylinder to a stroke of the cylinder that varies as a difference between the desired engine speed and an actual engine speed varies, and adjusting an amount of fuel delivered to the cylinder in response on a lot of air flowing through the throttle. The hybrid vehicle system further includes additional instructions for injecting a single pulse of fuel into the cylinder during a compression stroke of the cylinder prior to a first combustion event of the cylinder since the engine stop.

Regarding 15 FIG. 12 is a flowchart of a method for starting an engine when the torque delivered via an electric machine can not provide a desired amount of torque after a gear shift. The procedure of 15 can as executable instructions in the non-volatile memory of the control unit 12 in 1 - 3 be saved.

at 1502 assess the procedure 1500 Whether a transmission upshift is desired or commanded or not. In one example, a transmission upshift command may be determined about the monitored state of a control variable that changes state in response to the vehicle speed, the request torque, and the currently selected gear. If the control variable indicates that transmission shifting is desired, the procedure goes 1500 to 1506 further. Otherwise, the procedure goes 1500 to 1504 further.

at 1504 determines the procedure 1500 the transmission output shaft speed and torque converter impeller speed for a next upcoming transmission shift based on the desired torque. In one example, the desired torque delivered via an accelerator pedal, the current selected transmission gear, and the vehicle speed are the basis for determining transmission output speed and impeller speed for a next transmission upshift. In particular, the transmission output speed and the next gear may be determined from the current selected gear and the vehicle speed at which it is planned that the transmission will shift up to the next gear at a desired engine torque level. A shift pattern may be empirically determined and stored in memory that outputs which gear is selected at a current vehicle speed at a desired torque level. The vehicle speed may be extrapolated to a future time based on the current vehicle speed and the rate of change or increase in vehicle speed according to the equation y = mx + b, where y is the projected vehicle speed, m is the vehicle speed slope, and b is the vehicle speed offset. Likewise, the desired impeller speed can be extrapolated to a future time. As the extrapolation time increases from the present time (eg, current time plus 0.2 seconds and assuming increasing vehicle speed and / or increasing desired torque), the shift pattern may shift up to a higher gear (e.g. from 1st gear to 2nd gear) when variables indexing the shift pattern change. The extrapolated amount of time the transmission shift takes place (eg, the projected shift time), as well as the new gear number, the extrapolated vehicle speed, and the extrapolated desired torque, are stored in memory as the selected transmission gear changes according to the shift pattern. The transmission output shaft speed is determined from the new gear (eg, the upshift gear), any axle ratio, and the vehicle speed. The transmission pump wheel speed can be predicted from the DISG speed since the DISG is mechanically coupled to the impeller. The procedure 1500 go to 1506 after the gear pump wheel speed and the transmission output shaft speed are determined.

at 1506 determines the procedure 1500 Transmission speeds (eg, impeller speed and output shaft speed) and torque request gear ratios in the next transmission upshift. In one example, the method determines 1500 the transmission output shaft speed based on the following equations: OSS = OSS_when_commanded + OSS_rateofchange · time_to_shift; Commanded_gear = gearfn (vs, dsd_tor); TSS_after_upshift = OSS · Commanded_gear;

Where OSS is the transmission output shaft speed, OSS_when_commanded the transmission output shaft speed when the upshift is commanded, time_to_shift is the amount of time it takes for a shift Commanded_gear is the active gear after the upshift is gearfn a function which returns the commanded gear vs. the vehicle speed, dsd_tor is the desired transmission input torque, and TSS_after_upshift is the transmission output shaft speed after upshifting. The function fn empirically holds certain gears with which the transmission works. The procedure 1500 go to 1508 continue after the transmission speeds and the gear ratio are determined after switching.

at 1508 determines the procedure 1500 the desired transmission output shaft torque and the desired transmission turbine shaft torque after an upshift. In one example, the method determines 1500 the transmission output torque and the turbine shaft torque based on the following equations: OUTq_dsd = outfn (accel_pedal, TSS_after_upshift); Turq_dsd = OUTq_dsd · mult + offset;

Where OUTq_dsd is the desired transmission output shaft torque, outfn is a function that returns the desired transmission output shaft torque, accel_pedal is the accelerator pedal position providing a desired torque, TSS_after_upshift is the transmission output shaft speed after upshift, Turq_dsd is the desired transmission turbine shaft torque , mult and offset are empirically determined parameters stored in functions indexed by the commanded gear, the transmission oil temperature, and the transmission output shaft speed. The procedure 1500 go to 1510 after the desired transmission output shaft torque and the desired transmission turbine shaft torque are determined after the upshift.

at 1510 assess the procedure 1500 Whether the torque converter clutch (TCC) is open after an upshift or not. In one example, the method assesses 1500 Whether the TCC is open after an upshift or not based on an empirically determined shift scheme stored in memory. For example, based on the current gear, the next planned gear and the desired torque, the shift pattern may be closed Plan torque converter. If the procedure 1500 judged that the TCC is open after the upshift, the answer is yes and the method 1500 go to 1512 further. Otherwise, the answer is no and the procedure 1500 go to 1514 further.

at 1512 determines the procedure 1500 the requested torque converter impeller torque. In one example, the requested torque converter impeller torque is retrieved from a table stored in memory. The table empirically determines torque converter impeller torque values indexed via the transmission output shaft speed after the upshift and the desired turbine wheel torque. The procedure 1500 go to 1516 after the requested impeller torque is determined.

at 1514 puts the procedure 1500 the desired torque converter impeller torque to the desired torque converter turbine torque, since the TCC is in a locked state. The procedure 1500 go to 1516 after the desired torque converter impeller torque is determined.

at 1516 assess the procedure 1500 Whether the desired torque converter impeller torque after the transmission upshift requires the engine to combust an air / fuel mixture or not. In one example, the method compares 1500 an amount of torque for which the DISG has the capacity to deliver it to the desired torque converter impeller torque at the current battery state of charge. If the desired torque converter impeller torque is greater than or within a threshold torque amount of the DISG torque capacity, the answer is Yes and the method 1500 go to 1520 further. Otherwise, the answer is no and the procedure 1500 go to 1518 further.

at 1518 can the procedure 1500 based on the current operating conditions allow the engine to stop the rotation, or the process 1500 may allow the engine to continue to burn an air / fuel mixture. In one example, where the engine has reached warm operating conditions, the engine stops rotating because the desired torque converter impeller torque does not require engine operation. The engine may continue to burn when the engine has not reached warm operating conditions. The procedure 1500 Goes to the end after the engine rotation is allowed or prevented based on the operating conditions that are not related to the transmission shifting.

at 1520 assess the procedure 1500 Whether the engine is to be started before the gearbox is upshifted or not. The engine may be started before the states of transmission clutches (eg, not including the driveline disconnect clutch 236 ) are adjusted so that the engine torque can be transmitted to the vehicle wheels at the end of the gear upshift. Alternatively, during the upshift, the engine may be started at a time when one or more transmission clutches change operating state. In one example, the engine may be started before the engine upshift commences and before the transmission clutches begin to change state when it is expected that the engine will take a longer amount of time to generate positive torque than that required to shift Gears expected time. If the procedure 1500 judges that it is desired to start the engine before the transmission upshift, the method goes 1500 to 1522 further. Otherwise, the procedure goes 1500 to 1526 further.

at 1522 starts the procedure 1500 the engine and engages the driveline disconnect clutch. The engine may be started by rotating the engine via a starter motor having a lower power output capacity than the DISG or by starting the engine via the DISG. Further, the transmission shifting may be delayed until the engine speed is synchronous with the DISG or impeller speed. Delaying transmission shifting may reduce the driveline torque disturbance that may occur as engine torque increases before the disengaging clutch is fully released. The procedure 1500 go to 1524 after the engine is started and the driveline disconnect clutch is released.

at 1524 switches the procedure 1500 the transmission high after the driveline disconnect clutch is engaged. The transmission may be upshifted by exerting and / or relieving pressure on one or more clutches that affect transmission of torque through the transmission. The procedure 1500 ends after the transmission is switched.

at 1526 prevents the procedure 1500 an engine stop when there are conditions other than the upcoming transmission upshift to stop engine rotation. In other words, when the engine is commanded without upshifting the transmission would stop, then stopping the engine rotation of the transmission is prevented. Additionally, the engine may be started at a time after the upshift has started (eg, during disengagement of the disengaging clutch (torque phase) or during application of the on-coming clutch (inertia phase)) to provide additional torque to the driveline, to meet the torque requirement. The engine and DISG torque may be adjusted to provide the desired amount of torque converter impeller torque. The procedure 1500 Goes to the end after the engine stop is prevented or after the engine is started after the upshift of the transmission begins.

In this way, the process can 1500 predict gearshift and desired torque converter impeller torque to determine when to close the driveline disconnect clutch and start the engine. The procedure 1500 may allow the engine torque to be seamlessly combined with the DISG torque to provide smooth acceleration during transmission shifting.

Regarding 16 FIG. 12 is a diagram of an example sequence for determining when to start an engine according to the method of FIG 15 shown. The sequence of 16 can through the system of 1 - 3 to be provided.

The first diagram from the top of 16 The desired driveline torque may be a desired torque converter impeller torque, a desired torque converter turbine torque, a desired wheel torque, or another driveline torque. The desired driveline torque may be determined by an accelerator pedal position or other input device. The solid curve 1602 represents the desired driveline torque. The dashed curve 1604 represents the predicted desired driveline torque (eg, the desired driveline torque after a gearshift). The y-axis represents the desired driveline torque, and the desired driveline torque increases in the direction of the y-axis. The X-axis represents the time and the time increases from the left side of the figure to the right side of the figure. The horizontal line 1606 represents a limit on the torque that can be delivered to the driveline via the DISG.

The second diagram from the top of 16 represents the transmission gear as a function of time. The Y-axis represents the gear and specific gears are indicated along the Y-axis. The X-axis represents the time and the time increases from the left side of the figure to the right side of the figure. The solid curve 1608 represents the current or actual transmission gear. The dashed curve 1610 represents the predicted or future transmission gear.

The third diagram from the top of 16 represents the desired engine state without transmission gearshift conditions as a function of time. The y-axis represents the desired engine state and the desired engine state is on for higher curve levels and off for lower curve levels. The X-axis represents the time and the time increases from the left side of the figure to the right side of the figure.

The fourth diagram from the top of 16 represents the desired engine state based on all conditions as a function of time. The Y axis represents the desired engine state and the desired engine state is on for higher curve levels and off for lower curve levels. The X-axis represents the time and the time increases from the left side of the figure to the right side of the figure.

The fifth diagram from the top of 16 represents the engine state as a function of time. The Y axis represents the engine state and the engine state is on for higher curve levels and off for lower curve levels. The X-axis represents the time and the time increases from the left side of the figure to the right side of the figure.

At time T ₂₁ , the desired driveline torque is greater than an amount of torque that may be delivered by the DISG to the driveline. The transmission is in 5th gear and the desired engine state and desired engine state without gear conditions are both at higher levels, indicating that it is desirable for the engine to operate. The engine state is at a higher level, indicating that the engine is working.

Between the time t ₂₁ and the time t _22, the desired drive train torque decreases in response to a decreasing driver input (not shown) from. The transmission shifts down from 5th to 2nd gear and the predicted gear changes to the current or Actual transmission gear ahead. The desired engine state without gear conditions and the desired engine state remain at higher levels.

At time T ₂₂ the desired transmission condition that the engine without a gear transition conditions (in response to vehicle and engine operating conditions such. B. applied brake, accelerator pedal goes without transition conditions to a lower level in response to the vehicle speed and the desired drive train torque, to indicate not applied, and a vehicle speed that is less than a threshold speed) can be stopped. The desired engine state also transitions to a lower level to indicate stopping the engine in response to operating conditions, including the predicted transmission gear. The engine is stopped in response to the desired engine condition.

Between time T ₂₂ and time T ₂₃ , the desired driveline torque levels off and then increases. The predicted gear increases from 2nd gear to 3rd gear as the desired driveline torque increases. The current gear is held in 2nd gear. The engine remains stopped because the desired engine state and engine condition remain at a lower level without gear conditions.

At time T ₂₃ , the desired engine state transitions to a higher level in response to the predicted desired driveline torque, which increases to greater than one level after shifting 1606 increases. The engine is started in response to the transition of the desired engine state. The desired engine condition without gear conditions remains at a lower level to indicate that the engine would remain off without increasing the desired driveline torque expected after gear shifting.

Between time T ₂₃ and time T ₂₄ , the desired driveline torque increases and then decreases in response to a reduced driver request (not shown). The desired driveline torque increases to less than 1606 and stays close to the level 1606 , The transmission shifts down from 5th gear to 3rd gear. The desired engine state and engine state without gear conditions remain at higher levels, so that the engine remains on.

At time T _24, the desired engine state passes without transition conditions to a lower level, to indicate that the engine in response to said desired powertrain torque, the vehicle speed and the applied brake may be (not shown) is stopped (not shown). The desired engine state, however, remains in response to the predicted desired driveline torque greater than one level 1606 increases, at a high level, as predicted for the gear shifting in the 4th gear. Consequently, an engine stop is prevented. Such conditions may exist when a vehicle is moving and when a driver is reducing (eg, decreasing or reducing) an accelerator pedal command.

Between time T ₂₄ and time T ₂₅ the desired powertrain torque increases and then decreases. The transmission shifts the gears between the 3rd and 5th gear in response to the driver request torque, the vehicle speed (not shown), and the brake state (not shown). The desired engine state without gear conditions and the desired engine state remain at higher levels in response to the desired driveline torque.

After time T ₂₅ , the desired driveline torque will be less than the level in response to a lower driver request (not shown) 1606 reduced. The desired engine condition without gear conditions and the desired engine condition transition to a lower level to indicate that the engine is to be stopped in response to the desired driveline torque, brake pedal condition (not shown), and vehicle speed (not shown). The engine is stopped in response to the desired engine condition.

Between the time t ₂₅ and the time t _26, the desired drive train torque is gradually increased and the predicted transmission speed rises from the 2nd gear to 3rd gear in response to the increasing desired powertrain torque. The desired engine state and engine state without gear conditions remain at a lower level and the engine remains stopped.

At time _T26 , the desired engine state transitions to a higher level and the engine is triggered in response to the engine increasing desired driveline torque and the predicted gear started. The desired engine condition without gear conditions remains at a lower level, indicating that the engine would not be started if the predicted desired driveline torque was not greater than a predicted gearshift gearshift 1606 , By starting the engine prior to actual gear shifting, it may be possible to provide the desired driveline torque after a shift.

In this manner, the engine may be started prior to gear shifting to provide a desired driveline torque after gear shifting. Further, the method predicts switching so that the engine may be started before the desired driveline torque is actually requested. Early starting of the engine may allow the engine to reach conditions under which it may output torque to meet the desired driveline torque.

The methods and systems of 1 - 3 and 15 - 16 to provide a method for starting an engine, comprising: predicting a desired torque after a transmission upshift; and starting rotation of a stopped engine when the predicted desired torque after the transmission upshift is greater than a threshold amount of torque. The method includes where the desired torque is a torque converter impeller torque and wherein the predicting the desired torque and starting the rotation are in conditions in which a driveline integrated starter / generator provides torque to the wheels and among which Transmission is in a forward gear and the vehicle moves. The method includes where the desired torque is predicted based on a predetermined transmission shift pattern.

In some examples, the method includes rotating the engine via a driveline disconnect clutch. The method includes disengaging the driveline disconnect clutch prior to rotating the engine. The method includes where the driveline disconnect clutch is disposed in the hybrid vehicle driveline between a dual mass flywheel and a driveline integrated starter / generator. The method includes where the engine is rotated in response to the predicted desired driveline torque before a transmission is shifted.

The methods and systems of 1 - 3 and 15 - 16 provide starting an engine, comprising: providing torque to a vehicle driveline via an electric machine; Scheduling a transmission upshift; and starting the rotation of a stopped engine in response to the planned transmission upshift when a desired torque after the planned transmission upshift is greater than a threshold torque amount, and the desired torque is based on a driveline integrated starter / generator torque after a transmission upshift to engage a power train Gearbox clutch relative to starting the engine based. The method includes where the electric machine is a driveline integrated starter / generator (DISG) and the DISG is disposed in the hybrid vehicle driveline at a location between a driveline disconnect clutch and a transmission.

In some examples, the method includes where the DISG provides torque for starting rotation of the stopped engine via at least partially closing the driveline disconnect clutch. The method further includes upshifting the transmission after starting rotation of the engine. The method also includes that the transmission is a double countershaft dual clutch transmission. The method includes where the transmission is an automatic transmission. The method further comprises allowing the engine to stop rotating when the desired torque after the transmission upshift timing for engaging the transmission clutch relative to engine starting is less than the threshold torque amount.

The methods and systems of 1 - 3 and 15 - 16 to provide a hybrid vehicle system comprising: an engine; a dual mass flywheel having a first side mechanically coupled to the engine; a driveline disconnect clutch having a first side mechanically coupled to a second side of the dual mass flywheel; a driveline integrated starter / generator having a first side mechanically coupled to a second side of the driveline disconnect clutch; and a controller having nonvolatile instructions executable to start the engine by closing the driveline disconnect clutch in response to a desired torque after a planned transmission upshift, wherein the engine is started in response to the scheduled transmission upshift before the transmission shifts. Such a system can improve driveline response time.

In one example, the hybrid vehicle system further includes additional instructions for inhibiting engine rotation stop as the engine rotates prior to the planned transmission upshift. The hybrid vehicle system includes starting the engine by rotating the engine via the driveline integrated starter / generator in response to closing the driveline disconnect clutch. The hybrid vehicle system further includes additional commands to upshift the transmission after the engine is started. The hybrid vehicle system further includes additional commands to allow the engine to stop rotating in response to the desired torque after the planned transmission upshift. The hybrid vehicle system further includes additional instructions for delaying engine startup until the scheduled transmission upshift is scheduled for a time less than a threshold amount of time.

Regarding 17 FIG. 12 is a flowchart of a method for starting an engine to reduce transmission input torque during a transmission shift. FIG. The procedure of 17 can be used as executable instructions in nonvolatile memory in the 1 - 3 be stored system shown. The procedure of 17 For example, the amplitude and / or number of times the torque changes are performed on a DISG during vehicle operation may decrease to limit the torque applied to a transmission during transmission shifting.

at 1702 assess the procedure 1700 Whether engine restart and transmission upshifting are desired or not. For example, an engine restart may be requested when a requested driveline torque is increased or when a driver releases a brake pedal. A transmission upshift may be requested, for example, in response to the vehicle speed and a driveline torque request. In one example, a transmission shift schedule is determined empirically and stored in memory to be indexed by the vehicle speed and the driveline torque request. If the procedure 1700 determines that a transmission upshift and an engine start are required, the procedure goes 1700 to 1704 further. Otherwise, the procedure goes 1700 continue to the end.

at 1704 assess the procedure 1700 whether the DISG is available or not. The procedure 1700 can judge whether the DISG is available or not based on a DISG state flag stored in the memory. Alternatively, the method 1700 based on operating conditions such. B. a battery state of charge, whether a DISG is available or not. For example, if the SOC is less than a threshold level, the DISG may not be available. In another example, the DISG may not be available if the DISG temperature is greater than a threshold. If the procedure 1700 judged that the DISG is available, the answer is yes and the procedure 1700 go to 1712 further. Otherwise, the answer is no and the procedure 1700 go to 1706 further.

at 1706 solve the procedure 1700 a disengaging clutch at a scheduled rate. The disengaging clutch is a lower gear during an upshift. For example, the disengaging clutch triggers a 2nd gear clutch during an upshift from 2nd to 3rd gear. The clutch release rate may be empirically determined and stored in memory such that when the upshift occurs, the disengaging clutch may be released at a rate stored in memory. The disengaging clutch can be released by lowering the oil pressure supplied to the disengaging clutch. The procedure 1700 go to 1708 continue after the disengaging clutch is released.

at 1708 the procedure begins 1700 to apply the engaging clutch after a predetermined amount of time since the disengagement of the disengaging clutch started, to engage a higher gear. The engaging clutch may be applied by increasing the pressure of the oil supplied to the engaging clutch. The predetermined amount of time may be determined empirically and stored in memory for use during an upshift. In one example, the engaging clutch is applied at a time that reduces the possibility of wear of the disengaging clutch by accelerating the output side of the disengaging clutch. The procedure 1700 go to 1710 after the application of the engaging clutch is initiated.

at 1710 applies the procedure 1700 the driveline disconnect clutch or begins to close at a controlled rate to reduce the transmission input shaft torque. In particular, the engine applies a load to the input side of the torque converter by closing the driveline disconnect clutch to reduce the speed of the torque converter impeller speed. In this way, the amount of torque transmitted through the torque converter to the transmission input shaft is reduced. In one example, the driveline disconnect clutch rate is adjusted based on the torque converter impeller speed when the driveline disconnect clutch is applied. The driveline disconnect clutch application pressure is increased, for example, until the torque converter impeller speed is reduced to a threshold amount, and then the driveline disconnect clutch application pressure is not further increased. Since the driveline disconnect clutch transmits torque from the input side of the transmission to the engine, the amount of torque transmitted from the transmission to the engine is limited based on the impeller speed. The procedure 1700 go to 1722 after the driveline disconnect clutch application pressure is increased and the driveline disconnect clutch is at least partially closed.

at 1712 solve the procedure 1700 a disengaging clutch at a scheduled rate. Release of the disengaging clutch allows a higher gear to be applied without torque being transmitted through two different gears. The release rate of the disengaging clutch may be determined empirically and stored in memory for retrieval during upshifting. The procedure 1700 go to 1714 continue after the release of the disengaging clutch is initiated.

at 1714 increases the procedure 1700 the DISG output torque to increase the torque delivered to the torque converter impeller. In one example, the DISG torque is increased by an amount of torque used to accelerate the engine to a desired engine speed. The DISG torque can be increased by increasing an amount of power supplied to the DISG. In other examples, the DISG output torque may be reduced to a lower transmission input torque. The procedure 1700 go to 1716 continue after the DISG torque is increased.

at 1716 the procedure begins 1700 after a predetermined amount of time since the release of the disengaging clutch has begun to apply the on-coming clutch to engage a higher gear. The engaging clutch may be applied by increasing the pressure of the oil supplied to the engaging clutch. The predetermined amount of time may be determined empirically and stored in memory for use during an upshift. In one example, the engaging clutch is applied at a time that reduces the possibility of wear of the disengaging clutch by accelerating the output side of the disengaging clutch. The procedure 1700 go to 1718 after the application of the engaging clutch is initiated.

at 1718 applies the procedure 1700 disconnects or begins closing the driveline disconnect clutch at a controlled rate to reduce transmission input torque and accelerate the engine to a desired cranking speed. In particular, the engine applies a load to the input side of the torque converter by closing the driveline disconnect clutch to reduce the speed of the torque converter impeller. The driveline disconnect clutch application pressure may be modulated to control torque transfer via the driveline disconnect clutch. Further, the driveline disconnect clutch may be applied at any time during the inertia phase of shifting when the engaging clutch is closed.

In one example, the driveline disconnect clutch application rate may be adjusted based on the torque converter impeller speed when the driveline disconnect clutch is being applied. Since the driveline disconnect clutch transfers torque from the input side of the transmission to the engine, the amount of torque transferred to the engine is limited based on the impeller speed. In another example, a transfer function of the driveline disconnect clutch, which relates the transmitted torque based on the amount of input torque provided to the driveline disconnect clutch and the driveline disconnect clutch application pressure, is multiplied by the DISG torque to obtain an amount of torque, which is transmitted to the engine to start the engine to determine. The driveline disconnect clutch application rate may be adjusted to provide a desired cranking torque via the DISG and the driveline disconnect clutch to the engine.

In yet another example, the driveline disconnect clutch application rate may be controlled based on the speed of the DISG and a desired engine speed startup rate. For example, a driveline disconnect clutch application rate may be retrieved from an empirically determined table that outputs the driveline disconnect application rate when indexed about the DISG speed and desired engine acceleration. The procedure 1700 go to 1720 after the driveline disconnect clutch application is initiated.

at 1720 puts the procedure 1700 the DISG torque to provide a desired transmission input torque via the torque converter impeller during or after the inertia phase of the transmission upshift. If the engine mass is relatively high, the DISG output can be increased so that the transmission input torque is not reduced any more than is desired. When the engine mass is relatively low, the DISG torque may be reduced such that the transmission input torque is reduced by a desired amount. The DISG torque can be adjusted by increasing or decreasing the current supplied to the DISG. The procedure 1700 go to 1722 continue after the DISG torque is set.

at 1722 starts the procedure 1700 the engine, when the engine speed reaches a threshold speed, by supplying fuel and a spark to the engine. In some examples, a starter other than the DISG may be engaged with the engine to provide torque to the engine in addition to the torque provided by the driveline disconnect clutch when the engine is started, such that a desired engine cranking speed is achieved can. The procedure 1700 Continue to the end after the engine has started.

In this way, the transmission output shaft torque can be reduced during an inertia phase of shifting, so that driveline torque disturbances can be reduced. Starting the engine via the closure of the driveline disconnect clutch reduces the transmission input shaft torque such that the transmission output shaft torque may be reduced during the inertia phase of the shift.

Regarding 18 FIG. 10 is an example sequence for starting an engine during a transmission gear shift according to the method of FIG 17 shown. The sequence of 18 can through the system of 1 - 3 to be provided. The dashed curves are equivalent to the solid curves when the dashed curves are not visible.

The first diagram from the top of 18 represents the transmission input shaft torque as a function of time. The torque at the transmission input shaft is equal to the transmission torque converter turbine torque. The Y axis represents the transmission input shaft torque and the transmission input shaft torque increases in the direction of the Y axis. The X-axis represents the time and the time increases from the left side of the figure to the right side of the figure. The solid curve 1802 represents the transmission input shaft torque without starting the engine via closing the driveline disconnect clutch or providing transmission input torque reduction. The dotted curve 1804 represents the transmission input shaft torque when starting the engine via the closing of the driveline disconnect clutch and shifting to a higher gear.

The second diagram from the top of 18 represents the transmission output shaft torque as a function of time. The Y axis represents the transmission output shaft torque and the transmission output shaft torque increases in the direction of the Y axis arrow. The X-axis represents the time and the time increases from the left side of the figure to the right side of the figure. The solid curve 1806 represents the transmission output shaft torque without starting the engine via closing the driveline disconnect clutch or providing transmission input torque reduction. The dotted curve 1808 represents the transmission output shaft torque when starting the engine via the closing of the driveline disconnect clutch and shifting to a higher gear.

The third diagram from the top of 18 illustrates the driveline disconnect clutch state as a function of time. The Y axis represents the driveline disconnect clutch state where the driveline disconnect clutch is open near the X axis and closed near the top of the Y axis. The amount of torque transmitted by the driveline disconnect clutch increases as the driveline disconnect clutch is closed. The X-axis represents the time and the time increases from the left side of the figure to the right side of the figure.

The fourth diagram from the top of 18 represents the engine speed as a function of time. The Y-axis represents the engine speed and the engine speed increases in the direction of the Y-axis arrow. The X-axis represents the time and the time increases from the left side of the figure to the right side of the figure.

The fifth diagram from the top of 18 represents the DISG torque as a function of time. The Y axis represents the DISG torque and the DISG torque increases in the direction of the Y axis arrow. The X-axis represents the time and the time increases from the left side of the figure to the right side of the figure.

At time T ₂₇ , the transmission does not switch and the engine is stopped. The DISG outputs torque to the driveline and the transmission input shaft and transmission output shaft torques are constant.

At time T ₂₈ , in response to a transmission shift schedule, the transmission begins to shift the desired driveline torque (not shown) and vehicle speed (not shown). Shifting begins by releasing a disengaging clutch. For example, during an upshift from 2nd gear to 3rd gear, the 2nd gear clutch (disengaging clutch) releases before the 3rd gear (clutch engaged) is applied. The transmission input shaft torque is kept constant, although in some examples it may be increased to better maintain transmission output shaft torque. The transmission output torque begins to decrease in response to disengagement of the disengaging clutch. The driveline disconnect clutch is shown open and the engine is stopped. The DISG torque is shown held at a constant value.

At time T ₂₉ , the inertia phase begins by applying the engaging clutch in response to disengagement of the disengaging clutch. The driveline disconnect clutch begins to close when the on-coming clutch is applied and begins to close. The transmission input shaft torque is also shown decreasing in response to the driveline disconnect clutch closing, as some DISG torque is transmitted via the driveline disconnect clutch to rotate the engine. Engine speed begins to increase in response to the driveline torque being applied to the engine. The DISG torque is shown at a constant level.

Between the time t ₂₉ and the time T ₃₀ of the drive train clutch state is shown modulated to control the amount of drive train torque is applied to the engine. The driveline disconnect clutch application pressure may be modulated in response to engine speed and / or transmission output shaft speed to reduce driveline torque disturbances during shifting and engine starting. Spark and fuel (not shown) are also supplied to the engine so that the engine speed approaches the DISG speed. The transmission output shaft torque gradually increases when the driveline disconnect clutch is applied to restart the engine as indicated by the dashed line 1808 specified. If the driveline disconnect clutch is not applied during the inertia phase, the transmission output shaft torque increases in response to the gear ratio change. Thus, applying the driveline disconnect clutch during inertia phase may reduce driveline torque disturbances.

At time T _30, the inertia phase of the gear shift is completed when the engaging clutch (not shown) is fully applied, as indicated by the fact that the transmission output torque converges to a constant value. The DISG torque is also increasingly shown in response to the completion of the shift, so that the vehicle acceleration can continue.

In this way, driveline torque disturbance during shifting can be reduced. Further, the energy in the driveline may be used to start the engine so that the DISG may provide less torque to start the engine.

The methods and systems of 1 - 3 and 17 - 18 provide shifting of a transmission, comprising: coupling an engine to a transmission in response to a request to upshift the transmission. In this way, the transmission input shaft torque may be reduced to control the transmission output shaft torque during a shift. The method includes where the engine is not coupled to the transmission prior to the gearshift request, the transmission is in a traveling vehicle and in a forward drive, and the vehicle is moving and the transmission is in a higher gear is switched up. The method includes where the engine is coupled to the transmission via the driveline disconnect clutch disposed in a driveline between the engine and a torque converter.

In some examples, the method includes that the engine is coupled to the transmission during an inertia phase of the upshift. The method includes where the engine is coupled to the transmission after the release of a disengaging clutch is initiated during the upshift. The method further includes starting the engine when the engine speed reaches a threshold speed. The method includes where the transmission is an automatic transmission and the input torque to the automatic transmission is reduced during the upshift.

The methods and systems of 1 - 3 and 17 - 18 also provide shifting of a transmission, comprising: reducing input torque to a transmission in response to a transmission upshift request via selectively coupling an engine to an input shaft of the transmission, wherein the engine is not coupled to the transmission prior to the transmission upshift request. The method includes where the engine is coupled to the transmission via a driveline disconnect clutch. The method further includes a torque converter in a driveline disposed between the engine and the transmission. The method further includes increasing or decreasing the torque of a driveline integrated starter / generator during the upshift. The method includes increasing torque from the driveline integrated starter / generator to maintain a torque converter impeller speed greater than a threshold speed. The method includes where the engine rotation is stopped before the transmission upshift request.

The methods and systems of 1 - 3 and 17 - 18 also provide a hybrid vehicle system comprising: an engine; a dual mass flywheel having a first side mechanically coupled to the engine; a driveline disconnect clutch having a first side mechanically coupled to a second side of the dual mass flywheel; a driveline integrated starter / generator (DISG) having a first side coupled to a second side of the driveline disconnect clutch and a second side; a transmission coupled to the DISG; and a controller having nonvolatile instructions executable to initiate a transmission shift request and to couple the engine to the transmission in response to the transmission shift request.

In some examples, the hybrid vehicle system further includes a torque converter disposed in a driveline between the transmission and the DISG. The hybrid vehicle system further includes additional instructions for starting the engine. The hybrid vehicle system further includes additional instructions for coupling the engine to the transmission via the driveline disconnect clutch. The hybrid vehicle system further includes additional commands for increasing the DISG torque in response to the transmission upshift request. The hybrid vehicle system further includes additional commands to decrease the DISG torque in response to the transmission upshift request. The hybrid vehicle system further includes additional instructions for accelerating the engine to a desired cranking speed.

Regarding 19 For example, a method of improving the vehicle driveline response when the driveline includes a dual mass flywheel is shown. The procedure of 19 can be used as executable commands in nonvolatile memory in 1 - 3 shown control unit 12 be saved.

at 1902 determines the procedure 1900 Operating conditions. The operating conditions may include, but are not limited to, engine speed, DMF input and output speeds, requested driveline torque, DISG torque, driveline disconnect clutch state, and engine torque. The procedure 1900 go to 1904 continue after the operating conditions are determined.

at 1904 determines the procedure 1900 the speed and / or position of the upstream or engine side of the DMF. In alternative examples, the torque on the upstream side of the DMF may be determined. The speed and / or position may be determined by a position sensor. The torque can be determined via a torque sensor. The procedure 1900 go to 1906 after the rotational speed and / or position of the upstream side of the DMF are determined.

at 1906 determines the procedure 1900 the speed and / or position downstream or on the driveline disconnect clutch side of the DMF. Alternatively, the torque on the downstream side of the DMF may be determined. The speed and / or position on the downstream side of the DMF can be determined via a position sensor. The torque on the downstream side of the DMF can be determined via a torque sensor. The procedure 1900 go to 1908 after determining the speed and / or position of the DMF on the downstream side.

at 1908 determines the procedure 1900 a speed, position or torque difference between the upstream side of the DMF and the downstream side of the DMF. In one example, the driveline disconnect clutch side of the DMF is one side of the DMF at desired speed and / or position. The speed and / or position of the engine side of the DMF is subtracted from the speed and / or position of the engine side of the DMF to provide a DMF speed and / or position error across the DMF. Alternatively, the torque on the engine side of the DMF may be subtracted from the torque on the upstream side of the DMF to provide a torque error. In some examples, a difference in speed / position between a first side of the DMF and a second side of the DMF during driveline operation is compared to a first side position of the DMF and a second side position of the DMF when torque is not transmitted across the DMF becomes.

In another example, a fast Fourier transform of the DMF upstream and downstream Downstream speed signals are performed to determine the amplitude or magnitude and frequency of any speed oscillations on the upstream and downstream sides of the DMF. The procedure 1900 go to 1910 after the speed error above the DMF and / or the frequencies and amplitudes of the speed upstream and downstream of the DMF are determined.

at 1910 assess the procedure 1900 whether the speed and / or position error or the amplitudes and frequencies on the upstream and downstream sides of the DMF are greater than threshold levels. If so, the procedure goes 1900 to 1912 further. Otherwise, the procedure goes 1900 continue to the end.

at 1912 assess the procedure 1900 whether driveline operating conditions are within a first operating window or not. For example, if the upstream and downstream DMF speed error is greater than a first threshold level. In other examples, the torque difference or position difference across the DMF may be the basis for determining whether or not the driveline operating conditions are within a first operating window. In still other examples, the frequencies or frequency amplitudes are compared to thresholds. If the driveline operating conditions are within a first operating window, the method goes 1900 to 1914 further. Otherwise, the procedure goes 1900 to 1916 further.

at 1914 modulates the process 1900 the transmission torque converter clutch (TCC) to dampen speed and / or torque oscillations across the DMF. The TCC is modulated by changing a duty cycle of a TCC command signal. In other examples, the frequency of the TCC is adjusted. The duty cycle of the TCC command is reduced to increase the slip across the torque converter clutch, thereby increasing the damping of the DMF. However, if the TCC drags a threshold amount when the speed / position difference is detected across the DMF, the TCC may be commanded to increase to a locked position by increasing the TCC duty cycle command. The amount of TCC setting may be based on an error between the desired value and an actual value. For example, the TCC duty cycle may be set based on a difference between the upstream and downstream DMF speeds. The procedure 1900 Continue to the end after the TCC is set.

at 1916 assess the procedure 1900 whether driveline operating conditions within a second operating window are not. For example, if the upstream and downstream DMF speed error is greater than a second threshold level. If the driveline operating conditions are within a second operating window, the method goes 1900 to 1918 further. Otherwise, the procedure goes 1900 to 1920 further.

at 1918 puts the procedure 1900 slippage of the driveline disconnect clutch to adjust damping over the DMF. In one example, the amount of slip over the driveline disconnect clutch is increased to increase damping over the DMF. However, if the driveline disconnect clutch is dragging a threshold amount when the speed / position error is detected, the driveline disconnect clutch is fully closed to stiffen the driveline. The driveline disconnect clutch application force or the driveline disconnect clutch application pressure may be determined based on a difference between the upstream and downstream DMF rotational speeds or differences between desired and actual values of the previously discussed variables such as engine torque. B. the driveline frequency amplitude can be adjusted. The procedure 1900 proceeds to the end after the driveline disconnect clutch application force or driveline disconnect clutch application pressure is set. The procedure 1900 continues to the end after the driveline disconnect clutch is set.

at 1920 assess the procedure 1900 whether driveline conditions are within a third operating window or not. For example, if the upstream and downstream DMF speed error is greater than a third threshold level. If so, the procedure goes 1900 to 1922 further. Otherwise, the procedure goes 1900 to 1924 further.

at 1922 puts the procedure 1900 the torque of the DISG to compensate for the speed / position or torque difference across the DMF. In one example, the output torque of the DISG is increased when the engine side engine speed of the DMF is greater than the engine train disconnect clutch side speed of the DMF. The output torque from the DISG is reduced when the engine side DMF speed is less than the DMF engine driveline disconnect side speed. In one example, the error of DMF speed, DMF position, or DMF torque is input to a function or table that outputs a current need for adjusting DISG torque. Further, the DISG torque is increased when the sign of the error signal is negative. The DISG torque is reduced when the sign of the error signal is positive. When an unwanted frequency or amplitude is determined For example, the torque applied to the DISG may be adjusted to be 180 degrees out of phase with the speed signal error to dampen the undesired speed oscillations. The procedure 1900 continues to the end after the DISG torque is adjusted.

at 1924 increases the procedure 1900 the rate of application of the driveline disconnect clutch when the driveline disconnect clutch is not closed. The driveline disconnect clutch may be closed and application pressure increased by increasing a duty cycle of the driveline disconnect control signal. The procedure 1900 continues to the end after the driveline disconnect clutch is closed.

In other examples, slip of the driveline disconnect clutch, TCC, and DISG torque may be adjusted simultaneously to adjust damping over the DMF. In this way, the process can 1900 Adjust one or more actuators to increase damping or stiffen a driveline when a difference or error in speed / position, frequency, or torque over a DMF is greater than a threshold level.

Regarding 20 FIG. 10 is an example sequence for compensating for a DMF in a driveline according to the method of FIG 19 shown. The sequence of 20 can through the system of 1 - 3 to be provided.

The first diagram from the top of 20 represents the vehicle speed as a function of time. The y-axis represents the vehicle speed and the vehicle speed increases in the direction of the y-axis. The X-axis represents the time and the time increases from the left side of the figure to the right side of the figure.

The second diagram from the top of 20 represents the driveline disconnect clutch application force as a function of time. The Y axis represents the driveline disconnect clutch force and the driveline disconnect clutch application force increases in the direction of the Y axis arrow. The X-axis represents the time and the time increases from the left side of the figure to the right side of the figure.

The third diagram from the top of 20 represents the DMF speed as a function of time. The Y axis represents the DMF speed and the DMF speed increases in the direction of the Y axis arrow. The X-axis represents the time and the time increases from the left side of the figure to the right side of the figure.

The fourth diagram from the top of 20 represents the TCC application force as a function of time. The Y axis represents the TCC application force and the TCC application force increases in the direction of the Y axis arrow. The X-axis represents the time and the time increases from the left side of the figure to the right side of the figure.

The fifth diagram from the top of 20 represents the DISG torque as a function of time. The Y axis represents the DISG torque and the DISG torque increases in the direction of the Y axis arrow. The X-axis represents the time and the time increases from the left side of the figure to the right side of the figure.

At time _T31 , the vehicle speed is increased and the driveline disconnect clutch is fully applied, indicated by the driveline disconnect clutch application force being at the elevated level. The DMF speed is also at a higher level and the TCC clutch is closed, as indicated by the TCC application force being at the elevated level. The DISG torque is also at a higher level, indicating that the DISG provides torque to the vehicle powertrain.

At time T ₃₂ , the vehicle speed reaches zero and the driveline disconnect clutch is opened in response to a low driveline torque request (not shown) to allow the engine to stop. The DMF speed is also reduced to zero as the engine speed goes to zero. The TCC application force is reduced so that there is slip over the torque converter. The DISG torque is also reduced, but the DISG continues to provide torque to the driveline so that the oil pressure in the transmission can be maintained. In other words, the DISG torque is transmitted through the torque converter while the vehicle and the engine are stopped. The DISG torque turns the transmission oil pump to maintain the transmission oil pressure.

At time T ₃₃ , the DISG torque increases in response to an increasing request torque requested by the driver (not shown). The vehicle speed begins to increase in response to the increased DISG torque and the driveline disconnect clutch begins to close in response to the increasing demand torque. The DMF speed increases as the driveline disconnect clutch application force increases to close the driveline disconnect clutch. The actual DMF speed starts to swing and an error between the desired DMF speed and the actual DMF speed or between the desired driveline oscillation amplitude and the actual driveline vibration increases to a level which is greater than a first threshold value. The TCC application force is further reduced to reduce DMF oscillations and / or speed error.

Between time T ₃₃ and time T ₃₄ , the engine and the DISG provide torque to the vehicle driveline. Further, the driveline disconnect clutch remains fully closed and the DMF speed varies as engine speed varies.

At time T ₃₄ , the vehicle speed reaches zero and the driveline disconnect clutch is opened to allow the engine to stop in response to a low driveline torque request (not shown). The DMF speed is also reduced to zero as the engine speed goes to zero. The TCC application force is reduced again so that there is slip over the torque converter. The DISG torque is also reduced.

At time T ₃₅ , the DISG torque increases in response to an increasing request torque requested by the driver (not shown). The vehicle speed begins to increase in response to the increased DISG torque and the driveline disconnect clutch begins to close in response to the increasing demand torque. The DMF speed increases as the driveline disconnect clutch application force increases to close the driveline disconnect clutch. The actual DMF speed starts oscillating at a greater amplitude than at time T ₃₃ and an error between the desired DMF speed and the actual DMF speed or between the desired driveline oscillation amplitude and the actual driveline vibration increases to a level greater than a second threshold. The driveline disconnect clutch application force is reduced to reduce the DMF oscillations and / or speed error.

Between time T ₃₅ and time T ₃₆ , the engine and the DISG provide torque to the vehicle driveline. Further, the driveline disconnect clutch remains fully closed and the DMF speed varies as engine speed varies.

At time T ₃₆ , the vehicle speed reaches zero and the driveline disconnect clutch is opened in response to a low driveline torque request (not shown) to allow the engine to stop. The DMF speed is also reduced to zero as the engine speed goes to zero. The TCC application force is reduced again so that there is slip over the torque converter. The DISG torque is also reduced.

At time T ₃₇ , the DISG torque increases in response to an increasing request torque requested by the driver (not shown). The vehicle speed begins to increase in response to the increased DISG torque and the driveline disconnect clutch begins to close in response to the increasing demand torque. The DMF speed increases as the driveline disconnect clutch application force increases to close the driveline disconnect clutch. The actual DMF speed starts oscillating at a greater amplitude than at time T ₃₅ and an error between the desired DMF speed and the actual DMF speed or between the desired driveline oscillation amplitude and the actual driveline vibration increases to a level greater than a third threshold. The DISG output torque is adjusted (eg, modulated) to dampen the DMF speed, frequency, or torque errors. In addition, the rate of application of the increasing driveline disconnect clutch application force may be increased to stiffen the driveline.

In this manner, various actuators may be adjusted to control driveline torque disturbances that may be present on a DMF. The various actuators may be adjusted according to the disturbance (eg, speed error, torque error, vibration) measured at the DMF.

The methods and systems of 1 - 3 and 19 - 20 provide adjusting operation of a hybrid vehicle driveline, comprising: adjusting an actuator in response to a speed or torque differential across a dual mass flywheel (DMF) disposed in the hybrid vehicle driveline between an engine and a driveline disconnect clutch, the DMF being a driveline component disposed between the engine and the driveline disconnect clutch. In this way, driveline NVH can be reduced.

In one example, the method includes where the actuator is a torque converter clutch. The method includes where the actuator is a driveline integrated starter / generator. The method includes where the actuator is a driveline disconnect clutch. The method includes where the speed difference is above the DMF of an engine position sensor and a position sensor disposed in the hybrid vehicle driveline between the DMF and a driveline disconnect clutch. The method includes where the driveline disconnect clutch is disposed in the hybrid vehicle driveline between the DMF and a driveline integrated starter / generator. The method includes where the driveline disconnect clutch selectively disengages the engine from a driveline integrated starter / generator and a transmission.

The methods and systems of 1 - 3 and 19 - 20 also provide for adjusting the operation of a hybrid vehicle driveline, comprising: engaging a driveline disconnect clutch to rotate an engine via an electric machine; and adjusting an actuator in response to a dual mass flywheel (DMF) speed or torque difference disposed in the hybrid vehicle driveline between the engine and a driveline disconnect clutch, the DMF being a driveline component between the engine and the driveline disconnect clutch. The method includes where the electric machine is a driveline integrated starter / generator (DISG) disposed in the hybrid vehicle driveline at a location between the driveline disconnect clutch and a transmission. The method includes where the actuator is the DISG. The method includes where the DMF transmits engine torque to an automatic transmission or dual countershaft dual clutch transmission. The method includes where the actuator is a different actuator for different conditions. The method includes where a frequency component of an engine speed signal is a base for adjusting the actuator. The method comprises determining the frequency component via a fast Fourier transform (FFT).

The methods and systems of 1 - 3 and 19 - 20 to provide a hybrid vehicle system comprising: an engine; a dual mass flywheel (DMF) having a first side mechanically coupled to the engine; a driveline disconnect clutch having a first side mechanically coupled to a second side of the dual mass flywheel; a driveline integrated starter / generator (DISG) having a first side coupled to a second side of the driveline disconnect clutch; and a controller having nonvolatile instructions executable to adjust an actuator in response to a difference across the DMF.

In one example, the hybrid vehicle system further includes a transmission coupled to a second side of the DISG. The hybrid vehicle system includes where the difference is a position difference between a first side of the DMF and a second side of the DMF compared to a position of the first side of the DMF and a position of the second side of the DMF when no torque is transmitted across the DMF. The hybrid vehicle system includes that the actuator is the DISG. The hybrid vehicle system further includes additional executable instructions for increasing slip over the driveline disconnect clutch when a difference in rotational speed between the first side and the second side of the DMF exceeds a threshold speed. The hybrid vehicle system further includes additional executable instructions to increase the slip across a torque converter clutch when a difference in rotational speed between the first side and the second side of the DMF exceeds a threshold speed.

The methods and systems of 1 - 3 and 19 - 20 also provide for adjusting the operation of a vehicle driveline, comprising: adjusting an actuator in response to the engagement of a driveline disconnect clutch to dampen the vibration of a dual mass flywheel (DMF) disposed between an engine and the driveline disconnect clutch, and the DMF is interposed between the engine Engine and the driveline disconnect clutch is arranged.

Regarding 21 For example, there is shown a method for suppressing driveline torque interference with respect to the application of a driveline disconnect clutch and its transfer function. The procedure of 21 can be used as executable commands in nonvolatile memory in 1 - 3 shown control unit 12 be saved.

at 2102 determines the procedure 2100 Operating conditions. The operating conditions may include engine speed, DMF input and output speeds, requested driveline torque, DISG torque, DISG speed, driveline disconnect clutch state, engine speed, torque converter impeller speed, torque converter turbine speed, and engine torque but not limited to this. The procedure 2100 go to 2104 continue after the operating conditions are determined.

at 2104 assess the procedure 2100 whether a driveline disconnect clutch is open or not. A driveline disconnect clutch may be determined to be open based on a variable stored in memory or based on a difference between the engine speed and the DISG speed. If the procedure 2100 judged that the driveline disconnect clutch is not open, the answer is no and the method 2100 goes to the end further. If the procedure 2100 judges that the driveline disconnect clutch is open, the answer is Yes and the method 2100 go to 2106 further.

at 2106 assess the procedure 2100 Whether an engine start is requested via the DISG or whether or not an engine torque should be applied to the driveline. An engine start may be requested if the requested driveline torque is greater than a threshold torque. Also, there may be a request to provide engine torque to the driveline when the requested driveline torque is greater than a threshold torque. If the procedure 2100 is judged that an engine start is requested via the DISG, or if an engine torque is to be applied to the driveline, the answer is Yes and the method 2100 go to 2108 further. Otherwise, the answer is no and the procedure 2100 continue to the end.

at 2108 assess the procedure 2100 Whether a torque sensor in the vehicle driveline to the in 1 - 3 is present or not. If it is judged that there is a torque sensor, the answer is Yes and the method 2100 go to 2110 further. Otherwise, the answer is no and the procedure 2100 go to 2130 further.

at 2110 determines the procedure 2100 a difference between a desired driveline input torque and an actual driveline input torque at a selected location along the driveline. In some examples, the selected location for the driveline input torque may be at a torque converter impeller, a location between a driveline disconnect clutch and a DISG, at a transmission output shaft, at a torque converter turbine, at a launch input, or at another driveline location. The actual or measured driveline input torque at the selected driveline location is determined by a torque sensor. The desired driveline input torque may be determined by an accelerator pedal position or other source. The difference in torque is the desired driveline input torque minus the actual driveline input torque.

Alternatively, when the torque sensor is disposed in the driveline between the DISG and the driveline disconnect clutch, the torque measured by a torque sensor may be added to a DISG torque command such that the DISG outputs additional torque to start the engine such that the desired transmission input torque is delivered to the gearbox. The procedure 2100 go to 2112 further.

at 2112 puts the procedure 2100 the current supplied to the DISG so that the desired driveline input torque is supplied to the driveline at a fixed location even if the driveline disconnect clutch transfer function is degraded. When the driveline torque sensor is used to return the driveline input torque, the DISG torque is increased if the actual driveline input torque is less than the desired driveline input torque. The DISG torque is reduced when the actual driveline input torque is greater than the desired driveline input torque. In this manner, the DISG torque is adjusted in response to a difference between the desired driveline input torque and the actual or measured driveline input torque.

When the driveline torque sensor is implemented as a positive feedback sensor, the torque sensor output is combined with the desired DISG torque to provide the desired DISG torque at the transmission input or at another predetermined driveline location. In this way, a torque sensor can be used as a feedback or positive feedback device. The procedure 2100 go to 2114 continue after the DISG torque is set.

at 2114 increases the procedure 2100 the driveline disconnect clutch pressure to close the driveline disconnect clutch so that the engine can be started by the DISG or driveline. The driveline disconnect clutch pressure is adjusted by indexing a function that outputs a driveline disconnect command or driveline disconnect application force based on a desired torque for transmission by the driveline disconnect clutch. A spark and fuel can also be at 2114 are supplied after the engine is at a predetermined speed or in a predetermined position. The procedure 2100 go to 2118 after the driveline disconnect clutch pressure starts to increase.

at 2116 assess the procedure 2100 whether the engine started or not. In one example, it may be judged that the engine has started when the engine speed exceeds a threshold speed. If the procedure 2100 judged that the engine has started, the answer is yes and the procedure 2100 go to 2118 further. Otherwise, the answer is no and the procedure 2100 returns 2110 back.

at 2118 assess the procedure 2100 whether the engine speed has accelerated to and equal to the DISG speed or not. The engine rotation speed can be judged to be equal to the DISC speed when an engine speed sensor and a speed sensor DISG substantially the same speed reading (z. B. ± 20 min ^-1). If the procedure 2100 If the engine speed is judged equal to the DISG speed, the answer is Yes and the method 2100 go to 2122 further. Otherwise, the answer is no and the procedure 2100 go to 2120 further.

at 2120 puts the procedure 2100 set the engine speed to the DISG speed. The engine speed may be adjusted to the DISG speed via adjusting engine torque via a throttle and fuel injection. Further, the engine speed may be adjusted by fully closing the driveline disconnect clutch to achieve the DISG speed. However, fully closing the driveline disconnect clutch before engine speed meets DISG may increase driveline torque disturbances. The procedure 2100 returns 2118 back after the engine is set to match the DISG speed.

at 2122 locks the procedure 2100 the driveline disconnect clutch. The driveline disconnect clutch may be locked to the driveline disconnect clutch by supplying more than a threshold amount of pressure. The procedure 2100 continues to the end after the driveline disconnect clutch is locked.

at 2130 opens the procedure 2100 the torque converter clutch (TCC). The torque converter clutch is opened so that the torque on the torque converter impeller can be estimated based on torque converter operating conditions. Alternatively, the torque converter turbine torque may be estimated, if desired. The procedure 2100 go to 2132 continue after the TCC is open.

at 2132 performs the procedure 2100 transition the DISG from a torque control mode to a speed control mode such that the DISG follows a desired speed. The DISG follows the desired speed by performing torque adjustments on the DISG based on a difference between the desired DISG speed and the actual DISG speed. Consequently, the DISG speed is controlled by adjusting the DISG torque in response to the actual or measured DISG speed. In addition, the process appreciates 2100 an amount of torque that provides the driveline disconnect clutch for starting the engine. The desired amount of torque for starting the engine may be determined empirically and stored in memory as a transfer function. The desired amount of torque for starting the engine may be transmitted to the engine via the driveline disconnect clutch by indexing a function that describes the driveline disconnect clutch transfer function. The function outputs a driveline disconnect clutch actuation command that provides the desired driveline disconnect clutch torque. The function is indexed via the desired driveline disconnect torque. The procedure 2100 go to 2134 after the DISG enters the torque control mode from the torque control mode to the speed control mode, and determines an amount of torque for supplying to the engine via the driveline disconnect clutch, so that the engine can be started.

at 2134 orders the procedure 2100 the DISG to a desired speed that is a function of the torque converter turbine speed and the desired torque converter impeller torque to achieve a desired torque converter impeller torque. The desired torque converter impeller torque may be determined by an accelerator pedal input or a controller (eg, desired driveline torque). The desired DISG speed is determined by indexing one or more functions describing the operation of a torque converter (eg, see 45 - 47 ). In particular, a ratio of torque converter turbine speed to torque converter impeller speed is multiplied by a torque converter capacity factor (eg, a torque converter transfer function). The result is then multiplied by the torque converter impeller speed squared to provide the torque converter impeller torque.

Thus, when the torque converter capacity factor, the torque converter impeller torque, and the torque converter turbine speed are known, the torque converter impeller speed that provides the torque converter impeller torque may be determined. In this way, the torque converter transfer function is the basis for providing a desired torque converter impeller torque when no driveline torque sensor is provided. The DISG is set to the torque converter impeller speed which may provide the desired torque converter impeller torque even if the driveline disconnect clutch application force that provides a desired engine cranking torque is incorrect. In addition, the amount of torque that is determined to be applied by the driveline disconnect clutch may be included 2132 are added to the DISG torque command which provides the desired DISG speed in the speed control mode. In this manner, torque transmitted from the DISG to the engine via the driveline disconnect clutch may be added to the DISG torque command such that the DISG achieves the desired torque converter impeller speed and desired torque converter impeller torque even when the driveline disconnect clutch is being applied. The procedure 2100 go to 2136 continue after the DISG speed is set.

at 2136 increases the procedure 2100 the driveline disconnect clutch pressure to close the driveline disconnect clutch so that the engine can be started by the DISG or driveline. The driveline disconnect clutch pressure is closed to provide the desired amount of torque to start the engine, as at 2132 certainly. The driveline spark and fuel can also be used at 2136 are supplied after the engine is at a predetermined speed or in a predetermined position. The procedure 2100 go to 2138 after the driveline disconnect clutch pressure starts to increase.

at 2138 assess the procedure 2100 whether the engine started or not. In one example, it may be judged that the engine has started when the engine speed exceeds a threshold speed. If the procedure 2100 judged that the engine has started, the answer is yes and the procedure 2100 go to 2140 further. Otherwise, the answer is no and the procedure 2100 returns 2132 back.

at 2140 assess the procedure 2100 whether the engine speed has accelerated to the DISG speed and is equal or not. The engine rotation speed can be judged to be equal to the DISC speed when an engine speed sensor and a speed sensor DISG substantially the same speed reading (z. B. ± 20 min ^-1). If the procedure 2100 judges that the engine speed is equal to the DISG speed, the answer is Yes and the method 2100 go to 2144 further. Otherwise, the answer is no and the procedure 2100 go to 2142 further.

at 2142 puts the procedure 2100 set the engine speed to the DISG speed. The engine speed may be adjusted to the DISG speed via adjusting engine torque via a throttle and fuel injection. Further, the engine speed for achieving the DISG speed may be adjusted by fully closing the driveline disconnect clutch. However, fully closing the driveline disconnect clutch before engine speed meets DISG may increase driveline torque disturbances. The procedure 2100 returns 2140 back after the engine is set to adjust to the DISG speed.

at 2144 locks the procedure 2100 the driveline disconnect clutch. The driveline disconnect clutch may be locked to the driveline disconnect clutch by supplying more than a threshold amount of pressure. The procedure 2100 continues to the end after the driveline disconnect clutch is locked.

In this way, the torque converter transfer function may be a basis for estimating and providing the desired torque converter impeller torque when there is no driveline torque sensor and when the driveline disconnect clutch torque transfer function is degraded. On the other hand, if a driveline torque sensor is available, the torque sensor output may be a basis for adjusting the DISG torque such that a desired torque converter impeller torque may be provided even if the driveline disconnect clutch torque transfer function is degraded.

Regarding 22 FIG. 10 is an example sequence for compensating for a driveline disconnect clutch transfer function according to the method of FIG 21 shown. The sequence of 22 can through the system of 1 - 3 to be provided.

The first diagram from the top of 22 represents the base DISG torque request as a function of time. The base DISG request, in one example, is a DISG torque provided to the driveline without feedback from a powertrain torque sensor or feedback of torque converter operating conditions. The Y axis represents the base DISG torque and the base DISG torque increases in the direction of the Y axis. The X-axis represents the time and the time increases from the left side of the figure to the right side of the figure.

The second diagram from the top of 22 represents the torque converter impeller torque as a function of time. The Y axis represents the torque converter impeller torque and the torque converter impeller torque increases in the direction of the Y axis arrow. The X-axis represents the time and the time increases from the left side of the figure to the right side of the figure. The solid curve 2202 represents the desired torque converter impeller torque. The dashed curve 2204 The actual torque converter impeller torque equals the desired torque converter impeller torque when only the desired torque converter impeller torque is visible.

The third diagram from the top of 22 represents the driveline disconnect clutch force as a function of time. The y-axis represents the driveline disconnect clutch force and the driveline disconnect clutch force increases in the direction of the y-axis arrow. The driveline disconnect clutch is closed at higher force and open at lower power. The X-axis represents the time and the time increases from the left side of the figure to the right side of the figure.

The fourth diagram from the top of 22 represents a DISG torque setting as a function of time. Increasing the torque setting increases the DISG torque. The Y axis represents the DISG adjustment torque, and the DISG adjustment torque increases in the direction of the Y axis arrow. The X-axis represents the time and the time increases from the left side of the figure to the right side of the figure.

The fifth diagram from the top of 22 represents the engine speed as a function of time. The Y-axis represents the engine speed and the engine speed increases in the direction of the Y-axis arrow. The X-axis represents the time and the time increases from the left side of the figure to the right side of the figure.

At time T ₃₈ , the DISG torque is at a higher level as is the torque converter impeller torque. The driveline disconnect clutch is closed and there is no DISG torque adjustment because the actual torque converter impeller torque corresponds to the desired torque converter impeller torque. The engine speed is at an elevated level to indicate that the engine is operating.

At time T ₃₉ , the base DISG torque is reduced to zero; however, in some examples, the base DISG torque may be greater than zero to provide a transmission oil pressure. The engine is stopped and the torque converter impeller torque is also reduced to zero. The driveline disconnect clutch is opened so that the engine decouples from the DISG. Between time T ₃₉ and time T ₄₀ , the engine and DISG remain off.

At time T ₄₀ , the base DISG torque increases in response to increasing driver demand torque (not shown) and in response to the driveline disconnect clutch force that may be converted to an amount of torque transferred through the driveline disconnect clutch to the engine. The engine is also rotated in response to the driver request torque so that it is started. The engine is rotated by increasing the driveline disconnect clutch application force in response to the driver demand torque so that the torque may be transferred from the DISG to the engine rotation. The DISG torque transmitted to the engine is estimated based on the driveline disconnect clutch force. In particular, an empirically determined transfer function indexed by the driveline disconnect clutch force outputs a driveline disconnect clutch torque. The commanded DISG torque is the sum of the driveline disconnect clutch torque and the driver request torque. In one example, the driver demand torque is a desired torque converter impeller torque. When the driveline disconnect clutch torque is overestimated or underestimated, the actual torque converter impeller torque deviates from the desired torque converter impeller torque.

In this example, the actual torque converter impeller torque is less than the desired torque converter impeller torque because the driveline disconnect clutch force is increased. As a result, the driveline disconnect clutch torque has been underestimated and less torque is being supplied from the DISG to the torque converter impeller. As a result, the DISG torque is increased to correct the difference between the desired torque converter impeller torque and the actual torque converter impeller torque. The DISG torque boost is shown in the DISG torque adjustment diagram added to the base DISG torque request, shown in the first diagram, and output to the DISG. In In some examples, the estimated driveline disconnect clutch transfer function is further adjusted in response to the DISG torque adjustment. For example, if the DISG torque is increased by 2 Nm, the driveline disconnect clutch transfer function is adjusted to reflect that the driveline disconnect clutch transmits an additional 2 Nm at the current driveline disconnect application force.

The actual torque converter impeller torque may be determined via a torque sensor or, alternatively, torque converter impeller speed, torque converter turbine speed, and torque converter capacity factor, as appropriate 21 and 45 - 47 described. The desired torque converter impeller torque may be determined from an accelerator pedal position or a controller request.

At time T ₄₁ , the engine is started and the engine has accelerated to the same speed as the DISG. Further, the driveline disconnect clutch is closed in response to the engine speed corresponding to the DISG speed. The DISG torque setting is reduced in response to the actual torque converter impeller torque being substantially equal (eg, ± 10 Nm) to the desired torque converter impeller torque after the driveline disconnect clutch is closed.

Consequently, the methods and systems of 1 - 3 and 21 - 22 operating a hybrid vehicle driveline, comprising: opening a torque converter clutch in response to an engine start request; and adjusting a speed of a driveline integrated starter / generator (DISG) in response to a desired torque converter impeller speed. Compensation for a driveline disconnect clutch may be provided in this manner. The method includes where adjusting the DISG speed comprises adjusting the DISG speed as a function of the torque converter turbine speed and the desired torque converter impeller torque. The method includes where the desired torque converter impeller torque is based on driver demand torque. The method includes where the DISG speed is adjusted by adjusting a DISG torque.

In some examples, the method further includes adjusting the DISG torque in response to an estimated driveline disconnect clutch torque. The method includes where the estimated driveline disconnect clutch torque is based on a driveline disconnect clutch application force. The method further includes operating the DISG in a speed control mode when the DISG speed is adjusted.

The methods and systems of 1 - 3 and 21 - 22 provide operating a hybrid vehicle powertrain, comprising: opening a torque converter clutch in response to an engine start request; Operating a driveline integrated starter / generator (DISG) in a speed control mode; Adjusting the DISG speed in response to a desired torque converter impeller speed; and starting an engine via closing the driveline disconnect clutch. The method includes partially closing the driveline disconnect clutch in response to a driveline disconnect clutch application force, and estimating driveline disconnect clutch torque based on a driveline disconnect clutch application force.

In some examples, the method includes adjusting the DISG torque in response to the estimated driveline disconnect clutch torque. The method further includes adjusting the DISG speed in response to a desired torque converter impeller torque. The method includes where the DISG speed is adjusted simultaneously with the closing of the driveline disconnect clutch. The method further includes adjusting a driveline disconnect clutch transfer function in response to a DISG adjustment torque output during closing of the driveline disconnect clutch. The method includes where starting the engine via closing the driveline disconnect clutch includes partially disconnecting the driveline disconnect clutch and then fully closing the driveline disconnect clutch such that the driveline disconnect clutch input speed corresponds to the driveline disconnect output speed when the engine speed is substantially equal to the DISG speed.

The methods and systems of 1 - 3 and 21 - 22 to provide a hybrid vehicle powertrain system comprising: a torque converter; a driveline integrated starter / generator (DISG); an engine; a driveline disconnect clutch disposed in a driveline between the engine and the DISG; and a controller having executable nonvolatile instructions for operating the DISG in a speed control mode and providing a desired torque converter impeller torque via setting the DISG speed in response to a torque converter mode. Turbine wheel speed and the desired torque converter impeller torque.

In some examples, the hybrid vehicle driveline system further includes additional executable nonvolatile instructions for closing the driveline disconnect clutch at a first time that the engine speed is substantially equal to the DISG speed after an engine stall. The hybrid vehicle driveline system further includes additional executable nonvolatile commands for closing the driveline disconnect clutch in response to a request to start the engine. The hybrid vehicle driveline system further includes additional executable nonvolatile instructions for estimating driveline disconnect clutch torque based on a driveline disconnect clutch application force. The hybrid vehicle driveline system further includes a DISG speed sensor and a torque converter turbine speed sensor for determining torque converter turbine speed. The hybrid vehicle driveline system includes where the speed control mode includes adjusting the DISG torque to adjust the DISG speed.

The methods and systems of 1 - 3 and 21 - 22 provide operating a hybrid vehicle powertrain, comprising: adjusting an output torque of a driveline integrated starter / generator (DISG) in response to a difference between a desired driveline torque and an actual driveline torque during at least partially closing a driveline disconnect clutch. In this manner, a desired torque may be provided even if the driveline disconnect torque estimate includes an error. The method includes where the desired driveline torque is a desired torque converter impeller torque and the actual driveline torque is an actual torque converter impeller torque.

In one example, the method includes where the desired driveline torque is based on driver demand torque. The method further includes adjusting an output torque of the DISG based on an estimate of the open loop disconnect clutch torque. The method includes estimating the driveline disconnect clutch torque in an open loop based on a driveline disconnect application command. The method further includes starting an engine via closing the driveline disconnect clutch. The method further includes starting the engine via supplying fuel and spark to the engine before the driveline disconnect clutch is fully closed.

The methods and systems of 1 - 3 and 21 - 22 provide operating a hybrid vehicle powertrain, comprising: adjusting an output torque of a driveline integrated starter / generator (DISG) in response to a difference between a desired driveline torque and an actual driveline torque during at least partially closing a driveline disconnect clutch; and adjusting a driveline disconnect clutch transfer function based on the difference between the desired driveline torque and the actual driveline torque. The method includes where the transfer function describes a driveline disconnect clutch torque as a function of the driveline disconnect clutch application force.

In some examples, the method further comprises starting an engine via at least partially closing the driveline disconnect clutch. The method further comprises starting the engine via supplying a spark and fuel to the engine prior to fully closing the driveline disconnect clutch. The method further includes completely closing the driveline disconnect clutch in response to the engine speed being substantially equal to the DISG speed at a first time since the engine stall. The method includes where the desired driveline torque is based on an accelerator pedal input. The method includes where the actual driveline torque is based on an output of a torque sensor.

The methods and systems of 1 - 3 and 21 - 22 provide a hybrid vehicle powertrain system comprising: a driveline torque sensor; a driveline integrated starter / generator (DISG); an engine; a driveline disconnect clutch disposed in a driveline between the engine and the DISG; and a controller having executable nonvolatile instructions for adjusting the DISG output torque in response to a difference between a desired driveline torque and an output of the driveline torque sensor during application of the driveline disconnect clutch. The hybrid vehicle driveline system further includes additional executable nonvolatile instructions for closing the driveline disconnect clutch at a first time that the engine speed is substantially equal to the DISG speed after an engine start.

In some examples, the hybrid vehicle driveline system further includes additional executable nonvolatile commands to close the driveline disconnect clutch in response to a request to start the engine. The hybrid vehicle driveline system further includes additional executable nonvolatile instructions for adjusting a driveline disconnect clutch transfer function in response to the difference between the desired driveline torque and the output of the driveline torque sensor. The hybrid vehicle driveline system includes where the driveline torque sensor is disposed between a torque converter impeller and the DISG. The hybrid vehicle driveline system includes where the driveline torque sensor is disposed between a torque converter turbine wheel and a transmission gear set.

Regarding 23 FIG. 12 is a flowchart of a method for improving engine restart after stopping combustion in an engine. FIG. The procedure of 23 can as executable instructions in a non-volatile memory of the control unit 12 in 1 - 3 be saved.

at 2302 determines the procedure 2300 Operating conditions. The operating conditions may include, but are not limited to, engine speed, engine position, driveline disconnect condition, DISG speed, and ambient temperature. The procedure 2300 go to 2304 continue after the operating conditions are determined.

at 2304 assess the procedure 2300 Whether there are conditions for automatically stopping the rotation of the engine or not. In one example, engine rotation may stop when the desired driveline torque is less than a threshold. In another example, engine rotation may be stopped when the vehicle speed is less than a threshold speed and when the engine torque is less than a threshold torque. If the procedure 2300 judged that there are conditions for automatically stopping the engine rotation, the method goes 2300 to 2306 further. Otherwise, the procedure goes 2300 continue to the end.

at 2306 terminate the procedure 2300 sequentially injecting fuel into the engine cylinders so that the combustion of fuel in the engine cylinders is not stopped midway during the injection of fuel into a particular cylinder. The procedure 2300 go to 2308 after the fuel injection is finished.

at 2308 assess the procedure 2300 whether the engine speed is below an upper threshold speed for noise, vibration and roughness (NVH) and above a lower NVH threshold speed. If so, the answer is yes and the procedure 2300 go to 2310 further. Otherwise, the answer is no and the procedure 2300 returns 2330 back.

at 2310 assess the procedure 2300 Whether or not the engine crankshaft angle is at a predetermined location when the engine is rotating. In one example, the predetermined position is a crankshaft angle within a predetermined number of crankshaft degrees after a particular cylinder rotates through the compression stroke at top dead center (eg, within 90 crankshaft degrees after the compression stroke at top dead center of a four-cylinder cylinder. combustion engine). If the procedure 2300 judged that the engine crankshaft angle is not at a predetermined location, the answer is no and the method 2300 returns 2308 back. Otherwise, the answer is yes and the procedure 2300 go to 2312 further.

at 2312 orders the procedure 2300 the starter, the starter pinion shaft and the starter pinion with the engine flywheel ring gear engaged. The starter pinion shaft can be moved by a solenoid and the starter pinion can begin to rotate when the pinion shaft is fully extended. In other examples, the starter pinion shaft and the starter pinion ring gear may be separately controlled to enable independent activation. The procedure 2300 go to 2314 after the starter pinion shaft and the starter pinion are commanded to be engaged with the engine.

at 2314 assess the procedure 2300 whether the pinion shaft and pinion are fully engaged with the engine flywheel. In one example, it may be determined via sensor outputs (eg, a limit switch) or via the starter current that the pinion shaft and pinion have engaged the engine. If the procedure 2300 judges that the pinion shaft and the pinion have engaged with the engine, the answer is Yes and the method 2300 go to 2316 further. Otherwise, the answer is no and the procedure 2300 go to 2322 further.

at 2316 puts the procedure 2300 the engine throttle on the basis of the pinion shaft and the pinion, which are engaged with the engine flywheel on a second Position in preparation for a possible driver's sense change with respect to stopping the engine. In one example, the second throttle position is more open than a first throttle position 2322 , The engine throttle position is adjusted to a more open position to provide higher engine torque when driver change occurs after take-off. The engine torque may be affected when the pinion engages the flywheel. Adjusting the engine airflow may compensate for the effect an engaged pinion may have on engine restart and engine deceleration. The procedure 2300 go to 2318 after the engine throttle position is adjusted.

at 2318 assess the procedure 2300 Whether or not a driver change has occurred since the engagement of the starter pinion shaft and the starter pinion has been commanded. A driver's change of mind indicates that the driver wants to continue applying torque to the vehicle wheels to maintain or increase vehicle speed. In one example, a driver's interior change may be indicated by releasing a brake pedal or increasing an engine torque command via an accelerator pedal. If the procedure 2300 judged that a driver change of mind is required before the engine rotation stops, the answer is yes and the procedure 2300 go to 2320 further. Otherwise, the answer is no and the procedure 2300 returns 2308 back.

at 2320 leaves the procedure 2300 The engine over the starter and restarts the engine, since the starter pinion shaft and the pinion have come into engagement with the engine flywheel. Fuel and spark are also in turn supplied to the engine cylinders to facilitate combustion in the engine cylinders. The procedure 2300 ends after the engine has started and restarted.

at 2322 puts the procedure 2300 the engine throttle valve to a first position based on the pinion shaft and the pinion not engaged with the engine flywheel. In one example, the first throttle position is more closed than a second throttle position 2316 , The engine throttle position is adjusted to a more closed position to reduce engine airflow and reduce oxidation within an exhaust system catalyst. The procedure 2300 returns 2308 back after the engine throttle position is set to the first position.

at 2330 assess the procedure 2300 whether the engine speed is lower than the lower NVH speed threshold and whether or not the engine speed is above an intervention speed threshold. The engagement speed is an engine speed at which the engine can rotate in a reverse direction while the engine is stopped. If the engine speed is above the engagement speed and below the lower NVH speed threshold, the answer is Yes and the method 2300 go to 2332 further. Otherwise, the answer is no and the procedure 2300 go to 2350 further. The procedure 2300 also stops attempting to engage the starter at engine speeds below the engagement speed and above the engine speed of zero.

at 2332 orders the procedure 2300 in that the starter pinion shaft and the starter pinion mesh with the engine flywheel ring gear. The starter pinion shaft and the starter pinion may be commanded to engage the engine flywheel ring gear, as in FIG 2312 described. The procedure 2300 go to 2334 after the starter pinion shaft and the starter pinion are commanded to engage the engine flywheel.

at 2334 assess the procedure 2300 whether the pinion shaft and the pinion are engaged with the engine flywheel ring gear or not. The procedure 2300 judges whether the pinion shaft and the pinion mesh with the flywheel ring gear, as in 2314 described. If the procedure 2300 judges that the flywheel is engaged with the pinion and the pinion shaft, the answer is Yes and the method 2300 go to 2336 further. Otherwise, the answer is no and the procedure 2300 go to 2342 further.

at 2336 puts the procedure 2300 the throttle position to a fourth position. Since the engagement of the starter pinion shaft and the starter pinion with the engine flywheel takes place at a lower engine speed, it may be desirable to adjust engine braking via controlling the engine air amount via the throttle to a different degree as compared to when the engagement of the starter pinion shaft and the starter pinion the engine flywheel ring gear is attempted at a higher engine speed. Further, adjusting the amount of engine air can compensate for the engagement of the pinion. In one example, the fourth position is a position in which the throttle is more closed than in the first and second positions 2322 and 2316 , Further, the fourth throttle position is more open than the third throttle position 2342 to focus on one Prepare driver change condition. Adjusting the throttle based on engine speed may also provide finer control of engine position at engine stop. The procedure 2300 go to 2338 continue after the throttle is set to the fourth position.

at 2338 assess the procedure 2300 Whether there is a change of drivers or not. A driver change can be determined as with 2318 described. If the procedure 2300 judged that there is a driver change, the answer is Yes and the method 2300 go to 2340 further. Otherwise, the answer is no and the procedure 2300 returns 2310 back.

at 2340 leaves the procedure 2300 The engine starts and delivers a spark and fuel to the engine. The procedure 2300 can start the engine via the starter or the DISG, as at 2320 described. The procedure 2300 proceeds to the end after the engine has been started and restarted in response to the driver's change.

at 2342 puts the procedure 2300 the throttle valve to a third position. The third position may be a throttle position that is open at the closed position 2336 described fourth position. The third position may also be a throttle position that is more closed than the one at 2322 and 2316 described first and second positions. The procedure 2300 returns 2310 back after the engine throttle position is adjusted.

at 2350 orders the procedure 2300 in that the starter pinion shaft and the starter pinion engage the engine flywheel ring gear after the engine has stopped rotating when disengaged. The engagement of the starter pinion shaft and the starter pinion after the engine stop may reduce the starter and / or ring gear wear. Further, by engaging the starter pinion shaft and the starter pinion before the engine is restarted, it may be possible to shorten the engine starting time. The procedure 2300 go to 2352 after the starter pinion shaft and the starter pinion have been commanded to engage the engine flywheel ring gear.

at 2352 the engine is automatically restarted in response to operating conditions after the engine completes the rotation. The engine may be restarted in response to an engine torque request by a driver or in response to a driver releasing a brake. An automatic engine start occurs when the engine is restarted without a driver operating or operating a device that has a single function to start an engine (eg, a start key switch). An automatic engine start may be initiated by a driver operating or operating a device that has more than one function, such as a device. As a brake pedal that can apply vehicle braking, or secondarily as an indication of when the engine is to start. The procedure 2300 restarts the engine via a starter motor or via the DISG and continues to the end.

In this way, the method of 23 adjust a position of a throttle in response to the starter intervention to further improve the engine restart in the event of a driver's interior change. Furthermore, the method of 23 the throttle position during the engine stop according to the engine speed to improve the engine stop position by limiting the engine backward rotation.

Regarding 24 FIG. 10 is an example sequence for improving the engine restart and the engine after stopping the combustion according to the method of FIG 23 shown. The sequence of 24 can through the system of 1 - 3 to be provided.

The first diagram from the top of 24 represents the engine speed as a function of time. The y-axis represents the engine speed and the engine speed increases in the direction of the y-axis. The X-axis represents the time and the time increases from the left side of the figure to the right side of the figure. The horizontal line 2402 represents an upper NVH engine speed threshold. The horizontal line 2404 represents a lower NVH engine speed threshold. The horizontal line 2406 represents a pinion engagement speed threshold, wherein the pinion is disengaged when the engine speed is below the horizontal line 2406 is, if not the engine has stopped rotating. The engagement threshold may reduce starter degradation.

The second diagram from the top of 24 represents the fuel injection condition as a function of time. The y-axis represents the fuel injection condition. Fuel injection is active when the curve is at a higher level. The fuel injection is stopped when the curve is at a lower level. The X-axis represents the time and the time increases from the left side of the figure to the right side of the figure.

The third diagram from the top of 24 represents the engine throttle position as a function of time. The Y axis represents the engine throttle position and the engine throttle position increases in the direction of the Y axis arrow. The X-axis represents the time and the time increases from the left side of the figure to the right side of the figure.

The fourth diagram from the top of 24 represents the starter pinion state as a function of time. The y-axis represents the starter pinion state and engagement levels are described adjacent to the y-axis. The pinion is returned when the curve is at RET level. The pinion is advanced but not engaged when the curve is at the ADV level. The pinion engages the engine flywheel when the curve is at ENG level. The X-axis represents the time and the time increases from the left side of the figure to the right side of the figure.

The fifth diagram from the top of 24 represents the vehicle brake state (eg, friction brake state) as a function of time. The Y axis represents the vehicle brake state and the brake is applied when the curve is at a higher level. The brake is released when the curve is at a lower level. The X-axis represents the time and the time increases from the left side of the figure to the right side of the figure.

At time T ₄₂ , engine speed is increased, fuel injection is active, the throttle is partially open, the starter is not engaged, and the brake is not applied. These conditions indicate a vehicle traveling at a moderate speed (eg 40 MPH). Between time T ₄₂ and time T ₄₃ , the vehicle brakes are applied to slow the vehicle. Under the illustrated conditions, the vehicle may run between time T ₄₂ and time T ₄₃ or may have stopped.

At time T ₄₃ , the engine combustion is stopped in response to the application of the vehicle brake and a decrease in the throttle position based on the driver request torque. As a result, the engine speed is reduced to be at the upper NVH engine speed threshold 2402 is less than or equal to this. The starter pinion is commanded to engage the engine flywheel, but the pinion only moves forward and does not fully engage the engine flywheel. Throttle position is reduced in response to the engine speed being less than the upper NVH threshold and greater than the lower NVH threshold. Further, the throttle position is adjusted in response to the starter pinion position being advanced but not engaged. The throttle valve is in a first position 2410 open. The engine speed continues to decrease, and the pinion engages the flywheel directly before the time T ₄₄ in engagement. The engine throttle position is moved to a second position in response to the pinion engaging the engine flywheel 2412 set. The second throttle position is more open than the first position. By further opening the throttle valve after the pinion is engaged, it may be possible to prepare for driver change, so that the engine restart can be improved.

At time T ₄₄ , the brake pedal is released by the driver, which is interpreted as a driver's sense change with respect to stopping the engine. The fuel injection is reactivated and the starter provides the engine starting torque via the engaged pinion. The engine reboots and the pinion returns shortly thereafter. Between time T ₄₄ and time T ₄₅ , the engine is accelerated and decelerated over variable driving conditions. The brake is applied again just before time T ₄₅ .

At time T ₄₅ , combustion in the engine is stopped and the engine begins to decelerate. Shortly thereafter, the engine speed will be less than the upper NVH engine speed threshold 2402 reduced. The pinion is advanced in response to the engine speed being less than the upper NVH engine speed threshold and greater than the lower NVH engine speed threshold, but the pinion does not fully engage the engine flywheel. The engine throttle becomes a first position in response to engine speed and pinion condition 2410 set. Engine speed continues to decrease, and the throttle will move to a third position 2414 when the engine speed is less than the lower NVH engine speed threshold 2404 and greater than the intervention threshold 2406 , The third position 2414 is less open than the first position 2410 and the second position 2412 , The pinion engages the engine flywheel while the engine speed is less than the lower NVH engine speed threshold 2404 and greater than the intervention threshold 2406 is. As a result, the throttle valve opens in response to the pinion position and the engine speed set a fourth position. The fourth position 2416 is more open than the third position 2414 , The fourth position may provide additional air to the engine so that the engine can be restarted more easily in the event of a driver's interior change. The engine speed reaches zero without driver change, and the pinion remains engaged.

At time T ₄₆ , the driver releases the brake and the engine is restarted via the meshing pinion in response to the brake being released. The fuel injection is also reactivated in response to the brake being released and a subsequent request to start the engine.

In this way, a position of an engine throttle may be adjusted to improve engine restart while an engine is stopped. Adjusting engine throttle position in response to engine speed and pinion condition during engine stop may help to provide the engine with an amount of air that may improve engine startup. In addition, if the pinion does not engage prior to the engine stall, the adjusted throttle position may improve engine stop by controlling the amount of engine air predictably during engine stop.

The methods and systems of 1 - 3 and 23 - 24 stop stopping the rotation of an engine, comprising: stopping the fuel supply to engine cylinders that burn air and fuel; Commanding engagement of a starter from a non-engine-engaged state into engagement with the engine; and adjusting a position of a throttle valve based on whether the starter is engaged with the engine or not. In this way, the engine can be better prepared to take off when a driver has a change of heart. The method includes where the starter engages the prime mover via a pinion. The method includes where the throttle is adjusted to a first position when the starter is not engaged with the engine within a first engine speed range. The method includes where the throttle is adjusted to a second position when the starter engages the prime mover within the first engine speed range, the second position being more open than the first position.

In some examples, the method further comprises commanding the starter to engage the engine within a predetermined crankshaft angle window. The method includes where the crankshaft angle window is within ± 40 crankshaft degrees of top dead center of a cylinder stroke. The method includes where the engine speed decreases during the command of the engagement of the starter.

The methods and systems of 1 - 3 and 23 - 24 stop stopping the rotation of an engine, comprising: stopping the fuel supply to engine cylinders that burn air and fuel; Commanding the engagement of a starter that is not engaged with the engine to engage the engine; and adjusting a position of a throttle valve based on whether or not the starter engages the engine and the engine speed. The method includes where the throttle position is adjusted to a more closed position at engine speeds less than a threshold speed and a more open position at engine speeds greater than the threshold speed. The method includes where the throttle is adjusted to a first position when the starter is not engaged with the engine within a first engine speed range. The method includes where the throttle is adjusted to a second position when the starter engages the engine within the first engine speed range, the second position being more open than the first position. The method includes where the throttle is adjusted to a third position when the starter does not engage the engine within a second engine speed range. The method includes where the throttle is adjusted to a fourth position when the starter engages the engine within the second engine speed range, the fourth position being more open than the third position.

The methods and systems of 1 - 3 and 23 - 24 to provide a vehicle system comprising: an engine with a throttle; a dual mass flywheel (DMF) having a first side mechanically coupled to the engine; a driveline disconnect clutch having a first side mechanically coupled to a second side of the dual mass flywheel; a starter having a base state in which the starter is not engaged with the engine; a transmission selectively coupled to the engine via the driveline disconnect clutch; and a controller having non-volatile commands executable to adjust a position of the throttle during an engine stop based on whether the starter engages the engine in response to a throttle Engine stop request and before an engine stop.

In some examples, the vehicle system includes adjusting the throttle to a first position in response to the starter not engaging the engine. The vehicle system includes where the throttle is adjusted to a second position in response to the starter engaging the engine, the second position being more open than the first position. The vehicle system further includes additional commands for adjusting throttle position in response to engine speed. The vehicle system further includes additional commands to engage the starter at a predetermined crankshaft location. The vehicle system includes where the predetermined crankshaft location is ± 40 crankshaft degrees from top dead center of a cylinder compression stroke. The vehicle system further includes additional commands to stop the attempt to engage the starter at engine speeds below an engagement speed and above zero engine speed.

Regarding 25 3, a flowchart of a method for adjusting an engine shut-off speed profile and an engine rotation stop position is shown. The procedure of 25 can as executable instructions in a non-volatile memory of the control unit 12 in 1 - 3 be saved.

at 2502 assess the procedure 2500 Whether an engine rotation stop request has occurred or not. An engine rotation stop request may be provided by a control unit or a driver. The controller may automatically stop the engine without the driver providing input from a dedicated actuator having a single function to stop and / or start the engine. For example, an automatic engine stop does not occur when a driver sets an ignition switch to an off state. Alternatively, an automatic engine stop may occur when a driver releases an accelerator pedal. If the procedure 2500 judged that an engine stop is requested, the answer is yes and the procedure 2500 go to 2504 further. Otherwise, the answer is no and the procedure 2500 continue to the end.

at 2504 assess the procedure 2500 Whether the engine rotation should be stopped or not, with the driveline disconnect clutch grinding. The procedure 2500 judges, based on the operating conditions, whether or not the engine should be stopped while the driveline disconnect clutch is dragging. In one example, the engine may be stopped without a driveline disconnect clutch if it is desired to stop the engine in a short amount of time. For example, it may be desirable to quickly stop the engine when the engine speed is relatively low at the time of the engine stop request. On the other hand, the engine may be stopped while the driveline disconnect clutch is dragging when the engine speed is relatively high at the time of the engine stop request. It should also be noted that engine rotation with an open driveline disconnect clutch may be stopped during some conditions. If the procedure 2500 judged that the engine rotation should be stopped with the driveline disconnect clutch grinds, the answer is Yes and the method 2500 go to 2530 further. Otherwise, the answer is no and the procedure 2500 go to 2506 further.

at 2530 determines the procedure 2500 the desired transmission clutch oil line pressure. In one example, the desired transmission clutch oil line pressure may be based on an amount of clutch pressure that keeps a vehicle stopped on a road while the engine has stopped rotating. As a result, the desired transmission clutch oil passage pressure may increase when the vehicle is stopped at a hill. In one example, the desired transmission clutch oil line pressure is determined empirically and stored in a table or function indexed by road grade and vehicle mass. The table outputs the desired transmission clutch oil line pressure in response to road grade and vehicle mass. The procedure 2500 go to 2532 after the desired transmission clutch oil line pressure is determined.

at 2532 turns the procedure 2500 the DISG at a speed that provides the desired transmission clutch oil line pressure by rotating the transmission oil pump. The DISG is coupled to a torque converter impeller and the torque converter impeller is fluidly coupled to the torque converter turbine. The transmission oil pump is driven by the torque converter impeller and the transmission oil pump provides the oil pressure to the transmission clutches when rotated. In one example, the desired transmission oil line pressure indicates a table that empirically includes values of DISG speed that provide the desired transmission clutch oil line pressure. The DISG speed is output from the table and the DISG speed is controlled to the value output from the table. The procedure 2500 go to 2534 continues after the DISG starts rotation at the desired speed.

at 2534 stops the procedure 2500 the fuel flow and the spark to the engine cylinders. The fuel flow to the cylinders can be stopped by closing the fuel injectors. Further, the fuel flow may be stopped in a sequential order based on the engine combustion order so that the cylinders are not partially fueled when commanded that the engine rotation stops. The procedure 2500 go to 2536 after the fuel flow and spark stop to the engine cylinders.

at 2536 leaves the procedure 2500 Grind the driveline disconnect clutch to achieve a desired engine speed curve. In one example, empirically determined driveline disconnect clutch application or slip curves are stored in memory and applied to the driveline disconnect clutch when the engine stop is requested. The slip curve table applies pressure to the driveline disconnect clutch at various rates depending on the engine speed when the engine stop request is made. Alternatively, an empirically determined transfer function that outputs a driveline disconnect clutch application force or a driveline disconnect clutch application pressure based on a desired driveline disconnect clutch pressure that is the basis for operating the driveline disconnect clutch. In addition, the slip curve may include the timing of when the pressure is to be supplied to the driveline disconnect clutch. For example, the pressure may be applied to the driveline disconnect clutch a predetermined number of crankshaft degrees after a final amount of fuel is supplied to an engine cylinder prior to engine stop. As a result, the initial time of the driveline disconnect clutch pressure application and the rate at which the pressure is applied to the driveline disconnect clutch are stored in memory and applied when an engine stop request is issued. The procedure 2500 go to 2538 after the application of the driveline disconnect clutch pressure profile is initiated.

at 2538 orders the procedure 2500 in that the transmission clutches connect the transmission output shaft to the transmission housing. The transmission output shaft may be connected to the transmission by simultaneously applying to the other transmission clutches as the driveline disconnect clutch at the same time as described in U.S. Patent Application No. 12 / 833,788. The procedure 2500 go to 2540 after the transmission is commanded into a connected state.

at 2540 opens the procedure 2500 the driveline disconnect clutch. The driveline clutch can be opened when the engine speed is substantially zero (for. Example, 100 min ^-1 or less) and the combustion engine has stopped in a desired position. Alternatively, the driveline disconnect clutch may be opened when the engine speed falls to a predetermined value. By changing the operation of the driveline disconnect clutch, the method 2500 thus controlling the engine speed curve partially or completely to zero engine speed. The procedure 2500 continues to the end after the driveline disconnect clutch is opened.

at 2506 closes the procedure 2500 the driveline disconnect clutch when the driveline disconnect clutch is not yet closed. The driveline disconnect clutch may be closed by increasing a duty cycle signal that increases the driveline disconnect clutch application pressure. The procedure 2500 go to 2508 after the driveline disconnect clutch is closed.

at 2508 stops the procedure 2500 the fuel flow and the spark to the engine cylinders. The fuel flow and spark can be stopped as in 2534 is described. The procedure 2500 go to 2510 after the fuel and spark supply to the engine cylinders is stopped.

at 2510 puts the procedure 2500 DISG speed and DISG torque to provide a desired engine speed profile during the engine rotation stop. In one example, an empirically determined group of engine speed curves are stored in memory and used as a basis for stopping the engine. For example, if the engine speed is greater than that of the engine speed curve retrieved from memory, the DISG torque absorption is increased to direct the engine speed to the desired engine speed profile. If the engine speed is less than that of the engine speed curve retrieved from the memory, the DISG torque is increased to steer the engine speed to the desired engine speed profile. The engine speed curve table slows down engine speed at various rates depending on engine speed when the engine stop request is made. Additionally, the engine speed curve may include the time at which the engine speed curve is to be controlled via the DISG. The For example, an engine speed curve may be controlled by the DISG for a predetermined number of crankshaft degrees after a final amount of fuel is delivered to an engine cylinder prior to engine stop. Thus, the initial application time of the engine speed profile and the rate of engine speed reduction are stored in memory and controlled by the DISG when an engine stop request is issued. The procedure 2500 go to 2512 after the application of the driveline disconnect clutch pressure profile is initiated.

at 2512 orders the procedure 2500 in that the transmission clutches connect the transmission output shaft to the transmission housing. The transmission output shaft may be connected to the transmission by simultaneously applying to other transmission clutches than the driveline disconnect clutch at the same time as described in U.S. Patent Application No. 12 / 833,788, which is fully incorporated herein by reference. The procedure 2500 go to 2514 after the transmission is commanded into a connected state.

at 2514 opens the procedure 2500 the driveline disconnect clutch at a predetermined engine speed. The driveline disconnect clutch is opened so that the engine may coast to zero speed while the DISG continues to rotate and supply pressure to transmission clutches while the engine is stopped. In one example, the driveline disconnect clutch is opened at a predetermined engine speed based on engine speed at which engine stop was initiated (eg, engine speed at which fuel flow to the engine cylinders is stopped) and the rate of engine speed decay. Further, the driveline disconnect clutch may be opened at a particular crankshaft angle to further control the engine stop position. A table or function indicated by the rate of engine speed drop and engine speed at which the engine stop was requested outputs the engine position at which the driveline disconnect clutch is opened. In one example, the position corresponds to an engine position that improves the possibility of stopping at the desired engine position (eg, during a predetermined crankshaft interval of a cylinder in a compression stroke). The procedure 2500 go to 2516 after the driveline disconnect clutch is opened.

at 2516 determines the procedure 2500 a desired transmission clutch line pressure. The desired transmission clutch line pressure is determined as at 2530 is described. The procedure 2500 go to 2518 after the desired transmission clutch oil line pressure is determined.

at 2518 turns the procedure 2500 the DISG to maintain the desired transmission clutch oil line pressure. The DISG can be rotated as in 2532 is described. The procedure 2500 proceeds to the end after the DISG is commanded to deliver the desired transmission clutch oil line pressure. It should be noted that the DISG may be periodically stopped and restarted to maintain the transmission clutch oil line pressure. If the transmission clutch oil line pressure has a slow leak rate, the DISG may be commanded to turn off. The DISG may be reactivated when the transmission clutch oil line pressure drops to a threshold level.

In this way, the engine stop position for a hybrid vehicle can be controlled. The driveline disconnect clutch may adjust an engine stop profile from idle speed to zero speed via periodically providing torque from the DISG to the engine such that the engine stops at a desired position.

Regarding 26 FIG. 10 is an example sequence for stopping an engine according to the method of FIG 25 shown. The sequence of 26 can through the system of 1 - 3 to be provided.

The first diagram from the top of 26 represents the engine speed as a function of time. The y-axis represents the engine speed and the engine speed increases in the direction of the y-axis. The X-axis represents the time and the time increases from the left side of the figure to the right side of the figure.

The second diagram from the top of 26 represents the DISG speed as a function of time. The Y axis represents the DISG speed and the DISG speed increases in the direction of the Y axis. The X-axis represents the time and time increases from the left side of the figure to the right side of the figure.

The third diagram from the top of 26 The driveline disconnect clutch apply force (eg, the force applied to close the driveline disconnect clutch) is a function of time. The X-axis represents the time and the time increases from the left side of the figure to the right side of the figure.

The fourth diagram from the top of 26 represents the fuel supply state as a function of time. The Y axis represents the fuel supply state and the fuel is supplied to the engine when the curve is at a higher level. The fuel is not supplied to the engine when the curve is at a lower level. The X-axis represents the time and the time increases from the left side of the figure to the right side of the figure.

The fifth diagram from the top of 26 represents the transmission connection state as a function of time. The Y axis represents the transmission connection state and the transmission is connected when the curve is at a higher level. The transmission is not connected when the curve is at a lower level. The X-axis represents the time and the time increases from the left side of the figure to the right side of the figure.

At time T ₄₇ , engine speed and DISG speed are equal and at an elevated level. The engine is mechanically coupled to the DISG via the driveline disconnect clutch. The driveline disconnect clutch is fully closed when the driveline disconnect clutch input speed is equal to the driveline disconnect clutch output speed. Further, the driveline disconnect clutch is fully closed when the driveline disconnect force is at a higher level. Fuel is supplied to the engine as indicated by the fuel supply condition being at a higher level. The transmission is not connected because the transmission connection state is at a lower level.

At time T ₄₈ , the engine is commanded to an off state in response to operating conditions (eg, a low engine torque request and an applied vehicle brake). The fuel supply to the engine is stopped as indicated by the fuel supply state transitioning to a lower level. Additionally, the DISG speed / DISG torque is adjusted to control the engine speed and engine position curve in response to the engine stopping request. In one example, the engine speed / position curve is stored in memory and the DISG torque is adjusted in response to a difference between the actual engine speed and the desired engine speed curve stored in memory. For example, at a specific time after the engine stop request, if the actual engine speed is less than the desired engine speed, the DISG torque is increased to move the actual engine speed to the desired engine speed. In another example, if a particular engine position (eg, compression stroke at top dead center of cylinder number one) is prior to where it is desired at a particular time after requesting engine stop, the negative DISG torque may be increased. to slow the engine at a greater rate.

At time T ₄₉ , the driveline disconnect clutch is opened in response to the engine reaching a predetermined speed. Further, clutches of the transmission begin to be applied so that the transmission output shaft is connected to the transmission housing and the vehicle chassis. By opening the driveline disconnect clutch at a predetermined speed, it may be possible to better control engine speed during engine stalling while allowing the DISG to operate. In this example, the DISG is stopped, but in other examples, it may continue to rotate to provide a motive force to operate the transmission oil pump. The engine and the DISG are stopped shortly after the disconnect clutch is opened.

In this way, an engine may be stopped such that the engine position can be controlled during stoppage. By controlling the engine stop position, it may be possible to improve the engine restart performance consistency.

At time T ₅₀ , the DISG is accelerated and provides torque to the vehicle driveline in response to a driver releasing a brake pedal (not shown). Furthermore, the DISG helps when starting the engine. In particular, the driveline disconnect clutch is partially closed to transfer torque from the DISG to the engine. Fuel and spark are supplied to the engine to assist combustion in the engine as indicated by the fuel delivery condition transitioning to a higher level. Finally, the transmission clutches are also opened in response to the release of the brake to decouple the transmission. The driveline disconnect clutch is fully closed when engine speed reaches DISG speed.

In this way, the engine may be restarted while torque is being supplied to the vehicle driveline to accelerate the vehicle. Furthermore, the Driveline disconnect clutch operated in a manner that can reduce driveline torque disturbances.

Between time T ₅₀ and time T ₅₁ , the engine and DISG provide torque to the vehicle driveline based on a driver request. In this example, the driveline disconnect clutch remains closed; however, it can occasionally open without stopping the engine.

At time T ₅₁ , the engine is commanded to an off state in response to operating conditions (eg, a low engine torque request and an applied vehicle brake). The fuel supply to the engine is stopped as indicated by the fuel supply state transitioning to a lower level. The driveline disconnect clutch is also commanded to lower by reducing the driveline disconnect clutch application force. In one example, the driveline disconnect clutch slip rate is stored in memory as a function of time since the engine stop request. The slip rate may be increased or decreased as the engine speed deviates from a desired engine speed. For example, at a specific time after the engine stop request, when the engine speed is less than a desired engine speed, the driveline disconnect clutch slip may be reduced by increasing the driveline disconnect clutch application force. In this manner, additional torque may be supplied by the DISG to the engine so that the engine speed is adjusted to the desired engine speed. The DISG speed is commanded to a speed that allows the transmission oil pump to provide a desired oil pressure.

At time T ₅₂ , the engine speed reaches a predetermined speed and the transmission clutches are applied to connect the transmission output shaft to the vehicle chassis. The DISG continues to rotate, providing oil pressure to the transmission clutches.

In this manner, a driveline disconnect clutch may grind during an engine stop procedure to provide a desired engine stop position. In some examples, the desired engine stop position is where a particular cylinder piston stops within a predetermined number of degrees before the compression stroke at top dead center of the cylinder.

The methods and systems of 1 - 3 and 25 - 26 to provide an engine stopping method comprising: adjusting a speed of a driveline integrated starter / generator (DISG) to a desired speed that provides a desired transmission clutch oil line pressure in response to a request to stop engine rotation; and grinding a driveline disconnect clutch in a driveline between the DISG and the engine to stop the engine in a desired position. The method includes where the desired position is a predetermined number of crankshaft degrees prior to the compression stroke at top dead center of a selected cylinder. The method further includes stopping the fuel flow and the spark to the engine cylinders in response to the request to stop engine rotation. The method further includes connecting a transmission output shaft to a transmission housing in response to the request to stop engine rotation.

In some examples, the method further comprises opening the driveline disconnect clutch at an engine speed of substantially zero. The method further includes continuing the rotation of the DISG while the engine is at zero speed. The method further includes enabling and disabling the DISG while the engine speed is zero.

The methods and systems of 1 - 3 and 25 - 26 also provide an engine stop method, comprising: closing a driveline disconnect clutch in response to a request to stop engine rotation; Adjusting a speed of a driveline integrated starter / generator (DISG) to a desired engine speed profile that decelerates toward an engine speed of zero; and opening the driveline disconnect clutch at a predetermined engine speed. The method further includes connecting a transmission output shaft to a transmission housing in response to a request to stop the engine. The method further includes stopping the fuel flow and the spark to the engine cylinders in response to the request to stop the engine. The method includes where the driveline disconnect clutch is disposed in a driveline between an engine and the DISG.

In some examples, the method further comprises opening the driveline disconnect clutch in a predetermined position. The method includes where the speed of the DISG is increased when the engine speed is less than the desired engine speed profile. The method includes reducing the speed of the DISG when the engine speed is greater than the desired engine speed profile.

The methods and systems of 1 - 3 and 25 - 26 to provide a vehicle system comprising: an engine; a dual mass flywheel (DMF) having a first side mechanically coupled to the engine; a driveline disconnect clutch having a first side mechanically coupled to a second side of the dual mass flywheel; a driveline integrated starter / generator (DISG) having a first side coupled to a second side of the driveline disconnect clutch; a transmission selectively coupled to the engine via the driveline disconnect clutch; and a controller having executable instructions stored in a nonvolatile memory for adjusting actuation of the driveline disconnect clutch in response to a request to stop engine rotation.

In some examples, the vehicle system includes at least partially closing the driveline disconnect clutch. The vehicle system includes fully closing the driveline disconnect clutch. The vehicle system further includes additional instructions for opening the driveline disconnect clutch at a predetermined engine speed. The vehicle system further includes operating the DISG at a speed that provides a desired transmission clutch oil line pressure. The vehicle system further includes additional instructions for selectively disabling the DISG at zero engine speed.

Regarding 27 FIG. 12 is a method of stopping an engine when a vehicle in which the engine is operating is parked on varying slopes. FIG. The procedure of 27 can as executable instructions in the non-volatile memory of the control unit 12 in 1 - 3 be saved.

at 2702 assess the procedure 2700 Whether a vehicle in which an engine is operated is stopped or not. In one example, it may be determined that the vehicle is stopped when the vehicle speed is zero. If the procedure 2700 judged that the vehicle is stopped, the answer is yes and the method 2700 go to 2704 further. Otherwise, the answer is no and the procedure 2700 continue to the end.

at 2704 assess the procedure 2700 Whether engine stop conditions are met or not. In one example, the engine stop conditions may include, but are not limited to, driver demand torque being less than a threshold torque, engine speed being less than a threshold speed, and using the vehicle brake. In other examples, other engine stop conditions may be used. When engine stall conditions exist, the answer is yes and the method 2700 go to 2706 further. Otherwise, the answer is no and the procedure 2700 continue to the end.

at 2706 appreciates the process 2700 the road gradient and the vehicle mass. In one example, the road grade may be determined via an inclinometer. The vehicle mass can be determined as at 904 from 9 described. In addition, the procedure stops 2700 the engine rotation. The procedure 2700 go to 2708 continue after the vehicle mass and road grade are determined.

at 2708 assess the procedure 2700 whether or not the road inclination is greater than a first threshold road incline. In one example, the first threshold and other threshold road slopes may be a function of vehicle mass. For example, as the vehicle mass increases, the first threshold road slope may decrease. If the procedure 2700 judges that the current road grade is greater than a first threshold road grade, the answer is yes and the method 2700 go to 2716 further. Otherwise, the answer is no and the procedure 2700 go to 2710 further.

at 2710 keeps the procedure 2700 maintains the transmission oil pressure to allow the transmission gearshift and shifts from a lower gear (eg, first gear) to a higher gear (eg, second gear) when the transmission is not yet in second gear. By shifting to a higher gear, the vehicle mass is effectively increased at the vehicle wheels, making it more difficult to move the vehicle. The transmission oil pressure can be maintained by an electric oil pump. The procedure 2700 go to 2712 continue after the transmission is switched.

at 2712 assess the procedure 2700 Whether a vehicle acceleration or an increased torque request is requested or not. In one example, an increased driver demand is determined by an accelerator pedal position. If the procedure 2700 judges that a vehicle acceleration or an increased torque request is requested, the answer is Yes and the method 2700 go to 2714 further. Otherwise, the procedure returns 2700 to 2710 back.

at 2714 increases the procedure 2700 the torque delivered to the driveline and downshifts the transmission to a lower gear (eg, first gear) to accelerate the vehicle. The driveline torque may be increased via the DISG or via the engine after starting the engine. The engine may be started by cranking through the DISG or a starter with lower power output capacity. The procedure 2700 continues to the end after the transmission is in first gear and torque for the driveline is increased.

at 2716 assess the procedure 2700 whether or not the road inclination is greater than a second threshold road incline. If the procedure 2700 judges that the current road grade is greater than a second threshold road grade, the answer is Yes and the method 2700 go to 2724 further. Otherwise, the answer is no and the procedure 2700 go to 2718 further.

at 2718 keeps the procedure 2700 Maintaining the transmission oil pressure to allow transmission gear shifting and shifting to a higher gear than the second gear (eg, 3rd gear) when the transmission is not yet in a higher gear. By shifting to a higher gear than the second gear, the vehicle mass is effectively increased at the vehicle wheels, so that it is more difficult to move the vehicle. The transmission oil pressure can be maintained by an electric oil pump. The procedure 2700 go to 2718 continue after the transmission is downshifted.

at 2720 assess the procedure 2700 Whether a vehicle acceleration or an increased torque request is requested or not. In one example, an increased driver demand is determined by an accelerator pedal position. If the procedure 2700 judges that a vehicle acceleration or an increased torque request is requested, the answer is Yes and the method 2700 go to 2722 further. Otherwise, the procedure returns 2700 to 2718 back.

at 2722 increases the procedure 2700 the torque supplied to the driveline and shifts the transmission down to first gear to accelerate the vehicle. The driveline torque may be increased via the DISG or via the engine after starting the engine. The engine may be started by cranking through the DISG or a starter with a lower power output capacity. The procedure 2700 continues to the end after the transmission is shifted to the first gear and the amount of torque supplied to the driveline is increased.

at 2724 applies the procedure 2700 the vehicle brakes, keeps the transmission oil pressure upright to allow the transmission gear shift, and shifts to the first, if it is not yet in first gear. By shifting to first gear and applying the brakes, the vehicle may be ready for acceleration while stopped on a grade. Further, by not applying the brakes on lower slopes, brake wear can be reduced while vehicle motion is reduced. The transmission oil pressure can be maintained by an electric oil pump. The procedure 2700 go to 2726 continue after the vehicle brakes are applied.

at 2726 assess the procedure 2700 Whether a vehicle acceleration or an increased torque request is requested or not. If the procedure 2700 judges that vehicle acceleration or increased torque request is requested, the answer is Yes and the method 2700 go to 2728 further. Otherwise, the procedure returns 2700 to 2724 back.

at 2728 increases the procedure 2700 the torque supplied to the driveline and releases the vehicle brakes so that the vehicle can accelerate. The driveline torque may be increased via the DISG or via the engine after starting the engine. The engine may be started by cranking through the DISG or a starter with lower power output capacity. The procedure 2700 continues to the end after the vehicle brakes are released.

As described herein, an engine shutdown or engine stop operation, such as, for example, may occur. B. when it comes to a vehicle stop, used to save fuel. During such an operation, the driveline disconnect clutch may be opened. Therefore, when the vehicle is at rest, possibly on a hill climb, the engine is often shut down to rest. An alternative pressure source other than the engine may thus be used to maintain transmission hydraulic pressure while the engine is off. In some examples, an auxiliary electric pump may be used to maintain the transmission hydraulic pressure. In other examples, the DISC speed does not fall to zero when the vehicle is stopped, but is maintained at a low speed, typically well below the idling (z. B. 200-500 min ^-1) to maintain the transmission hydraulic pressure. Under these conditions, the torque converter output torque is either zero (since the input speed is zero) or a value that is not sufficient to prevent the vehicle from rolling backwards when the brake is released. One method uses the wheel brakes to prevent the vehicle from rolling backwards; however, although it is effective in some cases, it may also result in degraded vehicle launch performance or require a tilt sensor.

Another problem may be that, when the driver depresses the brake pedal, one or both of the vehicle brakes and regenerative braking may be applied based on the operating conditions. For example, the brake torque generated by the DISG during regenerative braking (with or without engine shutdown and open driveline disconnect clutch) may be balanced with the friction wheel brake torque to provide a desired deceleration rate that corresponds to the brake pedal pressure. Since, when the vehicle comes to a stop, the regenerative braking torque decreases to perform a roll back prevention function, a greater proportion of the friction braking torque must be "reversed", thus reducing the advantage of regenerative braking. Consequently, alternative rollback protection methods may be desirable to increase the ability to utilize regenerative braking.

In one example, the torque converter based automatic transmission may be equipped with an overrunning clutch. If the transmission fluid pressure is maintained while the vehicle is stationary and the transmission is kept in gear (as opposed to neutral, for example), then the one-way clutch acts as a mechanical rollback device to prevent the vehicle from rolling backwards, when the vehicle is on a hill slope. Depending on the vehicle mass and the angle of inclination, however, holding the transmission in a lower gear, z. B. the first gear, only slow down the vehicle roll when the brake on a steeper slope, z. B. 6%, is solved. In this example, when the transmission is in first gear, the torque, which is a function of the sine of the pitch angle and the vehicle mass, may be sufficient to overcome the one-way clutch holding torque. Thus, in one example, the transmission may be maintained in a gear that is higher than the first gear, if necessary, to prevent the vehicle from rolling backwards at the maximum design pitch. For example, the transmission may be shifted to a higher gear before it comes to a stop to allow the rollback protection, such. On the basis of an estimated slope during vehicle travel.

Over a predetermined inclination, z. 6%, the tilt detection system based on a longitudinal sensor may be used to determine the tilt. Thus, in some examples, the control unit may determine whether the current grade is above an upper limit, and if so, the brake system may be additionally applied to assist the rollback operation to prevent vehicle rollback.

For heavier vehicles or a vehicle that may have higher loads, such as: As a vans, it may be advantageous to apply multiple clutches in the transmission to increase the maximum transmission holding torque. By applying two or more clutches while the vehicle is stationary, the transmission input can be "connected" to the transmission housing. This method may also be used as part of an engine restart vehicle launch technique to shape the transmission output torque when the vehicle is leaving a stop. Therefore, by maintaining the transmission hydraulic pressure while the vehicle is stopped, and applying the clutch (s) to either keep a gear or put the transmission in a connected state, the vehicle can be prevented from rolling backwards when the driver Release the brake.

Regarding 28 FIG. 10 is an example sequence for stopping an engine when a vehicle in which the engine is operating is parked on a slope according to the method of FIG 27 shown. The sequence of 28 can through the system of 1 - 3 to be provided.

The first diagram from the top 28 represents the vehicle speed as a function of time. The y-axis represents the vehicle speed and the vehicle speed increases in the direction of the y-axis. The X-axis represents the time and the time increases from the left side of the figure to the right side of the figure.

The second diagram from the top of 28 represents the road inclination as a function of time. The Y axis represents the road incline and the road incline increases in the direction of the Y axis. The X-axis represents the time and the time increases from the left side of the figure to the right side of the figure. The horizontal line 2802 represents a first swell slope. The horizontal line 2804 represents a second threshold slope that is greater than the first threshold slope.

The third diagram from the top of 28 represents the transmission gear as a function of time. The Y-axis represents the gear and the respective gears are along the Y-axis identified. The X-axis represents the time and the time increases from the left side of the figure to the right side of the figure.

The fourth diagram from the top of 28 represents the engine state as a function of time. The Y axis represents the engine state and the engine operates when the engine state curve is at a higher level. The engine is stopped when the engine state curve is at a lower level. The X-axis represents the time and the time increases from the left side of the figure to the right side of the figure.

The fifth diagram from the top of 28 represents the vehicle brake condition (eg, friction brake condition) as a function of time. The Y-axis represents the vehicle brake condition and the vehicle brake is applied when the brake condition curve is at a higher level. The brake is not applied when the brake state is at a lower level. The X-axis represents the time and the time increases from the left side of the figure to the right side of the figure.

The sixth diagram from the top of 28 represents the vehicle brake pedal condition as a function of time. The y-axis represents the vehicle brake pedal condition and the vehicle brake pedal is applied when the brake pedal condition curve is at a higher level. The brake pedal is not applied when the brake pedal state is at a lower level. The X-axis represents the time and the time increases from the left side of the figure to the right side of the figure.

At time T ₅₃ , the vehicle speed is increased, the road grade is close to zero, and the transmission is in 5th gear, indicating that the vehicle is traveling at high speed. The engine is working and the brake pedal and brakes are not applied.

Between time T ₅₃ and time T _54, the vehicle decelerates in response to a lower driver request torque (not shown) and shifts down from fifth gear to first gear. The vehicle brake is applied as well as the brake pedal. Shortly before time T ₅₄ , the transmission is shifted to 2nd gear in response to the road inclination and an engine stop request after the vehicle is stopped.

At time T ₅₄ , the engine is stopped and the transmission is held in second gear to increase the effective mass of the vehicle as shown on the wheels of the vehicle. The vehicle brake pedal and brakes remain applied; However, in some examples, after the vehicle is stopped, the vehicle brake may be released when the brake pedal is applied after the transmission is shifted to a higher gear. The road grade remains near zero and below the first grade threshold 2802 ,

At time T ₅₅ , the brake pedal is released by a driver. The vehicle brakes are released in response to the brake pedal releasing. The transmission is also downshifted to first gear to improve vehicle acceleration in response to the driver releasing the brake. The engine is also started in response to the driver releasing the brake. The vehicle begins to accelerate a short time after the brake pedal is released in response to increasing driver demand torque.

Between time T ₅₅ and time T ₅₆ , the vehicle accelerates and then decelerates in response to driver demand torque and application of the brake pedal and brakes as indicated by the brake state and the brake pedal state. The transmission also shifts from 1st to 5th gear while the vehicle accelerates and slows down. The road gradient also increases and is greater than the first threshold road gradient 2802 until time T ₅₆ . The brake pedal and brakes are applied by the driver to slow down the vehicle.

At time T ₅₆ , the vehicle stops and the transmission is downshifted to first gear as indicated by the vehicle speed and transmission curves. The engine continues working when the vehicle stops.

At time T ₅₇ , the transmission will respond in response to the vehicle tilt being greater than the first threshold slope 2802 , and upshifted to a request to stop the engine in the 3rd gear. The shifting of the transmission increases the effective mass of the vehicle on the vehicle wheels, making it more difficult to roll down the increased incline. The engine is stopped shortly after the transmission is upshifted. The brake pedal and vehicle brakes remain applied by the driver; However, in some examples, after the vehicle is stopped, the vehicle brake may be released when the brake pedal is applied after the transmission is shifted to a higher gear.

At time T ₅₈ , the driver releases the brake pedal and the brakes are released in response to the brake pedal being released. The Transmission is downshifted from 3rd gear to 1st gear and the engine is started as indicated by the transition of the engine state. The brakes and the engine change state in response to the brake pedal being released. The vehicle begins to accelerate in response to increasing driver demand torque (not shown) shortly after the brake pedal is released.

Between time T ₅₈ and time T ₅₉ , the vehicle accelerates and then decelerates in response to driver demand torque and application of the brake pedal and brakes as indicated by the brake state and the brake pedal state. The transmission also shifts from 1st gear to 5th gear while the vehicle accelerates and decelerates. The road gradient also increases and is greater than the second threshold road gradient 2804 until time T ₅₉ . The brake pedal and brakes are applied by the driver to slow down the vehicle. The vehicle comes to a stop before time T ₅₉ .

At time T ₅₉ , the engine is stopped and the vehicle brakes are in response to the brake pedal, a low driver demand torque and that the road grade is greater than the threshold road grade 2804 , applied. The brake pedal curve and the brake state curve are at higher levels to indicate that both the brakes and the brake pedal are being applied.

At time T ₆₀ , the driver releases the brake pedal and the engine is started in response to the brake pedal being released. The brake state remains at a higher level to indicate that the brakes are being applied. The brakes remain applied in response to the road grade being greater than the second road grade threshold 2804 and the driver request torque is less than a threshold torque (not shown). The vehicle is stationary as indicated by the vehicle speed curve being zero.

At time T ₆₁ , the driver request torque (not shown) increases and the vehicle brake is released in response to the increased driver request torque. The vehicle also begins to accelerate in response to the increased driver demand torque, as indicated by the vehicle speed increasing.

In this manner, the vehicle and driveline may respond to the changing vehicle tilt such that a vehicle remains substantially stationary when the engine is stopped while the vehicle is on a grade. When the vehicle is stopped on increasing inclines, vehicle movement reduction measures are progressively increased.

The methods and systems of 1 - 3 and 27 - 28 to provide a vehicle stop method, comprising: upshifting a transmission into a gear in response to a road slope when a vehicle is stationary; and automatically stopping an engine of the vehicle in response to vehicle conditions. The method includes where the gait number increases as the road grade increases. The method includes where automatically stopping the engine includes stopping the engine in response to a low driver request torque. The method includes where automatically stopping the engine further comprises stopping the engine in response to the vehicle speed. The method includes where automatically stopping the engine includes stopping the engine in response to a vehicle brake pedal condition. The method includes where the transmission is shifted without driver switch request and that the transmission is an automatic transmission. The method further includes downshifting the transmission in response to increasing driver demand torque after the transmission is upshifted.

The methods and systems of 1 - 3 and 27 - 28 also provide a vehicle stop method comprising: during a first condition, upshifting a transmission to a first gear ratio in response to a first road grade when a vehicle is stationary; during a second condition, upshifting the transmission into a second gear ratio in response to a second road grade when the vehicle is stationary; and automatically stopping an engine in response to vehicle conditions. The method includes where the first gear ratio is a lower gear ratio than the second gear ratio, and the gear is not in a first gear when the gear is shifted to the first gear ratio. The method further includes downshifting the transmission in response to increasing driver demand torque after the upshift of the transmission during the first and second conditions.

In some examples, the method includes the second road slope being greater than the first road grade. The method further includes maintaining the transmission oil pressure while the transmission is switched. The method includes where the engine is stopped before the transmission is shifted and the transmission oil pressure is maintained via a driveline integrated starter / generator. The method further comprises selecting the first gear ratio and the second gear ratio in response to the vehicle mass.

The methods and systems of 1 - 3 and 27 - 28 to provide a vehicle system comprising: an engine; a transmission in selective mechanical communication with the engine; and a control unit having executable instructions stored in a non-volatile memory for switching the transmission to a gear in response to a road inclination while a vehicle in which the engine is operating is stationary, the control unit also having instructions for applying the vehicle brakes in response to road inclination. The vehicle system includes stopping the engine before the transmission is shifted and maintaining the transmission oil pressure via a driveline integrated starter / generator. The vehicle system further includes additional instructions for selecting the first gear ratio and the second gear ratio in response to the vehicle mass.

In some examples, the vehicle system further includes additional commands to downshift the transmission in response to increasing driver demand torque after the vehicle is stationary. The vehicle system further includes additional instructions for releasing the vehicle brakes in response to increasing driver demand torque after the vehicle is stationary. The vehicle system includes that the transmission is an automatic transmission.

Regarding 29A and 29B 1 is a flowchart of a method of providing vehicle brakes via the vehicle driveline. The procedure of 29A and 29B can be used as executable instructions in nonvolatile memory in the system of 1 - 3 be saved.

at 2902 determines the procedure 2900 Operating conditions. The operating conditions may include, but are not limited to, vehicle speed, engine speed, brake pedal position, desired driveline torque, DISG speed, and battery state of charge. The procedure 2900 go to 2904 continue after the operating conditions are determined.

at 2904 assess the procedure 2900 whether conditions exist or not, to automatically stop the engine. The engine may be automatically stopped in response to vehicle conditions rather than in response to an input having a single function to start and / or stop engine rotation (eg, an on / off key latch). For example, when a driver turns an engine stop key for the engine, the engine is not automatically stopped. However, when the driver releases an accelerator pedal having a function of providing a driveline torque request, the engine may be automatically stopped in response to a low torque request. If the procedure 2900 judged that there are conditions for automatically stopping the engine, the answer is Yes and the method 2900 go to 2906 further. Otherwise, the answer is no and the procedure 2900 continue to the end.

at 2906 assess the procedure 2900 Whether or not drivetrain brakes are required. Driveline vehicle braking may be requested during vehicle deceleration to reduce the amount of wheel braking used to decelerate the vehicle. For example, driveline braking via an engine or DISG may be provided when a vehicle is traveling down a hill, so a smaller amount of wheel brakes may be used to slow the vehicle. In one example, the method may 2900 assess that driveline braking is requested when the vehicle is accelerating and a low driveline torque request is present. If the procedure 2900 judged that driveline braking is required, the answer is yes and the procedure 2900 go to 2910 further. Otherwise, the answer is no and the procedure 2900 go to 2908 further.

at 2908 provides the procedure 2900 a desired torque to the driveline via the DISG and / or the engine. Positive engine torque may be provided by the engine combusting an air / fuel mixture and rotating the driveline. The DISG can provide torque in response to an amount of current flowing to the DISG. The procedure 2900 continues to the end after the desired torque is delivered to the driveline.

at 2910 assess the procedure 2900 Whether or not the DISG has a capacity to deliver the desired amount of vehicle braking without the engine. In one example, the method assesses 2900 whether or not the DISG has the capacity to provide the desired amount of vehicle brakes without engine braking, in response to Vehicle speed, a selected transmission gear and the DISG torque absorption capacity. In particular, a table describing the empirically determined torque absorption capacity of the DISG is indexed by the DISG speed, as determined from the vehicle speed and the selected gear. If the procedure 2900 judges that the DISG has the capacity to provide the desired amount of driveline braking without the engine providing braking, the answer is yes and the method 2900 go to 2916 further. Otherwise, the answer is no and the procedure 2900 go to 2912 further.

at 2912 turns the procedure 2900 the engine without supplying fuel to the engine and engine rotation losses are increased, so that the driveline braking can be increased. The engine rotation losses may be increased by adjusting the valve timing. In one example, the intake valves are opened near the top dead center intake stroke, and the exhaust valves are opened early in the expansion stroke (eg, prior to 90 crankshaft degrees after the compression stroke at top dead center) to increase engine rotational losses and boost driveline braking. The engine is rotated by closing the driveline disconnect clutch, which couples the engine to the remainder of the driveline, as in FIG 1 - 3 shown. The procedure 2900 go to 2914 after the engine is rotated and engine revolutions are increased.

at 2914 converts the process 2900 the kinetic energy of the vehicle into electrical energy. In particular, the DISG is set in a generator mode in which the rotational energy from the vehicle wheels is converted into electrical energy and stored in a battery or other energy storage device. In one example, the rotational energy provided by the driveline from the vehicle wheels, through the transmission, through the torque converter, and to the DISG is converted to electrical energy, producing current flow through a stator. The electrical energy can then be stored in an energy storage device. The procedure 2900 returns 2906 back after the kinetic energy of the vehicle begins to be converted into electrical energy.

at 2916 assess the procedure 2900 Whether the energy storage device SOC is larger than a threshold charge amount or not. In one example, the SOC may be estimated based on a voltage across the energy storage device. If the procedure 2900 judges that the energy storage device SOC is greater than a threshold amount, the answer is Yes and the method 2900 go to 2930 further. Otherwise, the answer is no and the procedure 2900 go to 2918 further.

In addition, the process can 2900 at 2916 to 2930 go on when a driver requests increased driveline braking. For example, when a driver presses a button to enter a downhill mode, the procedure goes 2900 to 2930 Continue to increase the driveline braking.

at 2918 transfers the procedure 2900 the DISG from the torque control mode to a speed control mode. In the speed control mode, the DISG output torque is adjusted in response to the DISG speed so that the DISG speed converges to a desired DISG speed. In one example, the DISG torque is increased if the DISG speed is less than the actual DISG speed. Likewise, the DISG torque is reduced when the DISG speed is greater than the actual DISG speed. The DISG is operated in a speed control mode so that the DISG can respond to driveline rotational speed changes caused by the torque changes. As a result, the torque converter impeller may rotate at a desired constant speed during driveline disconnect clutch transitions so that torque transmitted through the torque converter is more constant. In this way, the DISG reduces driveline torque disturbances that may be caused by the opening of the driveline disconnect clutch. The procedure 2900 go to 2920 continues after the DISG is set in the speed control mode.

at 2920 stops the procedure 2900 engine rotation by opening or disengaging the driveline disconnect clutch and stopping fuel flow to the engine cylinders. The driveline disconnect clutch may be opened before fuel flow to the engine cylinders is stopped such that the non-combusting engine does not reduce driveline rotational speed and driveline torque at the torque converter impeller. The procedure 2900 go to 2922 after the engine rotation is stopped and the driveline disconnect clutch begins to open.

at 2922 puts the procedure 2900 the torque capacity of the torque converter clutch (TCC) to suppress driveline disconnect clutch opening disturbances. When the driveline mode is changed to the energy regeneration mode and the driveline disconnect clutch begins to open, the current impeller speed may be increased vary as the amount of torque transmitted from the engine to the driveline is changed. In one example, the torque capacity of the TCC is modulated and controlled to provide smooth transitions between the state changes of the driveline disconnect clutch. As such, a more consistent vehicle speed can be maintained when the driveline disconnect clutch is opened. For example, if the torque converter impeller speed begins to decrease as the disconnect clutch opens, the TCC may be adjusted for slip in an increased amount. The procedure 2900 go to 2924 continue after the TCC is set.

at 2924 converts the process 2900 the kinetic energy of the vehicle into electrical energy, as in 2914 described. The electrical energy is directed to an electrical energy conversion storage device where it is held and may be used at a later time. The electric power conversion device may be a battery or a capacitor. The procedure 2900 go to 2926 continues after the conversion of the vehicle's kinetic energy into electrical energy begins.

at 2926 goes the procedure 2900 in a torque control mode after any disturbance has been mitigated by opening the driveline disconnect clutch. The procedure 2900 Also adjusts the DISG to provide negative torque to an extent equal to what the engine delivers during deceleration fuel cutoff.

An amount of braking torque that an engine may provide may be determined empirically and stored in memory. The engine brake amount may include settings for the valve timing, the engine oil temperature, the engine speed, the throttle position, and the air pressure. The adjustments may be added to a base engine braking torque identified at nominal valve timings, a nominal engine temperature, engine speed, throttle position, and a nominal air pressure. The engine braking torque can be determined, for example, at an engine oil temperature of 90 ° C, an engine speed of 1500 min ^-1, a base valve timing, a closed throttle valve and an air pressure of 100 kPa. The engine brake torque may be adjusted from the base brake torque if the operating conditions deviate from the base conditions.

The current engine operating conditions (eg, oil temperature, valve timing, etc.) are determined and are the basis for indexing empirically determined tables and / or functions that output engine braking torque at current operating conditions. Once the engine brake torque is determined under the current operating conditions, the DISG torque is adjusted to engine brake torque. By setting the DISG torque to engine brake torque, it may be possible to transition from providing brake torque using the DISG to provide brake torque across the engine without the DISG providing brake torque when the energy conversion device SOC is greater than a threshold.

The engine conditions may be continuously monitored so that a negative or regeneration DISG torque may be checked as engine operating conditions change. For example, as engine oil temperature decreases and engine friction increases, negative DISG torque, which emulates engine brake torque when fuel flow to the engine is stopped, may be increased to reflect the change in engine brake torque. The procedure 2900 go to 2928 after the negative DISG torque is set to engine brake torque when the engine is rotated without supplying fuel to the engine and when combustion is not occurring in the engine.

at 2928 activates and increases the procedure 2900 automatically selected vehicle electrical loads to increase the amount of time the DISG can continue to provide driveline braking. For example, when the vehicle is traveling down a mountain for an extended period of time, the energy storage device may be fully charged so that it can not accept additional charge. During such conditions, the DISG may stop delivering charge to the energy storage device to reduce the possibility of energy storage device degradation. However, it may be possible for the DISG to continue to provide charge to the energy storage device when additional charge is provided to vehicle systems so that the energy storage device charge does not increase.

In one example, the power supplied to selected electrically powered vehicle systems is increased when the energy storage device state of charge is greater than one Threshold level. In other examples, the power supplied to selected electrically powered vehicle systems is increased when the charge delivered by the DISG to the battery is greater than a threshold charge rate. In some examples, when the energy storage device charge state is greater than a threshold level, the engine is rotated, the DISG ceases to operate in generation mode, and the power provided to selected electrically powered vehicle systems continues until the charge of the energy storage device is increased to a second Threshold level is reduced, and then the DISG returns to the generation mode. The engine stops rotating when the charge of the energy storage device is less than a threshold level.

Selected electric powered vehicle systems can be automatically activated and turned on, or they can be supplied with more power than requested. The selected electrically powered vehicle systems may be, but are not limited to, front and rear window defrosters, exhaust after-treatment heaters, electric pumps, and lights. For example, the front and rear window defrosters may be activated without notifying the driver, so that the driver may not notice that electrical energy is being consumed to prolong the DISG operation in the regeneration mode. The output of an electric pump (eg, a fuel pump) may also be increased by increasing the pump current without the driver noticing. Likewise, emission system heaters and vehicle lights may be activated to prolong DISG operation in the regeneration mode. The procedure 2900 returns 2906 back after the electrical loads are set.

at 2930 increases the procedure 2900 slippage across a torque converter clutch (TCC) when the TCC is locked. As the TCC drags, slip over the TCC continues to increase. The grinding of the TCC reduces torque disturbances that may be introduced into the driveline via connecting and disconnecting the driveline disconnect clutch. In one example, the TCC is included 2934 in a controlled slip mode and the TCC is modulated in response to torque converter impeller speed changes. The procedure 2900 go to 2932 continue after the slip is set above the TCC.

at 2932 sets the procedure 2900 the DISG in the speed control mode after exiting the torque control mode and adjusts the DISC torque to keep the DISG speed to a substantially constant value (eg., ± 50 min ^-1 a commanded DISG speed). In one example, the DISG speed is compared to a desired DISG speed and the current delivered to the DISG is adjusted in response to a difference in the DISG speed and the desired DISG speed. If the DISG speed is less than the desired DISG speed, additional power is supplied to the DISG to increase DISG torque and DISG speed. If the DISG speed is greater than the desired DISG speed, the power supplied to the DISG is decreased to decrease the DISG speed and DISG torque provided to the driveline. Setting the DISG to the speed control mode allows the DISG to control driveline torque without causing driveline speed changes that may be undesirable to a driver. The procedure 2900 go to 2934 continues after the DISG is set in the speed control mode.

at 2934 sets the procedure 2900 TCC capacitance to a constant value or transition to a new control gain value for closed loop TCC slip control. For example, a signal that controls the amount of torque that the TCC transmits via the torque converter is adjusted as the torque converter impeller speed changes to reduce driveline disturbances. In one example, the TCC slip amount is set in accordance with a TCC transfer function that outputs a TCC control signal duty cycle. The TCC transfer function is indexed based on torque converter impeller speed and torque converter turbine speed. The procedure 2900 go to 2936 continue after the TCC capacity is set.

at 2936 assess the procedure 2900 whether there is a starter other than the DISG or not. In some examples, if a starter other than the DISG is unavailable or in a degraded condition, the method may be 2900 judge the non-DISG starter to be non-existent. If the procedure 2900 judged that a starter other than the DISG is not present, the answer is no and the procedure 2900 go to 2950 further. Otherwise, the answer is yes and the procedure 2900 go to 2938 further.

at 2950 closes the procedure 2900 at least partially the driveline disconnect clutch while the DISG is in the speed control mode to rotate the engine. In one example, the drive train clutch is closed in a position that provides a desired engine cranking speed (eg., 250 min ^-1). The desired cranking speed may vary depending on the operating conditions and may in some examples, not lower than the DISG speed. Closing the driveline disconnect clutch causes a driveline torque to be transmitted to the engine. Consequently, the current supplied to the DISG may be increased when the driveline disconnect clutch is engaged to maintain the DISG speed. In this way, the torque transmitted through the torque converter can be maintained at a constant level because the torque converter impeller speed is constant. The procedure 2900 go to 2952 continue after the driveline disconnect clutch is at least partially closed.

at 2952 provides the procedure 2900 a spark and fuel to the engine cylinders to start the engine. In one example, fuel is supplied to the engine cylinders via direct fuel injectors. The procedure 2900 go to 2954 after the spark and fuel are supplied to the engine cylinders.

at 2954 assess the procedure 2900 Whether combustion takes place in the engine cylinders or not. In one example, the method assesses 2900 in that there is combustion in the engine cylinders as the engine output torque increases. An increase in engine speed may indicate combustion in the engine cylinders. In other examples, combustion in the engine cylinders may be determined via cylinder pressure sensors. If the procedure 2900 determines that there is combustion in the engine cylinders, the answer is yes and the method 2900 go to 2956 further. Otherwise, the answer is no and the procedure 2900 returns 2954 back.

at 2956 opens the procedure 2900 the driveline disconnect clutch and adjusts the DISG torque. Opening the driveline disconnect clutch may reduce the amount of torque transferred from the DISG and driveline to start the engine when the driveline disconnect clutch is disengaged before the engine begins to generate more torque to drive the engine to DISG speed to accelerate. Opening the driveline disconnect clutch also reduces the amount of torque delivered by the driveline for accelerating the engine. Therefore, the DISG torque may be reduced to maintain the DISG at a constant speed when the driveline disconnect clutch is released. In examples where the kinetic energy of the vehicle is rotating the DISG, the amount of torque absorbed by the DISG can be adjusted. The procedure 2900 go to 2940 after the driveline disconnect clutch is opened.

at 2938 turns the procedure 2900 the engine over a different starter than the DISG. In one example, the starter has a lower power output capacitance than the DISG and the starter selectively engages a flywheel coupled to an engine crankshaft. The starter provides an engine cranking speed of less than 250 min ^-1. The spark and fuel are also at 2938 delivered to the engine. The procedure 2900 go to 2940 continue after the engine starts to spin.

at 2940 speeds up the process 2900 the engine speed to a speed that is synchronous with the DISG. The engine is accelerated by adjusting the fuel, the spark, and the cylinder air amount for the engine cylinders. The procedure 2900 go to 2942 after the engine speed reaches the DISG speed.

at 2942 keeps the procedure 2900 The engine speed is at the DISG speed and provides a net torque of substantially zero (eg, ± 10 Nm) from the engine crankshaft. In other words, the engine torque is just being set high enough to overcome engine losses and turn the engine at DISG speed. The procedure 2900 go to 2944 after the engine net torque is substantially zero.

at 2944 closes the procedure 2900 the driveline disconnect clutch. Substantially no torque is transmitted between the driveline and the engine when the driveline disconnect clutch is closed, thus providing a smooth transition between disabling the engine and operating the engine. The combustion engine is operated with substantially the DISG speed (z. B. ± 25 min ^-1) when the drive train separating clutch is closed. The procedure 2900 go to 2946 after the driveline disconnect clutch is closed.

at 2946 reduces the procedure 2900 the engine combustion torque (eg, the engine torque provided by combustion) and then the fuel injection is stopped so that the engine does not rotate under its own power. The engine output torque is reduced by reducing cylinder air quantities and cylinder fuel amounts. Further will be Engine revolutions over setting the engine valve timing increased. For example, intake valves of a cylinder may be opened close to the intake stroke at top dead center, and exhaust valves of the cylinder may be opened between the compression stroke at top dead center and 45 crankshaft degrees after the compression stroke at top dead center to increase engine rotation losses. The valves of other cylinders can be operated in a similar manner. Negative torque generated by the DISG during regeneration may be reduced to smooth the transition from the engine providing combustion torque to the engine providing brake torque during fuel cut. Further, the negative DISG torque may be adjusted to maintain a constant torque converter impeller speed as the DISG converts kinetic energy into electrical energy. In this manner, rotating the engine may increase a load applied to the driveline to provide a desired amount of driveline braking for the vehicle. The procedure 2900 go to 2948 after the engine combustion torque is reduced.

In one example, the amount of regenerative torque requested by the DISG should be consistent with the amount of engine braking torque that is currently available, such as 2926 described. The engine braking torque may be estimated based on engine oil temperature, engine friction, and pumping at the current impeller speed. Once the system is in engine braking, the actual engine braking may be compared to the estimated engine braking and a correction may be made to the estimation. In this way, the vehicle may decelerate at the same rate for both engine braking and regenerative braking when the brake pedal is not depressed.

at 2948 keeps the procedure 2900 the DISG torque is substantially constant and returns the TCC to a closed loop slip control. For example, the TCC command signal may be adjusted to provide a desired speed difference between the torque converter impeller and the torque converter turbine. The procedure 2900 returns 2906 after the TCC is returned to a closed loop slip control mode.

In an alternative example, engine rotation may begin and fuel and spark may be withheld from the engine while the engine is cranking up to DISG speed. The driveline disconnect clutch initially closes a small amount and a higher slip level is above the driveline disconnect clutch. The DISG may be transitioned from a generator state to an engine state to reduce any driveline torque disturbance when the acceleration of the engine provides additional negative torque to the driveline. Additional pressure is applied to the driveline disconnect clutch to increase the negative torque delivered by the engine to the driveline. The DISG torque is adjusted while the DISG is in speed control mode to provide the desired level of driveline braking. In one example, the DISG current is adjusted to provide a desired vehicle deceleration rate.

In another example 2936 - 2956 be replaced by a step in which the engine remains at zero rotation while vehicle braking is increased via friction brakes (eg, wheel brakes) without driver input, while the DISG torque absorption (eg, converting mechanical rotational energy into electrical energy) is reduced. The friction braking force can be increased in proportion to the reduction in DISG driveline braking. Consequently, the vehicle brakes are applied automatically while reducing the driveline braking provided by the DISG.

In this way, the method of 29A -B driveline braking, so that fuel can be saved by converting kinetic energy into electrical energy. Further, the method may reduce driveline torque disturbances via controlling the DISG, the TCC, and other driveline components.

Regarding 30 FIG. 10 is an example sequence for providing vehicle brakes via a driveline according to the method of FIG 29A -B shown. The sequence of 30 can through the system of 1 - 3 to be provided.

The first diagram from the top of 30 sets the torque converter turbine speed as The Y-axis represents the torque converter turbine speed and the torque converter turbine speed increases in the direction of the Y-axis arrow. The X-axis represents the time and the time increases from the left side of the figure to the right side of the figure.

The second diagram from the top of 30 represents the engine speed as a function of time. The y-axis represents the engine speed and the engine speed decreases in the direction of the y-axis arrow. The x-axis represents the time and the time decreases from the left side of the figure to the right side of the figure too.

The third diagram from the top of 30 represents the application force of the torque converter clutch (TCC) as a function of time. The Y axis represents the TCC application force and the TCC application force increases in the direction of the Y axis arrow. The X-axis represents the time and the time increases from the left side of the figure to the right side of the figure.

The fourth diagram from the top of 30 represents the driveline disconnect clutch torque as a function of time. The Y-axis represents the driveline disconnect clutch torque and the driveline disconnect clutch torque increases in the direction of the Y-axis arrow. The X-axis represents the time and the time increases from the left side of the figure to the right side of the figure.

The fifth diagram from the top of 30 represents the DISG output torque as a function of time. The Y axis represents the DISG output torque and the DISG output torque increases in the direction of the Y axis arrow. The X-axis represents the time and the time increases from the left side of the figure to the right side of the figure.

The sixth diagram from the top of 30 represents the engine torque as a function of time. The Y-axis represents the engine torque and the engine torque increases in the direction of the Y-axis arrow. The X-axis represents the time and the time increases from the left side of the figure to the right side of the figure.

At time T ₆₂ , the engine is stopped, the turbine speed is increased, and the DISG provides negative torque (eg, brake torque) to the driveline. The TCC clutch is locked and the driveline disconnect clutch is open and does not transmit torque.

At time T ₆₃ , the torque converter clutch slip is increased in response to a request to restart the engine. The request to restart the engine is based on an increase in driver demand torque (not shown). The TCC force decreases as the torque converter clutch slip is increased. The engine speed remains constant, the driveline disconnect clutch remains open and the DISG charges a battery and provides negative driveline torque.

Between time T ₆₃ and time T ₆₄ , the DISG transitions from a torque control mode to a speed control mode in response to the increase in driver demand torque. The DISG is then set to a desired speed. The TCC is also adjusted to provide a constant amount of slippage.

At time T ₆₄ , the driveline disconnect clutch is at least partially closed to start the engine. The DISG torque is increased from negative torque toward zero torque, and then it becomes positive to provide torque to start the engine. The amount of DISG torque increase depends on the amount of torque used to start the engine. The engine speed increases when a spark and fuel are delivered to the engine when the engine is rotating.

Between time T ₆₄ and time T ₆₅ , engine output torque increases and combustion torque accelerates the engine. The DISG is returned to brake mode and the driveline disconnect clutch is opened in response to combustion in the engine. Opening the driveline disconnect clutch allows the engine to accelerate to DISG speed without impacting driveline torque.

At time T ₆₅ , the driveline disconnect clutch is closed in response to engine speed reaching DISG speed. Closing the driveline disconnect clutch after the engine reaches DISG speed may reduce driveline torque disturbances. Engine torque is also reduced by decreasing a throttle opening amount or by adjusting cylinder valve timing.

At time T ₆₆ , the engine is transitioned to a deceleration fuel cutoff mode with the engine rotating without being fueled and without combusting an air / fuel mixture. The engine provides braking torque as it rotates without being fueled. Engine braking torque may be adjusted by adjusting intake manifold pressure via a throttle or cylinder valves. The DISG is also returned to torque control mode.

Consequently, the methods and systems of 1 - 3 and 29 - 30 controlling driveline braking, comprising: providing driveline braking via an electric machine while rotation of an engine is stopped; and starting the rotation of the engine in response to a battery state of charge exceeding a threshold. In this way, engine braking may take over DISG braking when the energy storage device charge is greater than a threshold (eg, fully charged). The method further includes automatically stopping the engine and opening a driveline disconnect clutch between the engine and the electric machine while the engine is stopped, and further comprising providing engine brake torque to wheels after starting the engine rotation, and at least the driveline disconnect clutch partially closed to turn the engine.

In one example, the method further comprises operating the electric machine in a speed control mode while converting the kinetic energy of the vehicle to electrical energy. The method further includes increasing the slip of a torque converter clutch during the start of engine rotation while the engine speed is less than an idle speed of the engine. The method includes where the engine is rotated via a driveline integrated starter / generator. The method includes engaging a driveline disconnect clutch to couple the prime mover with the driveline integrated starter / generator. The method further includes operating the electric machine in a speed control mode and adjusting the torque of the electric machine to maintain driveline speed at a substantially constant torque.

The methods and systems of 1 - 3 and 29 - 30 also provide for controlling driveline braking, comprising: providing driveline braking via a first electric machine while rotation of an engine is stopped; Commencing rotation of the engine in response to a battery state of charge exceeding a threshold, wherein the rotation of the engine is performed via a second electric machine. The method includes where the second electric machine is not coupled to the engine before the engine rotation is commanded. The method includes where the first electric machine is not mechanically coupled to the engine while the engine rotation is stopped.

In one example, the method includes where the second electric machine is released from the engine after the engine speed reaches a threshold speed. The method further includes closing a driveline disconnect clutch when the engine speed is substantially equal to that of the first electric machine. The method further includes increasing torque converter clutch slip during closing of the driveline disconnect clutch. The method includes where a power output capacitance of the second electric machine is lower than a power output capacitance of the first electric machine.

The methods and systems of 1 - 3 and 29 - 30 also provide a vehicle system comprising: an engine; a dual mass flywheel (DMF) having a first side mechanically coupled to the engine; a driveline disconnect clutch having a first side mechanically coupled to a second side of the dual mass flywheel; a driveline integrated starter / generator (DISG) having a first side coupled to a second side of the driveline disconnect clutch; a starter other than the DISG having a base state in which the starter is not engaged with the engine; a transmission selectively coupled to the engine via the driveline disconnect clutch; and a controller having nonvolatile instructions executable to automatically stop the engine, providing driveline braking across the DISG while engine rotation is stopped, rotating a stopped engine over the starter other than the DISG when the DISG provides driveline braking and when the battery state of charge is greater than a threshold level.

In some examples, the vehicle system further includes additional commands to increase slip of a torque converter clutch when the driveline disconnect clutch is at least partially closed. The vehicle system further includes closing the driveline disconnect clutch after the engine is started. The vehicle system includes the DISG having a power output capacity greater than that of the other starter than the DISG. The vehicle system further includes a torque converter clutch and additional commands for increasing slip of the torque converter clutch during closing of the driveline disconnect clutch. The vehicle system also includes the DISG providing a charge to an energy storage device when providing driveline braking.

The methods and systems of 1 - 3 and 29 - 30 also provide for controlling driveline braking, comprising: providing driveline braking via an electric machine while rotation of an engine is stopped; and adjusting a torque of the electric machine in response to a condition of the engine. The method includes where the condition of the engine is an oil temperature. The method includes where the condition of the engine is a valve timing of the engine. The method includes where the condition of the engine is an engine coolant temperature. The method includes where the condition of the engine is an estimated engine brake torque. The method includes providing driveline braking via operating the electric machine in a generator mode. The method includes where the torque of the electric machine is changed as the condition of the engine changes.

The methods and systems of 1 - 3 and 29 - 30 also provide for controlling driveline braking, comprising: providing driveline braking via an electric machine while rotation of an engine is stopped; and adjusting a torque of the electric machine based on a braking torque of the engine. The method includes estimating engine braking torque based on engine oil temperature. The method includes estimating the braking torque of the engine based on a rotational speed of the electric machine. The method includes where the torque of the electric machine is a negative torque. The method includes where the electric machine is in a generator mode. The method includes where the braking torque of the engine is a deceleration fuel cutoff brake torque. The method includes where the braking torque of the engine is based on a position of a throttle.

The methods and systems of 1 - 3 and 29 - 30 also provide a vehicle system comprising: an engine; a dual mass flywheel (DMF) having a first side mechanically coupled to the engine; a driveline disconnect clutch having a first side mechanically coupled to a second side of the dual mass flywheel; a driveline integrated starter / generator (DISG) having a first side coupled to a second side of the driveline disconnect clutch; a starter other than the DISG having a base state in which the starter is not engaged with the engine; a transmission selectively coupled to the engine via the driveline disconnect clutch; and a controller having nonvolatile instructions executable to automatically stop the engine, provide driveline braking across the DISG while engine rotation is stopped, and adjust torque of the DISG to engine brake torque while providing driveline braking.

In some examples, the vehicle system further includes additional instructions for accelerating the engine to a speed of the DISG. The vehicle system further includes additional commands for reducing a negative torque provided by the DISG in response to a negative torque supplied by the engine to a driveline. The vehicle system further includes additional commands to start the engine via the starter other than the DISG. The vehicle system further includes additional commands to stop combustion in the engine cylinders after starting the engine. The vehicle system further includes additional commands for adjusting engine braking after stopping combustion in the engine cylinders.

The methods and systems of 1 - 3 and 29 - 30 also provide for controlling driveline braking, comprising: providing driveline braking via an electric machine while rotation of an engine is stopped; and automatically activating a device for consuming cargo delivered via the electric machine while the electric machine provides for driveline braking. The method includes where the device is activated in response to a state of charge of an electrical storage device exceeding a threshold level.

In one example, the method includes where the device is a heater. The method includes where the heater is a window deicer. The method includes where the heater is an emission device heater. The method includes where the device is a pump. The method includes where the pump is a fuel injection pump.

The methods and systems of 1 - 3 and 29 - 30 also provide for controlling driveline braking, comprising: providing driveline braking via an electric machine while rotation of an engine is stopped; and increasing the current supplied to a device while the electric machine provides driveline braking. The procedure includes that the increase in current based on a supercharging rate that is output by the electric machine. The method includes where the electric machine provides charge to an energy storage device while the electric machine provides driveline braking. The method includes where the current increase is based on a state of charge of an energy storage device. The method includes where the device is a pump. The method includes where the device is a heating device. The method includes where the device is a light.

The methods and systems of 1 - 3 and 29 - 30 also provide for controlling driveline braking, comprising: providing driveline braking via an electric machine while rotation of an engine is stopped; automatically activating a device to consume charge delivered via the electric machine while the electric machine provides driveline braking; Rotating the engine in response to a state of charge of an energy storage device; and stopping the rotation of the engine when the state of charge of the energy storage device is less than a threshold level.

In one example, the method includes where the device for consuming cargo delivered via the electric machine is a device having an operating condition that is not visible or audible to the driver. The method includes where the device consuming charge delivered via the electric machine is a heating device. The method includes where the heater supplies heat to the ambient air. The method includes where the heater supplies heat to an exhaust system. The method further includes stopping the provision of driveline braking via the electric machine when the engine is rotating.

The methods and systems of 1 - 3 and 29 - 30 also provide for controlling driveline braking, comprising: providing driveline braking via an electric machine while rotation of an engine is stopped; Operating the electric machine in a speed control mode in response to a request to provide driveline braking via the engine; Starting the engine; Accelerating the engine to a speed of the electric machine; and closing an open driveline disconnect clutch in response to the engine speed being substantially equal to the speed of the electric machine. The method includes where the engine is started via a starter other than the electric machine.

In some examples, the method includes where the request for providing driveline braking via the engine is based on a state of charge of an energy storage device. The method includes where the request for providing driveline braking via the engine occurs in response to the state of charge of the energy storage device being greater than a threshold amount of charge. The method further includes adjusting the slip of a torque converter clutch in response to the closing of the open driveline disconnect clutch. The method includes increasing the slip of the torque converter clutch. The method includes where the electric machine provides torque to start the engine.

The methods and systems of 1 - 3 and 29 - 30 also provide for controlling driveline braking, comprising: providing driveline braking via an electric machine while rotation of an engine is stopped; Starting and turning the engine; Injecting fuel into the engine; Accelerating the engine to a speed of the electric machine; and interrupting the injection of fuel into the engine and providing driveline braking via the engine while the electric machine outputs less than a threshold amount of power. The method further includes closing a driveline disconnect clutch in response to the engine speed being substantially equal to the speed of the electric machine.

In one example, the method further includes operating the electric machine in a speed control mode during closing of the driveline disconnect clutch. The method further includes increasing the slip of a torque converter clutch during closing of the driveline disconnect clutch. The method includes where the engine is started in response to the charge of an energy storage device exceeding a threshold charge. The method includes where the torque of the electric machine is reduced in response to the engine braking torque increasing after the injection of fuel into the engine is discontinued. The method includes where the engine is started via a starter other than the electric machine.

The methods and systems of 1 - 3 and 29 - 30 also provide a vehicle system comprising: an engine; a dual mass flywheel (DMF) having a first side mechanically coupled to the engine; a driveline disconnect clutch having a first side mechanically connected to a second side of the Dual mass flywheel is coupled; a driveline integrated starter / generator (DISG) having a first side coupled to a second side of the driveline disconnect clutch; a starter other than the DISG having a base state in which the starter is not engaged with the engine; a transmission selectively coupled to the engine via the driveline disconnect clutch; and a controller having non-volatile commands executable to automatically stop the engine, providing driveline braking across the DISG while engine rotation is stopped, starting the engine in response to a state of charge of an energy storage device to stop combustion in the engine As the engine rotates, and to provide driveline braking via the engine. In this way, the system may implement electrical driveline braking into mechanical driveline braking.

In some examples, the vehicle system further includes additional instructions for accelerating the engine to a speed of the DISG. The vehicle system further includes additional commands to close the driveline disconnect clutch when the engine speed is substantially equal to the DISG speed. The vehicle system further includes additional commands to start the engine via the starter other than the DISG. The vehicle system further includes additional commands to stop combustion in the engine cylinders after starting the engine. The vehicle system further includes additional commands for adjusting engine braking after stopping combustion in the engine cylinders.

Regarding 31 FIG. 3 is a flowchart of a method for controlling a driveline during vehicle braking provided via the vehicle driveline. The procedure of 31 can be used as executable instructions in a nonvolatile memory in the system of 1 - 3 be saved.

at 3102 assess the procedure 3,100 whether the engine is off and the DISG is in a regeneration mode (eg, whether the DISG converts the vehicle's kinetic energy to electrical energy) or not. In one example, it may be judged that an engine has stopped rotating when engine speed is zero. It may be determined that the DISG is in a regeneration mode when power is flowing from the DISG and the DISG is providing negative torque to the driveline. If the procedure 3,100 judges that the engine is not spinning and the DISG is in regeneration mode, the answer is yes and the procedure 3,100 go to 3104 further. Otherwise, the answer is no and the procedure 3,100 continue to the end.

at 3104 switches the procedure 3,100 a gear in a gear that allows the DISG speed to remain below a base DISG speed. The base DISG speed is a speed at which the DISG can provide a rated torque (eg, maximum DISG torque). If the DISG speed is greater than the base DISG speed, the DISG torque is inversely proportional to the DISG speed. Consequently, if the DISG speed is greater than the base DISG speed, the transmission may be upshifted such that the DISG speed is less than the DISG base speed. If the vehicle speed is such that the DISG speed can not be reduced to less than the DISG base speed by upshifting the transmission, the transmission may be switched to a gear that allows the DISG to rotate at a speed that is on the next to the DISG base speed. In addition, the DISG may be included in some examples 3104 in a speed control mode instead of waiting for an increase in the driver request torque. The procedure 3,100 go to 3106 after the transmission is shifted so that the DISG speed is close to or less than the DISG base speed.

at 3106 assess the procedure 3,100 Whether there is a requirement for increased positive driveline torque or not. A request for increased positive driveline torque may be in response to increasing driver demand torque. The driver request torque may be determined by an accelerator pedal or a control unit. If the procedure 3,100 judged that there is a request for an increased positive driveline torque (eg, for accelerating the vehicle), the answer is Yes and the method 3,100 go to 3108 further. Otherwise, the answer is no and the procedure 3,100 returns 3104 back.

at 3108 puts the procedure 3,100 the capacity of the torque converter clutch (TCC). In one example, the TCC capacity is set to the desired torque converter output torque minus an amount of torque that the torque converter would produce with a fully open TCC. The amount of torque the converter would produce with a fully open TCC may be determined by the torque converter impeller speed and the torque converter turbine speed. In particular, the torque converter impeller speed and the torque converter turbine speed index a function or table stored in memory that stores the engine torque Outputting torque converter output torque based on torque converter impeller speed and torque converter turbine speed. Once the TCC capacity is determined, it is output to the TCC. The procedure 3,100 go to 3110 continue after the TCC capacity is set.

at 3110 For example, the DISG is transitioned from a torque control mode to a speed control mode. In the speed control mode, the DISG torque is adjusted to provide a desired DISG speed. The desired DISG speed may be constant or it may vary with vehicle operating conditions. The procedure 3,100 go to 3112 after the DISG is put into a speed control mode.

at 3112 puts the procedure 3,100 the DISG speed to adjust the torque converter output torque. Specifically, the torque converter torque is adjusted from a negative torque to a positive torque via the setting of the DISG speed. In one example, a desired torque converter output torque profile is stored in memory and retrieved during a driveline brake transition (eg, negative driveline torque) to driveline acceleration (eg, positive driveline torque). The desired torque converter output torque profile determines the torque converter output torque based on a change in driver demand torque and current transmission gear. The desired torque converter output torque and turbine speed are input to a function or table that outputs the torque converter impeller speed. The table or function describes a torque converter transfer function. The DISG is commanded to torque converter impeller speed so that the torque converter outputs the desired torque converter output torque. After the DISG completes the desired torque converter output profile, the DISG torque is adjusted to provide the desired driver demand torque. In this manner, the DISG speed is controlled as a function of the torque converter turbine speed and the desired torque converter output. In other words, the actual torque converter output torque is controlled as a function of torque converter impeller speed and turbine speed.

In an alternative example, the DISG speed adjusts the torque converter output torque by varying the torque converter impeller speed relative to the torque converter turbine speed. In particular, the DISG increases the torque converter output torque from a negative torque to a positive torque via increasing the DISG speed. The torque converter output torque is increased faster to reduce backlash between the transmission and the driveline gears. The torque converter output torque is reduced when the clearance between the gear sets is reduced, so that a gear tooth to gear tooth impact can be reduced.

The gear tooth to gear tooth speed of the gear game traversal is set from gear tooth to gear tooth by adjusting the torque converter output torque as a function of the estimated rotational speed, for example. In one example, the gear tooth speed to gear tooth speed is the difference between the torque converter turbine speed and either the transmission output speed or the wheel speed. The speed difference between the turbine speed and the transmission output speed or wheel speed is relatively small until driveline shaft rotation is mitigated. A positive torque converter output torque is increased by increasing the DISG speed in response to a small difference in speed between the torque converter turbine and the transmission output speed or wheel speed. The DISG output speed is increased rapidly when the difference in torque converter turbine and transmission output speed or wheel speed is small so that the gear teeth separate. The speed difference increases as the gear teeth transition from being in contact to being out of contact. The DISG speed is reduced as the difference between the torque converter turbine and transmission output speed or wheel speed increases, so that the impact force between the gear sets can be reduced.

In one example, once the torque converter impeller speed minus the transmission output shaft speed or wheel speed exceeds a threshold speed, the DISG speed is reduced to reduce the impact force from tooth to tooth. The DISG speed is increased after the difference between the torque converter turbine and transmission output speed or wheel speed is less than a threshold speed such that the gear teeth remain in contact after transition from the negative driveline torque to the positive driveline torque. The procedure 3,100 go to 3114 continue after the DISG game setting starts.

at 3114 assess the procedure 3,100 Whether a gear play is reduced to less than a threshold amount or not. In one example, the gear play is determined to be less than a threshold amount when a positive torque has been applied to the driveline and a difference between the torque converter turbine speed and the transmission output speed or wheel speed is less than a threshold level. If the procedure 3,100 judges that the gear play is reduced to less than a threshold amount, the answer is Yes and the method 3,100 go to 3116 further. Otherwise, the answer is no and the procedure 3,100 returns 3112 back.

at 3116 increases the procedure 3,100 the DISG output torque. Since the DISG is in the speed control mode, the DISG output torque may be increased in response to driveline torque being transmitted to the engine and reducing driveline rotational speed. In other words, the positive DISG torque may be increased as the DISG speed decreases from the desired DISG speed. In another example, the DISG output torque may be increased while the DISG is in the speed control mode by increasing the DISG torque based on the driveline disconnect clutch torque (eg, the amount of torque transmitted from the DISG to the engine via the DISG becomes). The desired driveline disconnect clutch torque may be stored in memory in a function or table and the torque boost applied to the DISG during an engine restart in response to the disconnect clutch closing. The procedure 3,100 go to 3118 after the DISG output torque is adjusted to start the engine.

at 3118 starts the procedure 3,100 the engine new. The engine is restarted via at least partially closing the driveline disconnect clutch and supplying spark and fuel to the engine. In some examples, closing the driveline disconnect clutch and increasing the DISG output torque may occur simultaneously, such that any driveline torque disturbance may be reduced. The procedure 3,100 go to 3120 continue after the engine starts.

at 3120 suppresses the process 3,100 Engine torque disturbances that may be delivered to the driveline. For example, during engine startup, the engine may consume the driveline torque to accelerate during takeoff. The engine torque disturbances may be suppressed in response to a change in driveline speed on the DISG. Since the DISG is in the speed control mode following a desired speed, the DISG torque may be increased as the engine consumes the driveline torque and slows the driveline. In addition, if the engine accelerates after launch and provides torque to the driveline, the DISG torque may be reduced such that the net torque delivered to the driveline via the DISG and the engine remains substantially constant (eg, ± 30 Nm). In this manner, the driveline speed may be controlled in a closed loop manner via adjustment of the DISG torque.

In another example, driveline torque disturbances may be suppressed over DISG open loop torque settings. For example, if the disconnect clutch begins to close, the DISG torque may be increased while the DISG is in speed control mode. In particular, the DISG torque may be adjusted via the adding of the driveline disconnect clutch torque to the DISG torque command. The DISG torque command is further adjusted in response to the DISG speed. Thus, if the driveline disconnect clutch torque is under- or over-etched, the DISG speed control loop eliminates the driveline disconnect torque error that was added to the DISG torque. The driveline torque disturbances suppressed during engine startup may be suppressed from the time the engine cranking begins until the engine reaches the DISG speed and the driveline disconnect clutch is fully closed. The procedure 3,100 go to 3122 after drivetrain disturbances are suppressed during engine startup.

at 3122 provides the procedure 3,100 the desired torque to the drive train. The desired torque can only be delivered via the DISG, only via the engine or via the engine and the DISG. In one example, the DISG torque and the engine torque are provided as fractions of a driver demand torque, as determined by an accelerator pedal. For example, if the driver demand torque is determined to be 100 Nm on the torque converter impeller, the engine may deliver 80% of the driver demand torque, or 80 Nm, while the DISG is delivering 20% or 20 Nm, so that 100 Nm is delivered to the torque converter impeller. The procedure 3,100 continues to the end after the desired torque is delivered to the driveline.

It should be noted that in some examples 3116 - 3120 at the same time with 3108 - 3114 so that the driveline torque can better respond to driver demand torque. Shifting the transmission into a gear that allows the DISG to operate below the base DISG speed may increase the chance that the DISG will simultaneously have the torque capacity to restart the engine and mitigate the gear impact of the driveline gear clearance.

Regarding 32 FIG. 10 is an example sequence for reducing the gear play impact of a driveline according to the method of FIG 31 shown. The sequence of 32 can through the system of 1 - 3 to be provided.

The first diagram from the top of 32 represents the vehicle speed as a function of time. The y-axis represents the vehicle speed and the vehicle speed increases in the direction of the y-axis arrow. The X-axis represents the time and the time increases from the left side of the figure to the right side of the figure.

The second diagram from the top of 32 represents the driver request torque as a function of time. The Y axis represents the driver request torque, and the driver request torque increases in the direction of the Y axis arrow. The X-axis represents the time and the time increases from the left side of the figure to the right side of the figure.

The third diagram from the top of 32 represents the engine state as a function of time. The Y axis represents the engine state and the engine rotates when the engine state curve is at a higher level. The engine stopped rotation when the engine state curve is at a lower level. The X-axis represents the time and the time increases from the left side of the figure to the right side of the figure.

The fourth diagram from the top of 32 represents the duty cycle of the torque converter clutch (TCC) as a function of time. The Y axis represents the TCC duty cycle and the TCC duty cycle increases in the direction of the Y axis arrow. The X-axis represents the time and the time increases from the left side of the figure to the right side of the figure. The TCC closing force increases as the TCC duty cycle increases. The TCC may transfer less torque between the DISG and the transmission as the TCC duty cycle increases because torque converter torque multiplication may be reduced. The TCC is locked (eg, the torque converter impeller speed is equal to the torque converter turbine speed) when the TCC curve is near the Y-axis arrow.

The fifth diagram from the top of 32 represents the transmission gear as a function of time. The Y-axis represents the gear and specific gears are indicated along the Y-axis. The X-axis represents the time and the time increases from the left side of the figure to the right side of the figure.

The sixth diagram from the top of 32 represents the DISG speed as a function of time. The Y axis represents the DISG speed and the DISG speed increases in the direction of the Y axis arrow. The X-axis represents the time and the time increases from the left side of the figure to the right side of the figure. The horizontal line 3202 represents the base DISG speed.

At time T _68, the vehicle speed is at an elevated level as well as the driver request torque. The engine works and burns air / fuel mixtures. The TCC is locked as indicated by the TCC duty cycle being close to the Y-axis label. The transmission is in fifth gear and the DISG speed is at a medium level above the DISG base speed 3202 ,

At time T ₆₉ , the driver request torque is reduced to a low value in response to a driver releasing, for example, an accelerator pedal. The vehicle speed, driver demand torque, engine state, TCC duty cycle, transmission gear, and DISG speed remain at similar levels as at time _T68 . The DISG, however, contemplates generating positive torque and consuming electrical energy to generate negative torque and generate electrical energy. The fuel and spark supply to the engine is also stopped so that the engine decelerates but continues to rotate without receiving fuel.

Between time T ₆₉ and time T ₇₀ , the vehicle speed decreases as does the DISG speed. The engine continues to rotate as indicated by the engine state staying at a higher level, and the TCC duty cycle also remains at a higher level with the TCC locked. The transmission remains in 5th gear and the driver demand torque remains at a lower level.

At time T ₇₀ , engine rotation is stopped in response to the low driver request torque, as indicated by the engine state flag transitioning to a lower level. The driveline disconnect clutch (not shown) is opened in response to the engine stopping and the DISG is transitioned into a speed control mode. The DISG speed and vehicle speed are further reduced and the transmission remains in 5th gear.

Between time T ₇₀ and time T ₇₁ , vehicle speed and DISG speed continue to decrease. In this example, if downshifting allows the DISG speed to remain below the base DISG speed, the transmission shuts down. The DISG speed is commanded to a speed based on the driver demand torque, the vehicle speed, and the selected gear. For example, the transmission is held in 5th gear and the DISG speed is reduced to less than the base DISG speed. The DISG speed continues to decrease to a threshold speed at which the DISG is below the DISG base speed when the transmission is shifted to 4th gear. The transmission shifts down to 4th gear when the DISG speed is less than the threshold speed, and the DISG speed is increased to a speed based on the DISG speed before shifting and the new gear ratio.

In some examples, during the onset of vehicle deceleration or a decrease in driver demand torque, the current DISG speed may be greater than the DISG base speed. In these cases, the transmission may be upshifted at the onset of vehicle deceleration or in response to the driver demand torque decrease such that the DISG speed is reduced to less than the DISG base speed. By decreasing the DISG speed to less than the DISG base speed, it may be possible to provide torque from the DISG to restart the engine to reduce the impact of gear tooth to gear tooth, which is due to gear play. The gears are downshifted at times that allow the DISG speed to remain lower than the DISG base speed.

The TCC duty cycle is also reduced in response to the driveline disconnect clutch state (not shown), vehicle speed, and driver request torque. The TCC application force and the TCC duty cycle are modulated to reduce any driveline torque disturbance that may result from opening the driveline disconnect clutch. The engine remains stopped as indicated by the engine state being at a lower level. The driver request torque also remains low.

It should also be noted that the driveline gear teeth may have transitioned from the transmission of torque from the front surfaces of the gear teeth to the back surfaces of the gear teeth as the driveline transitions from generating a positive torque to providing a negative or brake torque. The impact of gear tooth on gear tooth may result when the driveline reverts to producing positive torque when the transitions are not managed in a desired manner.

At time T ₇₁ , the driver request torque is increased in response to a driver or controller input. The DISG speed is increased to separate the teeth in the driveline. The DISG is accelerated as a function of the speed difference from gear tooth to gear tooth. In particular, the DISG is accelerated at a higher rate when the gear teeth are at the same speed to separate the teeth.

At time T ₇₂ , the DISG acceleration is reduced and the DISG may slow as the speed difference between the gear teeth increases. Slowing the DISG can reduce the impact force from gear tooth to gear tooth by reducing the speed between the gear teeth. Shortly after time T ₇₂ , the DISG acceleration is increased after the space or clearance between the gear teeth has been removed. By waiting with the acceleration of the DISG until after the gear teeth are in contact, it may be possible to reduce driveline torque disturbances and provide smoother transitions from negative to positive torque. The TCC slip and TCC application force between time T ₇₁ and time T ₇₃ are also adjusted and / or modulated to reduce torque disturbances in the driveline. The torque from the DISG begins to accelerate the vehicle and the DISG is placed in a torque control mode.

At time T ₇₃ , a spark and fuel are supplied to the engine and the driveline disconnect clutch is closed so that the engine is started. The TCC duty cycle and TCC apply force are modulated to reduce any driveline torque disturbance that may result from the driveline disconnect clutch closing during engine startup. The TCC is locked after the engine started is to improve the power train efficiency. Further, the transmission begins shifting through the gears to accelerate the vehicle.

In this way, the play and the impact between the driveline teeth can be reduced when a driveline is transitioned from a brake mode to a torque generation mode. By adjusting the DISG speed and the DISG torque in this manner, it may be possible to reduce driveline torque disturbances that may be noticeable to a driver.

Consequently, the methods and systems of 1 - 3 and 31 - 32 controlling the driveline clearance, comprising: shifting a transmission into a gear that allows an electric machine coupled to the transmission to operate at a speed lower than a base speed of the electric machine in response to a reduction in driver demand torque; and reducing the impact of gear tooth to gear tooth via operating the electric machine in a speed control mode during a driveline torque transition from a negative torque to a positive torque. The method further includes reducing a torque converter clutch application force during the driveline torque transition from the negative torque to the positive torque. The method further includes stopping the rotation of an engine in response to the driver demand torque decrease.

In one example, the method further comprises opening a driveline disconnect clutch in response to the driver demand torque decrease. The method further comprises adjusting the speed of the electric machine in response to a difference in speed between a first gear tooth and a second gear tooth during the driveline torque transition from the negative torque to the positive torque. The method further includes downshifting the transmission in response to the vehicle speed. The method includes where, immediately prior to operating the electric machine in the speed control mode during the driveline torque transition, the electric machine is operated from the negative torque to the positive torque in a torque control mode.

The methods and systems of 1 - 3 and 31 - 32 also provide for controlling driveline play, comprising: reducing the impact of gear tooth to gear tooth via operating an electric machine in a speed control mode during a driveline torque transition from a negative torque to a positive torque; and accelerating the electric machine to disconnect a first gear tooth and a second gear tooth during the driveline torque transition from the negative torque to the positive torque. The method further includes slowing the electric machine in response to an increase in a rotational speed difference between the first gear tooth and the second gear tooth. The method further comprises accelerating the electric machine in response to a reduction in the speed difference between the first gear tooth and the second gear tooth after slowing the electric machine.

In one example, the method includes transitioning from negative torque to positive torque in response to an increase in driver demand torque. The method further includes opening a driveline disconnect clutch mechanically coupled to the electric machine prior to reducing the impact of gear tooth to gear tooth in response to a reduction in driver demand torque. The method further includes reducing a torque converter clutch application force in response to a reduction in driver demand torque prior to reducing the impact of gear tooth to gear tooth. The method includes where the speed of the electric machine is controlled as a function of a speed difference between a first gear tooth and a second gear tooth.

The methods and systems of 1 - 3 and 31 - 32 also provide a vehicle system comprising: an engine; a dual mass flywheel having a first side mechanically coupled to the engine; a driveline disconnect clutch having a first side mechanically coupled to a second side of the dual mass flywheel; a driveline integrated starter / generator (DISG) having a first side coupled to a second side of the driveline disconnect clutch; a transmission selectively coupled to the engine via the driveline disconnect clutch; and a controller having nonvolatile instructions executable to automatically stop engine rotation, reduce an impact of gear tooth to gear tooth via operating the DISG in a speed control mode during a driveline torque transition from a negative torque to a positive torque, and increase engine rotation while reducing the impact of gear tooth to gear tooth.

In one example, the vehicle system includes initiating engine rotation via closing the driveline disconnect clutch. The vehicle system further includes additional commands for adjusting a torque converter clutch application force while reducing the impact of gear tooth to gear tooth. The vehicle system further includes additional commands to open the driveline disconnect clutch in response to a driver request torque. The vehicle system further includes additional commands to at least partially close the driveline disconnect clutch to start the engine in response to a driver request torque. The vehicle system further includes additional commands to shift the transmission into a gear that rotates the DISG at a speed that is less than the DISG base speed during vehicle deceleration.

Regarding 33 A flowchart of a method of transferring vehicle braking from driveline to friction brakes is shown. The procedure of 33 can be used as executable commands in a nonvolatile memory in the system of 1 - 3 be saved.

Regarding 3302 appreciates the process 3300 the vehicle mass and the road inclination. In one example, the road grade may be estimated or determined via an inclinometer. The vehicle mass can be determined as at 904 of the procedure 900 described. The procedure 3300 go to 3304 after the vehicle mass and road grade are determined.

at 3304 assess the procedure 3300 Whether the vehicle slows down or whether a driver has reduced a driver torque request or not. In one example, the vehicle deceleration may be determined via the decrease in vehicle speed. A reduced driver request torque may be determined by releasing an accelerator pedal. If the procedure 3300 judged that the vehicle deceleration or a reduced driver request is present, the answer is Yes and the method 3300 go to 3306 further. Otherwise, the answer is no and the procedure 3300 continue to the end.

at 3306 assess the procedure 3300 Whether the state of charge (SOC) of an energy storage device is less than a threshold charge amount or not. In one example, the SOC may be determined by measuring the battery voltage. If the energy storage device SOC is less than a threshold charge amount, the answer is Yes and the method 3300 go to 3308 further. Otherwise, the answer is no and the procedure 3300 go to 3312 further.

at 3308 stops the procedure 3300 the engine rotation and opens the driveline disconnect clutch. The engine is stopped by stopping the supply of the engine with sparks and fuel. The procedure 3300 go to 3310 after the engine rotation is stopped and the driveline disconnect clutch is opened.

at 3310 operates the procedure 3300 DISG in generator mode and charges the energy storage device. The DISG provides a negative torque to the vehicle driveline in generator mode. In one example, the amount of negative torque the DISG provides to the driveline may be adjusted in response to the vehicle speed and driver demand torque. In another example, the amount of negative torque that the DISG provides to the DISG may be adjusted to an estimated engine brake torque, as described herein under current operating conditions. The rate of vehicle deceleration may also be at 3310 stored in memory. The procedure 3300 returns 3304 back after the DISG begins to charge the energy storage device.

at 3312 the procedure begins 3300 to reduce the negative DISG torque. In some examples, the driveline disconnect clutch may be further closed so that the engine may provide for driveline braking. In one example, the negative DISG torque is reduced toward zero torque in response to an amount of torque transferred to the engine via the driveline disconnect clutch. The reduction in negative DISG torque is based on a reduction in the charging current. The procedure 3300 go to 3314 after the DISG torque starts to decrease.

so dass T_wh = m·a·R_rr + R_rr·g·m·sin(Θ) wobei F gleich der Kraft zum Beschleunigen/Verlangsamen des Fahrzeugs ist, m die Fahrzeugmasse ist, R_rr der Rollradius des Rades ist, a die Fahrzeugbeschleunigung darstellt, g die Schwerkraftbeschleunigung ist und θ der Winkel der Straße ist. Das Verfahren 3300 geht zu 3318 weiter, nachdem das Raddrehmoment bestimmt ist.at 3314 appreciates the process 3300 the wheel torque over the current road gradient and vehicle deceleration. The wheel torque can be estimated on the basis of the following equations:

so that T_wh = m · a · R_rr + R_rr · g · m · sin (Θ) where F equals the vehicle accelerating / decelerating force, m is the vehicle mass, R_rr is the rolling radius of the wheel, a is the vehicle acceleration, g is the gravitational acceleration, and θ is the angle of the road. The procedure 3300 go to 3318 continue after the wheel torque is determined.

at 3316 puts the procedure 3300 the brake feed oil pressure in response to the vehicle wheel torque and the decrease in negative DISG torque (eg, toward zero DISG torque). In particular, the process increases 3300 simultaneously the oil pressure supplied to the friction brakes of the vehicle and reduces the negative DISG torque. The vehicle friction braking force is increased at a rate that compensates for the decrease in negative DISG torque to provide an equivalent rate of vehicle deceleration. In one example, an open loop brake pipe oil pressure, which may be related to the brake application force, is retrieved from a table or function that includes empirically determined brake pipe oil pressures in response to a desired wheel braking torque. The desired wheel braking torque provided by the friction brakes is the wheel torque of 3314 minus the DISG torque reduction multiplied by the current gear ratio and axle ratio. The brake pipe oil pressure is increased to the pressure that provides the desired wheel braking torque. In this way, closed-loop control of vehicle braking based on wheel torque may be achieved. Additionally, in some examples, the driveline disconnect clutch may be closed and the engine may be rotated without fuel to provide the driveline braking torque in response to the decrease in DISG torque and other operating conditions. The procedure 3300 increases after the beginning of the brake line oil pressure increase and after the beginning of the negative DISG torque decrease 3318 further.

In other examples, the brake line oil pressure may be increased by an estimate of the brake application force in the open loop, and the brake application force may be further adjusted based on a difference between the desired vehicle speed and the actual vehicle speed. In this way, the vehicle speed difference may be a closed loop parameter for adjusting the friction braking force.

at 3318 assess the procedure 3300 Whether or not there is a brake request from the driver. In one example, a brake request may be determined by a driver from a position of a brake pedal. If the procedure 3300 If a brake request is judged by a driver, the answer is Yes and the method 3300 go to 3320 further. Otherwise, the answer is no and the procedure 3300 go to 3322 further.

at 3320 the brake line oil pressure is increased in response to a driver request input. In one example, the brake line oil pressure for the friction brakes is increased in proportion to the displacement of a brake pedal. The procedure 3300 go to 3322 after the brake pipe oil pressure is increased in response to the driver brake command.

at 3322 assess the procedure 3300 whether the vehicle is stopped or not. The vehicle may be judged stopped when the vehicle speed is zero. If it is judged that the vehicle is stopped, the answer is Yes and the method 3300 ends. If it is judged that the vehicle is moving, the answer is no and the method 3300 returns 3312 back.

Regarding 34 FIG. 12 is an example sequence for transferring vehicle braking from driveline to friction brakes according to the method of FIG 33 shown. The sequence of 34 can through the system of 1 - 3 to be provided.

The first diagram from the top of 34 represents the vehicle speed as a function of time. The y-axis represents the vehicle speed and the vehicle speed increases in the direction of the y-axis arrow. The X-axis represents the time and the time increases from the left side of the figure to the right side of the figure.

The second diagram from the top of 34 represents the driveline disconnect clutch state as a function of time. The Y axis represents the driveline disconnect clutch state and the driveline disconnect clutch is closed when the driveline disconnect clutch state curve is near the Y axis arrow. The driveline disconnect clutch is open when the driveline disconnect clutch state curve is near the X axis. The X-axis represents the time and the time increases from the left side of the figure to the right side of the figure.

The third diagram from the top of 34 represents the engine state as a function of time. The Y axis represents the engine state and the engine rotates when the engine state curve on a higher level. The engine stopped rotation when the engine state curve is at a lower level. The X-axis represents the time and the time increases from the left side of the figure to the right side of the figure.

The fourth diagram from the top of 34 represents the battery state of charge (SOC) as a function of time. The Y axis represents the battery SOC and the SOC increases in the direction of the Y axis arrow. The X-axis represents the time and the time increases from the left side of the figure to the right side of the figure.

The fifth diagram from the top of 34 represents the DISG torque as a function of time. The Y axis represents the DISG torque and the DISG torque can be positive or negative. The X-axis represents the time and the time increases from the left side of the figure to the right side of the figure.

The sixth diagram from the top of 34 represents the brake line oil pressure of the friction brakes as a function of time. The Y axis represents the brake line oil pressure and the brake line oil pressure increases in the direction of the Y axis arrow. The X-axis represents the time and the time increases from the left side of the figure to the right side of the figure.

The seventh diagram from the top of 34 represents the vehicle wheel torque as a function of time. The Y axis represents the vehicle wheel torque and the vehicle wheel torque increases in the direction of the Y axis arrow. The X-axis represents the time and the time increases from the left side of the figure to the right side of the figure.

At time T ₇₄ , the vehicle speed is increased, the engine is operating and the driveline disconnect clutch is closed. The battery SOC is relatively low and decreases as the DISG delivers positive torque to the driveline. The friction brakes are not applied as indicated by the brake line oil pressure being at a low level. The wheel torque is positive.

At time T ₇₅ , the driver releases the accelerator pedal (not shown). Shortly thereafter, the DISG torque transitions from positive to negative in response to a low driver request torque from the accelerator pedal. By transitioning to a negative torque, the DISG provides driveline braking to slow down the vehicle. Further, the DISG generates charge and delivers the charge to the battery as indicated by the increasing battery SOC. The friction brake line pressure remains at a low level, indicating that the friction brakes are not being applied. The wheel torque transitions from a positive torque to a negative torque in response to the DISG transitioning to providing negative torque. In addition, the driveline disconnect clutch is opened and engine rotation is stopped. The engine is stopped to save fuel and the disconnect clutch is opened so that the DISG can provide all the driveline braking. The amount of driveline braking that the DISG provides may be empirically determined and stored in memory as a function of vehicle speed and driver demand torque.

In this example, the driver does not apply the brake pedal after releasing the accelerator pedal. However, in some examples, the driver may apply the brakes after releasing the accelerator pedal. In such examples, the brake pipe pressure may increase in response to the driver's brake command.

Between time T ₇₅ and time T ₇₆ , the negative DISG torque gradually increases until a desired driveline braking torque is established. The negative wheel torque also increases as the driveline braking torque increases. The driver does not apply the brake pedal and the battery SOC increases. The driveline disconnect clutch remains open and the engine remains in a stopped state.

At time T ₇₆ , the battery SOC reaches a threshold amount (eg, fully charged) in response to the DISG supplying charge to the battery. The negative DISG torque is reduced and the amount of charge delivered to the battery is reduced. The brake pipe oil pressure is also increased so that the wheel braking torque can be maintained via the friction brakes. The brake line oil pressure is increased based on the reduction in negative DISG torque. In one example, the friction braking force is adjusted based on the wheel torque and the DISG torque reduction. In some other examples, the friction braking force applied to slow the wheel rotation may be adjusted based on a difference between a desired vehicle speed and an actual vehicle speed. The vehicle speed continues to decrease and the driveline disconnect clutch remains open. Furthermore, the engine remains stopped.

At time T ₇₇ , the driveline disconnect clutch is closed and the engine is rotated without injecting fuel in response to the negative DISG torque is reduced, and in response to operating conditions. For example, the engine may be rotated in response to the DISG torque decrease and a time since the DISG torque change. The engine is rotated without fuel to provide brake torque. And engine braking torque may be adjusted via activation and deactivation of valves and / or adjustment of intake manifold pressure via a throttle and / or valves. The brake pipe oil pressure is reduced in response to the driveline braking torque provided by the engine. In particular, the brake pipe oil pressure is reduced by an amount that reduces the torque provided by the friction brakes so that equivalent vehicle braking is provided even if driveline braking is increased by rotating the engine without fuel.

At time T ₇₈ , the vehicle speed approaches zero speed. The driveline disconnect clutch is opened and engine rotation is stopped in response to the vehicle speed being reduced to a threshold vehicle speed. The battery SOC remains at a higher level because the DISG does not provide positive torque to the driveline and drains battery charge. The brake line oil pressure increases when engine braking stops. Increasing the brake line oil pressure increases the force applied by the friction brakes to the wheels.

At time T ₇₉ , the vehicle speed reaches zero and the wheel torque and brake pipe oil pressure are reduced to zero. In some examples, the brake pipe oil pressure may be maintained when the vehicle speed reaches zero such that the vehicle remains at zero speed until the driver increases the driver demand torque via the accelerator pedal. The engine remains stopped and the driveline disconnect clutch remains in an open state.

In this manner, the friction brakes may be applied to slow the vehicle when driveline braking is reduced in response to the battery SOC. Further, the engine rotation may be stopped and started to further control driveline braking. The friction brakes may be applied based on an estimated wheel torque and / or a difference between the desired vehicle speed and the actual vehicle speed.

Consequently, the methods and systems of 1 - 3 and 33 - 34 A vehicle brake comprising: providing a driveline braking torque to a vehicle without applying a friction braking torque to the vehicle; and decreasing the driveline braking torque while increasing the friction braking torque for the vehicle in response to an energy storage device charge state, wherein the friction braking torque is increased by the same amount that the driveline braking torque is reduced. In this way, the vehicle may transition from driveline braking to friction braking in a manner that may be less noticeable to a driver.

In one example, the method includes where a rate at which the driveline braking torque is reduced is equivalent to a rate at which the friction brake torque is increased. The method includes where an engine of the vehicle is not rotating while the driveline braking torque is being delivered to the vehicle. The method includes where a driveline disconnect clutch is open while providing the driveline braking torque. The method includes where the driveline braking torque is provided in response to driver demand torque less than a threshold torque. The method includes where the friction braking torque is further increased in response to a driver braking request.

The methods and systems of 1 - 3 and 33 - 34 also provide vehicle braking, comprising: providing a driveline braking torque to a vehicle without applying friction braking torque to the vehicle; Estimating the vehicle wheel torque; and decreasing the driveline braking torque while increasing the friction braking torque for the vehicle in response to the estimated vehicle wheel torque and the energy storage device charge state. The method includes where the friction braking torque is increased in response to the estimated vehicle wheel torque. The method includes where the estimated vehicle wheel torque is based on an estimated vehicle mass.

In some examples, the method includes where the estimated vehicle wheel torque is based on vehicle acceleration. The method further includes rotating an engine without providing the engine with fuel. The method further includes adjusting the friction brake torque in response to an engine brake torque estimate. The method includes stopping an engine of the vehicle.

The methods and systems of 1 - 3 and 33 - 34 also provide a vehicle system comprising: an engine; a dual mass flywheel having a first side mechanically coupled to the engine; a driveline disconnect clutch having a first side mechanically coupled to a second side of the dual mass flywheel; a driveline integrated starter / generator (DISG) having a first side coupled to a second side of the driveline disconnect clutch; a transmission selectively coupled to the engine via the driveline disconnect clutch; Friction brakes; and a controller having nonvolatile instructions executable to automatically stop engine rotation, provide driveline braking torque via the DISG, and apply the friction brakes while reducing driveline braking torque.

In one example, the vehicle system further includes instructions for applying the friction brakes based on an estimated wheel torque. The vehicle system further includes additional instructions for reducing driveline braking torque in response to an energy storage device charge state. The vehicle system includes where the driveline braking torque is reduced in response to the energy storage device state of charge being greater than a threshold amount of charge. The vehicle system further includes instructions for applying the friction brakes based on the vehicle speed. The vehicle system includes applying the friction brakes via increasing the brake line oil pressure. The vehicle system further includes additional commands for reducing the friction brake application force in response to a vehicle speed of zero.

Regarding 35 FIG. 10 is a flowchart of a method of reducing driveline torque interference with gear play when transitioning from driveline braking to vehicle acceleration while no gear change is taking place. The procedure of 35 can be used as executable commands in a nonvolatile memory in the system of 1 - 3 be saved.

at 3502 assess the procedure 3500 Whether the vehicle slows down or whether the driver has at least partially released the accelerator pedal or not. The procedure 3500 can judge that monitoring the vehicle speed slows down the vehicle. The procedure 3500 may judge in response to the accelerator pedal position that the driver has at least partially released the accelerator pedal. If the procedure 3500 judged that the driver has partially released the accelerator pedal or slows down the vehicle, the answer is yes and the procedure 3500 go to 3504 further. Otherwise, the answer is no and the procedure 3500 continue to the end.

at 3504 determines the procedure 3500 a desired amount of vehicle braking torque. The desired amount of vehicle braking torque may be determined empirically and stored in memory in a function or table indexed about vehicle speed and driver demand torque. Thus, the amount of vehicle braking torque may vary during vehicle deceleration. In one example, the vehicle braking torque is a braking amount provided to the vehicle wheels. The procedure 3500 go to 3506 after the desired amount of vehicle braking torque is determined.

at 3506 stops the procedure 3500 engine rotation and opens the driveline disconnect clutch to save fuel and so that a higher level of driveline braking can be provided via the DISG. A larger amount of driveline braking via the DISG may allow the energy storage device or battery to be recharged at a higher rate. The torque converter clutch (TCC) is set in a locked state so that the DISG can provide additional power during vehicle deceleration. The procedure 3500 go to 3508 after the engine is stopped, the driveline disconnect clutch is opened and the TCC is locked.

at 3508 assess the procedure 3500 Whether the energy storage device or battery state of charge (SOC) is greater than a threshold charge amount or not. If the procedure 3500 judges that the energy storage device SOC is greater than a threshold SOC, the answer is Yes and the method 3500 go to 3512 further. Otherwise, the answer is no and the procedure 3500 go to 3510 further.

at 3510 applies the procedure 3500 Friction brakes on increasing the brake line oil pressure on. The brake line oil pressure can be increased by a pump. The friction brakes exert a force based on the desired vehicle braking torque. In one example, a map or function outputs a brake pipe oil pressure that is estimated to provide the force that provides the desired vehicle braking torque. In some examples the brake pipe pressure may be adjusted in response to the estimated wheel torque or a difference between the desired and actual vehicle speeds, as described herein. The procedure 3500 continues to the end after the friction brakes are adjusted.

at 3512 the procedure occurs 3500 enters a regeneration mode in which the DISG provides negative driveline torque and charges an energy storage device. In particular, the negative torque output by the DISG is adjusted to provide the desired vehicle braking torque, including settings for the transmission gear selection. In one example, the negative DISG torque may be adjusted via adjustment of the DISG charging current. The procedure 3500 go to 3514 after the negative DISG torque is adjusted to provide the desired vehicle braking torque.

at 3514 assess the procedure 3500 whether a positive driveline torque was requested or not. Positive driveline torque may be requested via a driver depressing an accelerator pedal (eg, increasing driver demand torque) or via a controller. If the procedure 3500 judged that a positive driveline torque was requested, the answer is Yes and the method 3500 go to 3516 further. Otherwise, the answer is no and the procedure 3500 returns 3508 back.

at 3516 increases the procedure 3500 slippage of the torque converter clutch (TCC) by reducing the TCC application force. In one example, a duty cycle provided to an electric actuator is reduced to reduce the TCC application force. The TCC slip can be increased to a predetermined extent of empirically determined slip. In one example, TCC slip is based on the amount of desired driveline torque boost. The procedure 3500 go to 3518 continue after the TCC slip is increased.

at 3518 the amount of regenerative braking is reduced by decreasing the negative DISG torque. The regenerative braking torque is reduced toward zero DISG output torque. The procedure 3500 goes after the beginning of the reduction of the regenerative braking torque 3520 further.

at 3520 assess the procedure 3500 Whether the regenerative braking torque is within a predetermined torque range of zero torque (eg, ± 2 Nm) or not. In one example, the regenerative braking torque may be estimated based on the DISG charging current. If the procedure 3500 judges that the regenerative braking torque is within a predetermined torque range of zero torque, the answer is Yes and the method 3500 go to 3522 further. Otherwise, the answer is no and the procedure 3500 returns 3518 back, where the regenerative braking is further reduced.

at 3522 goes the procedure 3500 from operating the DISG in the torque control mode to operate the DISG in the speed control mode. The DISG speed is set to a speed that is a speed that is a predetermined speed greater than the torque converter turbine speed. Since the DISG is coupled to the torque converter impeller, the torque converter impeller speed is greater than the torque converter turbine speed. By setting the DISG speed to a speed greater than the turbine speed, a small positive torque is transmitted through the torque converter to the transmission input shaft. The small positive torque removes the backlash between the gear wheels and the axle gears, so that the impact between the gears can be reduced. The DISG is commanded to the predetermined speed for a predetermined amount of time or until a speed difference between a first gear and a second gear is zero. The speed between the gears can be determined from the transmission input shaft speed and the transmission output shaft speed.

The DISG speed is increased after the DISG has operated at the predetermined speed for a predetermined amount of time or after the speed difference between the gears is zero. In one example, the DISG speed is increased based on a torque converter model. In particular, the torque converter turbine speed and the desired amount of torque for transmission by the torque converter indicate one or more functions outputting a DISG speed that provides the desired amount of torque. The desired amount of torque is based on the driver request torque. The procedure 3500 go to 3524 continue after the DISG speed is set and the gear clearance is removed.

at 3524 the procedure remains 3500 In the speed control mode and the DISG current is set based on an estimated amount of torque for starting the engine. As described previously, when the DISG is in the speed control mode, the current supplied to the DISG is set based on an error between a desired DISG speed and an actual DISG speed. In addition, at 3524 the DISG flow is increased in response to the closing of the driveline disconnect clutch to rotate and start the engine. In one example, an increase in the DISG current is based on a driveline disconnect clutch transfer function that outputs a torque amount based on the application force applied to the driveline disconnect clutch. For example, if the transfer function indicates that the driveline disconnect clutch is transmitting 25 Nm at the current application force, the DISG current is increased to a level that provides an additional 25 Nm of positive torque. The driveline disconnect clutch application force may follow an empirically determined curve stored in the controller memory. In this manner, an open-loop current is supplied to the DISG based on the driveline disconnect clutch application force such that the DISG speed is less varied and so that the closed-loop DISG speed controller can provide less speed correction. The procedure 3500 go to 3526 after the DISG speed and DISG torque are set.

at 3526 starts the procedure 3500 the engine. The engine is started by supplying spark and fuel to the engine as the engine rotates. The engine is accelerated to the DISG speed and then the driveline disconnect clutch is closed. The engine torque and / or the DISG torque are delivered to the driveline after the driveline disconnect clutch is closed. The DISG also transitions from the speed control mode to the torque control mode after the driveline disconnect clutch is closed.

Regarding 36 FIG. 10 is an example sequence for reducing the gear play impact of a driveline according to the method of FIG 35 shown. The sequence of 36 can through the system of 1 - 3 to be provided.

The first diagram from the top of 36 represents the engine speed as a function of time. The Y-axis represents the engine speed and the engine speed increases in the direction of the Y-axis arrow. The X-axis represents the time and the time increases from the left side of the figure to the right side of the figure. The horizontal line 3602 represents the speed of a torque converter impeller during the present sequence.

The second diagram from the top of 36 represents pedal positions (eg accelerator pedal 3606 (Driver request torque) and brake pedal 3604 Torque as a function of time. The Y-axis represents the pedal position and the pedal position increases in the direction of the Y-axis arrow. The X-axis represents the time and the time increases from the left side of the figure to the right side of the figure.

The third diagram from the top of 36 represents the torque converter clutch capacity (TCC) as a function of time. The Y axis represents the TCC capacity and the TCC capacity increases in the direction of the Y axis arrow. The X-axis represents the time and the time increases from the left side of the figure to the right side of the figure.

The fourth diagram from the top of 36 represents the driveline disconnect clutch state as a function of time. The Y axis represents the driveline disconnect clutch state and the driveline disconnect clutch state is fully applied when the curve is at a higher level near the Y axis arrow. The driveline disconnect clutch is released when the driveline disconnect clutch state is near the X axis. The driveline disconnect application pressure increases as the driveline disconnect clutch condition increases. Further, the amount of torque transmitted via the driveline disconnect clutch increases as the driveline disconnect clutch state curve level increases. The X-axis represents the time and the time increases from the left side of the figure to the right side of the figure.

The fifth diagram from the top of 36 represents the torque of the driveline integrated starter / generator (DISG) as a function of time. The Y axis represents the DISG torque and the DISG torque increases in the direction of the Y axis arrow. The X-axis represents the time and the time increases from the left side of the figure to the right side of the figure.

The sixth diagram from the top of 36 represents the transmission torque at the transmission input shaft as a function of time. The Y axis represents the transmission input shaft torque and the transmission input shaft torque increases in the direction of the Y axis arrow. The X-axis represents the time and the time increases from the left side of the figure to the right side of the figure.

36 12 shows an example operation of an engine restart with modulated torque converter clutch operation to control the transition through the transmission gear play range (eg, zero torque through the transmission) while maintaining the transmission gear. An example includes a method in which the driveline disconnect clutch is engaged in accelerator pedaling (e.g. Down of the accelerator pedal) is engaged and in which the DISG the engine to at least the cranking speed (eg., 250 min ^-1) rotates. The engine fueling and combustion provide a torque to accelerate the engine while engine speed continues to increase above the DISG torque (as opposed to starting the starter motor type). Such operation provides a fast engine torque for driving the vehicle. However, since such a rapid increase in torque can cause rattling by the gear play zone, the torque converter clutch is at least partially opened and selectively modulated to control the transition through the gear play zone and reduce the rate of increase of wheel torque until after passing through the gear play zone. Additionally, the DISG output torque may be adjusted to control the driveline output torque during the transition through the gear play zone.

Additional details of the adjustments made with respect to the cog-wheel traversal that can be used in the above-described game traversal control will now be described. As discussed herein, the engine may be shut down and the driveline disconnect clutch opened when the vehicle comes to a stop, stops, or moves / drives when the torque from the DISG is sufficient to accelerate the vehicle and meet the requested torque. to overcome the road load as shown at time T ₈₀ .

In particular, during events when the driver is not requesting driveline torque (eg, accelerator pedal events) and the engine is not rotating, the DISG may be operated as a generator, providing regeneration instead of or in addition to wheel braking, as by one Driver requested by pressing the brake pedal. In this way, the DISG replaces the driveline braking that would have been present if the engine were turning. The DISG recharges the battery or provides electrical power to accessory devices depending on the battery SOC. If the driver then requests additional output by pedaling the accelerator pedal, the engine may be restarted to supplement and / or replace the DISG output torque. Such transitions include traversing the transmission gear range (eg, in the transmission or in the transmission axis drive unit and / or in the rear transmission differential). Specifically, as previously stated herein, when the driver steps on the accelerator pedal during driveline braking, a positive DISG and engine torque is applied to the driveline and the driveline undergoes torque reversal (eg, a transition from negative to positive torque). The torque reversal causes the driveline to traverse the play zone (eg, the tooth-to-tooth gear gap in the rear differential).

At time T ₈₁ , the brake pedal is released by the driver and the TCC capacity is reduced as indicated by reducing the TCC capacity curve. Further, the negative DISG torque is reduced toward zero torque in response to requiring less driveline braking due to the brake pedal being released. The transmission input torque also decreases in response to the DISG torque decrease.

At time T ₈₂ , the driver depresses the accelerator pedal, requesting an increase in positive driveline torque. Shortly afterwards, the DISG torque changes from negative to positive and the TCC capacity is reduced by increasing the TCC slip. The driveline disconnect clutch also begins to close in response to the increase in accelerator pedal position. Closing the driveline disconnect clutch begins to accelerate the prime mover. The transmission input shaft torque is gradually reduced from a small negative torque toward a zero torque. Between time T ₈₂ and time T ₈₃ , the TCC capacitance is reduced in response to an increase in a difference between a rotational speed of a first gear tooth and a second gear tooth. The speed difference between the gear teeth results from the driveline torque reversal.

At time T ₈₃ , the speed difference from gear tooth to gear tooth between the gears is at its highest level and then begins to decrease as gear play is reduced. The TCC capacity is increased in response to the gear tooth speed difference between the gears decreasing. The DISG torque is also increased in response to the speed difference between the gear teeth decreasing, so that the clearance can be reduced. The driveline disconnect clutch condition continues to increase, indicating that an amount of torque that can transfer the driveline disconnect clutch is increasing. The accelerator pedal position and the vehicle speed continue to increase.

At time T ₈₄ , the engine speed reaches the torque converter impeller speed (same as the DISG speed). The TCC capacity and the driveline disconnect clutch become also increases in response to the engine speed reaching the torque converter impeller speed. By waiting until the engine speed equals the torque converter impeller speed to completely close the driveline disconnect clutch, it may be possible to reduce torque disturbances in the driveline. The torque at the transmission input shaft transitions from a negative torque to a positive torque in response to the driveline torque increasing. The DISG torque is also increased at a time after the transmission input shaft torque transitions to a positive torque in response to the driveline disconnect clutch fully closing.

The example method of this sequence recognizes several apparently disjoint pieces of information, including (1) the engine and DISG torque are additive when the driveline disconnect clutch 236 closed is; (2) due to housing constraints, particularly associated with driveline length and driveline diameter limits, the torque capacity of the DISG is usually significantly lower than the maximum engine torque; (3) the DISG torque is a function of the DISG speed, which is equal to engine speed when the clutch is fully closed; and (4) the DISC torque is relatively constant up to a threshold rotor speed of about 1000 ± 100 min ^-1, and then the DISC torque is inversely proportional to the DISC-speed, which is referred to as the range at constant power until friction cause eddy current or other losses, the torque quickly with increasing rotor speed at a higher threshold speed (eg., about 3000 ± 500 min ^-1) decreases.

Thus, when the powertrain is operating in a regenerative braking mode during a closed pedal event (eg, the accelerator pedal is not applied) with the engine off, and then the driver depressing the accelerator pedal. The engine may remain off when the DISG is able to provide the desired torque. Then the driveline disconnect clutch can remain open and the DISG can be quickly transitioned to near-zero torque. The DISG operates in a speed control mode and progresses slowly through the gear play zone. The DISG rapidly increases the output torque after passing through the gear play area to provide the desired torque. In this manner, audible noise and torque pulses through a driveline during a driveline torque transition may be reduced from a negative torque to a positive torque.

Consequently, the methods and systems of 1 - 3 and 35 - 36 operating a powertrain, comprising: stopping rotation of an engine and providing regenerative braking via a driveline; Transitioning from regenerative braking to providing positive torque to the driveline; and operating a driveline integrated starter / generator in a speed control mode during the transition. The method includes where the driveline integrated starter / generator is operated in a torque control mode before and after operating the driveline integrated starter / generator in the speed control mode. The method includes where the driveline integrated starter / generator is set to a speed based on a speed of a torque converter turbine wheel.

In one example, the method further comprises opening a driveline disconnect clutch when the engine is stopped. The method further includes closing a driveline disconnect clutch to start the engine after operating the driveline integrated starter / generator in the speed control mode. The method includes where the regenerative braking is provided when a state of charge of an energy storage device is less than a threshold charge. The method further includes increasing the slip of a torque converter clutch during the transition from regenerative braking to providing positive torque to the driveline.

The methods and systems of 1 - 3 and 35 - 36 provide for operating a powertrain, comprising: stopping the rotation of an engine and providing regenerative braking via a driveline integrated starter / generator; Transferring the driveline integrated starter / generator from providing the regenerative braking to provide positive torque to the driveline; and adjusting the slip of a torque converter clutch in response to the transition from providing regenerative braking to providing positive torque to the driveline. It further comprises operating the driveline integrated starter / generator in a speed control mode during transfer of the driveline integrated starter / generator from providing the regenerative braking to providing positive torque to the driveline.

In one example, the method includes where the driveline integrated starter / Generator is operated at a speed which is a predetermined speed which is greater than a torque converter turbine speed. The method further includes increasing the speed in response to a reduction in gear play. The method includes where adjusting the slip of the torque converter comprises increasing the torque converter slip. The method includes where transferring the driveline integrated starter / generator from providing the regenerative braking to providing positive torque to the driveline occurs in response to an increasing torque request. The method further includes starting the engine via closing the driveline disconnect clutch while adjusting the slip of the torque converter clutch.

The methods and systems of 1 - 3 and 35 - 36 also provide a vehicle system comprising: an engine; an electric machine; a driveline disconnect clutch disposed in a driveline between the engine and the electric machine; a gearbox; a torque converter disposed in the driveline between the electric machine and the transmission; and a control unit having executable instructions stored in a nonvolatile memory for reducing gear play in the transmission via operating the electric machine in a speed control mode and adjusting a rotational speed of the electric machine. The vehicle system further includes a torque converter clutch and additional executable instructions for grinding the torque converter clutch when the electric machine is operating in the speed control mode.

In some examples, the vehicle system further includes additional executable instructions for operating the electric machine at a predetermined speed that is greater than a rotational speed of a turbine wheel of the torque converter. The vehicle system further includes additional executable instructions for increasing a speed of the electric machine after operating the electric machine at the predetermined speed. The vehicle system further includes additional executable instructions for providing the driveline braking torque via the electric machine. The vehicle system further includes additional executable instructions for reducing driveline braking torque in the direction of zero torque prior to operating the electric machine in the speed control mode.

Regarding 37 An example method for entering a sail mode of driveline operation is shown. The procedure of 37 can as executable instructions in the non-volatile memory of the control unit 12 in 1 - 3 be saved.

In one example, the sailing mode may be characterized as combustion of an air / fuel mixture in the engine while the driveline disconnect clutch is open, such that the engine has substantially no torque (eg, less than ± 5 Nm) to the DISG, torque converter, and Transmission supplies. The sailing mode may include a sailing idle speed that is a lower speed than a base idle speed with which the engine is operating as if the engine is coupled to the driveline via a closed driveline disconnect clutch. The idle speed in sail mode is lower, so fuel can be saved in sail mode. Further, the spark timing in the sailing mode may be more advanced than the spark timing when the engine is operating at the base idle speed and the driveline disconnect clutch is closed. The base idle speed may be described as engine idle speed when the engine is warm and no accessory loads are applied to the engine and when the prime mover is coupled to the DISG via the driveline disconnect clutch. The engine may be operated at a lower engine speed and with more spark advance in the sail mode than in conditions where the base idle speed is used because less reserve torque may be required to counteract transient loads that may be applied to the driveline.

at 3702 determines the procedure 3700 Operating conditions. The operating conditions may include, but are not limited to, the driveline torque request, the driveline disconnect clutch state, the engine speed, the vehicle speed, the DISG torque, and the battery state of charge. The procedure 3700 go to 3704 continue after the operating conditions are determined.

at 3704 assess the procedure 3700 whether or not the desired driveline torque is greater than a threshold amount of torque that may be delivered to the driveline via the DISG. The threshold torque amount may be slightly smaller (eg, 10% less) than the DISG rated torque. In one example, an available DISG torque amount may be estimated from empirically determined values stored in a table indexed by the DISG speed and the DISG temperature. The table outputs a maximum or available amount of torque that can be delivered by the DISG to the driveline. In In other examples, the available or threshold DISG torque is less than the maximum DISG torque so that the engine may be maintained in the sailing mode if the desired driveline torque approaches the maximum DISG torque. Further, the threshold DISG torque may be increased in response to operating conditions, such as, for example, For example, increase or decrease the DISG temperature. The procedure 3700 compares the output from the table with the desired driveline torque amount. If the procedure 3700 judges that the desired driveline torque is greater than the threshold DISG torque, the answer is Yes and the method 3700 go to 3706 further. Otherwise, the answer is no and the procedure 3700 go to 3716 further.

at 3706 closes the procedure 3700 the driveline disconnect clutch to turn and start the engine. The driveline disconnect clutch may be closed in accordance with a predetermined closing curve stored in the memory. Alternatively, the engine may be started via a starter other than the DISG and the driveline disconnect clutch is closed after the engine is accelerated to the speed of the DISG. The torque converter clutch slip may also be increased to reduce driveline torque disturbances in response to the desired torque. The procedure 3700 go to 3708 after the driveline disconnect clutch begins to close.

at 3708 provides the procedure 3700 Fuel to the engine and the engine is started when it does not burn an air / fuel mixture. The fuel and spark are supplied to the engine cylinders to facilitate combustion within the engine. The procedure 3700 go to 3710 continue after the engine rotation starts.

at 3710 assess the procedure 3700 Whether the state of charge of the energy storage device (eg, battery) is greater than a threshold amount or not. In one example, the battery state of charge may be estimated from the battery voltage. If the procedure 3700 judges that the battery state of charge is greater than a threshold amount, the answer is Yes and the method 3700 go to 3714 further. Otherwise, the answer is no and the procedure 3700 go to 3712 further.

at 3714 operates the procedure 3700 the engine and DISG to provide the desired amount of driveline torque. The fraction of torque provided by each of the engine and the DISG may vary depending on the operating conditions. For example, if the battery state of charge is low, a greater portion of the driveline torque may be provided by the engine rather than the DISG. The amount of torque delivered by the engine to the driveline may be determined according to the U.S. Patent No. 7,066,121 estimated in all respects. The amount of torque delivered by the DISG to the driveline may be estimated from an empirically determined table indexed via the DISG current and DISG speed. The procedure 3700 continues to the end after the torque is delivered to the driveline via the engine and DISG.

at 3712 operates the procedure 3700 the engine without operating the DISG to deliver the desired torque to the driveline. Further, in some examples, the DISG may be transitioned to a battery charging mode in which mechanical energy from the engine is converted to electrical energy via the DISG and stored in an electrical energy storage device. In one example, the engine air amount and the engine fuel amount are adjusted to provide the desired amount of driveline torque. For example, as the desired amount of driveline torque is increased, the amount of air and fuel supplied to the engine cylinders is increased. The procedure 3700 Goes to the end after the engine operation is set to deliver a desired amount of torque to the driveline.

at 3716 assess the procedure 3700 Whether the engine is running and burning air / fuel mixtures in the engine cylinders or not. In one example, it may be determined that the engine is combusting air / fuel mixtures as the engine torque increases, as may be certified by increasing engine speed. If the procedure 3700 judged that the engine is burning and running air / fuel mixtures, the answer is yes and the procedure 3700 go to 3730 further. Otherwise, the answer is no and the procedure 3700 go to 3718 further.

at 3718 assess the procedure 3700 Whether the battery state of charge is greater than a threshold amount or not. In one example, the battery voltage is a basis for estimating the battery state of charge. If the procedure 3700 judges that the battery state of charge is greater than a threshold amount, the answer is Yes and the method 3700 go to 3724 further. Otherwise, the answer is no and the procedure 3700 go to 3720 further.

at 3724 provides the procedure 3700 the desired driveline torque across the DISG and without torque from the engine. Power is supplied to the DISG on the basis of a table stored in memory that outputs a DISG current amount based on a desired DISG torque and the DISG temperature. The values in the table can be determined empirically. The procedure 3700 continues to the end after the DISG torque is delivered to the driveline.

at 3720 turns and starts the procedure 3700 the engine. The engine can be rotated via a starter motor other than the DISG or through the DISG. When the engine is rotated by the DISG, the driveline disconnect clutch is closed to transfer the torque from the DISG to the engine. The engine is started by supplying fuel and a spark to the engine cylinders after the engine reaches the cranking speed. The engine cranking speed may be changed for different operating conditions. For example, when the engine is rotated by the starter motor other than the DISC, the cranking speed is a speed which is less than 250 min ^-1. However, when the engine is turned by the DISC, the cranking speed can be a speed that is less than 1200 min ^-1. The procedure 3700 go to 3722 continue after the engine is turned and started.

at 3722 the procedure begins 3700 supplying at least a portion of the engine torque to the vehicle wheels and begins charging the battery to increase the battery state of charge. The driveline disconnect clutch is closed when the engine supplies torque to the vehicle wheels and charges the battery. Further, the engine output torque is adjusted to provide the desired driveline torque quantity. The engine output torque may be increased or decreased by adjusting the cylinder air amount and the cylinder fuel amount. The procedure 3700 Goes to the end after at least part of the engine output is delivered to the vehicle wheels.

at 3730 assess the procedure 3700 whether or not there are selected conditions for entering the sailing mode. In one example, sailing mode may be entered when the engine temperature is greater than a threshold temperature. Furthermore, other operating conditions such. B. the engine speed and the requested torque are evaluated to determine whether the sailing mode can be entered. In some examples, sailing mode may also be entered when the battery state of charge is less than a threshold state of charge.

For example, sailing mode may also be entered when the catalyst temperature is below a threshold and other conditions. The controller may choose to idle the engine instead of turning off the engine since emissions may increase when the engine is started with cold catalysts. The control unit may choose to idle the engine instead of closing the driveline disconnect clutch and operating the engine to generate torque when the battery SOC is high and / or the current operating point would require the engine to run on an engine low fuel efficient point works.

The sailing mode can also be entered when the fuel vapor tank requires a purge. The control unit may choose to idle the engine instead of shutting off the engine, as it is planned that the fuel vapor purge will expire. The control unit may also choose to idle the engine instead of closing the driveline disconnect clutch and operating the engine to generate torque when the battery SOC is high and / or the current operating point would require the engine works on a low fuel efficient point.

Sailing mode may also be entered if an increase in brake booster vacuum is desired. The control unit may choose to idle the engine instead of turning off the engine because a vacuum is desired, and the engine is operated to provide the vacuum.

Sailing mode can be entered when engine coolant temperature (ECT) is low. The controller may choose to idle the engine instead of turning off the engine since the ECT is low.

Sailing mode may be entered when a faster response to accelerator pedal kick is desired for the sportsman mode. The control unit may choose to idle the engine instead of turning off the engine because the drive mode has been determined or selected as the sport mode. Reaction to the driver's accelerator pedal kicks is faster with the engine in skimming than when the engine is stopped.

If the procedure 3700 judged that there are selected conditions to allow entry into sailing mode, the answer is yes and the method 3700 go to 3732 further. Otherwise, the answer is no and the procedure 3700 go to 3718 further.

at 3732 opens the procedure 3700 the driveline disconnect clutch. The driveline disconnect clutch is opened so that any torque generated by the engine is not provided to the remainder of the driveline, including the DISG, the torque converter, and the transmission. Opening the driveline disconnect clutch allows the engine to operate in a more efficient operating condition than if the engine were coupled to the DISG, the torque converter, and the transmission because the engine can be operated with a smaller torque reserve. In one example, an engine torque reserve may be designated as the amount of torque available from the engine when the engine is operating at a particular speed and air amount without providing the total amount of available engine torque.

An engine can generate, for example, 100 Nm of torque at 1200 min ^-1 and at a prescribed cylinder air amount. However, the amount of engine ^torque available at 1200 rpm when the engine draws the prescribed cylinder air amount may be 125 Nm. The difference of 25 Nm can be explained by the engine operating at a spark timing delayed from the MBT spark timing. The 25 Nm represents a torque reserve that can be held to compensate for torque disturbances that may be delivered to the engine. However, the 25Nm also represents a loss of engine efficiency due to spark retard. The engine may be operated with a smaller torque reserve when the driveline disconnect clutch is open because fewer torque disturbances can be applied to the engine via the driveline. The procedure 3700 go to 3734 after the driveline disconnect clutch is opened.

at 3734 assess the procedure 3700 whether the desired driveline torque is within a threshold range of a DISG torque threshold or not. The DISG torque threshold may represent a maximum amount of torque available from the DISG or an amount of torque less than the total available DISG torque. If the procedure 3700 judges that the desired driveline torque is within a threshold torque range of the DISG torque threshold, the answer is Yes and the method 3700 go to 3736 further. Otherwise, the answer is no and the procedure 3700 go to 3738 further.

at 3736 operates the procedure 3700 the engine with a sailing idle speed and adjusts the engine spark timing and valve timing to improve engine efficiency and fuel economy. The desired driveline torque is provided by the DISG when the driveline disconnect clutch is in an open state. The sail idling speed may be lower than the base idle speed when the engine is coupled to the DISG and the transmission. Further, the spark timing while the engine is operating at the sail idling speed may be advanced as compared to when the engine is operated at the base idle speed. The base idle speed may be applied when the desired driveline torque is low and when the prime mover is coupled to the remainder of the driveline via a closed driveline disconnect clutch. The engine valve timing may be adjusted to operate the engine with improved volume efficiency. In one example, the valve timing is adjusted such that the intake valve timing closes late to increase the engine intake manifold pressure while the cylinder air charge is relatively low. The procedure 3700 Continue to the end after the engine is on 3736 enters the sailing mode.

at 3738 assess the procedure 3700 whether a starter other than the DISG is present in the system or not. In some examples, the method may 3700 judge that a starter other than the DISG is absent if the starter other than the DISG is deteriorated. The procedure 3700 can also judge that a starter other than the DISG is present if a starter present bit is in memory. If the procedure 3700 judged that there is a starter other than the DISG, the answer is yes and the method 3700 go to 3740 further. Otherwise, the answer is no and the procedure 3700 go to 3740 further.

at 3740 stops the procedure 3700 the engine rotation and desired driveline torque is delivered via the DISG. The engine rotation is stopped by stopping the fuel flow and the spark to the engine cylinders. The engine is at 3740 stopped, so that additional fuel can be saved and because the engine restarted without any torque from the DISG can be. In this way, a larger amount of DISG torque may be delivered to the driveline as a portion of the available DISG torque need not be kept in reserve to restart the engine. The procedure 3700 Continue to the end after the engine is stopped.

at 3742 assess the procedure 3700 Whether the DISC output torque is within a threshold range of the engine starting torque (z. B. an amount of torque to rotate the engine from a zero speed to a cranking speed of less than 250 min ^-1) or not. For example, when the engine cranking torque is 40 Nm and a threshold range is 5 Nm, the DISG is within the threshold range of the engine cranking torque when the DISG output torque is 35.5 Nm. If the procedure 3700 judges that the DISG output torque is within a threshold torque range of the engine cranking torque, the answer is Yes and the method 3700 go to 3744 further. Otherwise, the answer is no and the procedure 3700 go to 3746 further.

at 3746 stops the procedure 3700 the engine rotation and provides the desired driveline torque via the DISG. The engine is stopped to further reduce fuel consumption. Since the DISG has a sufficient amount of torque available to restart the engine, the engine may be stopped. If the desired driveline torque increases while the engine is stopped, the engine may be restarted via the DISG before the DISG has insufficient output torque capacity to start the engine and provide the desired driveline torque. However, in some examples, the engine may continue idling at the sailing mode idle speed when the battery state of charge is less than a threshold and the vehicle requires additional negative pressure, fuel vapor purge, catalyst temperature, or engine temperature. The procedure 3700 Continue to the end after the engine is stopped.

at 3744 operates the procedure 3700 the engine with the sail idling speed, sets the spark timing, the valve timing, and provides the driveline torque via the DISG, as at 3736 described. The procedure 3700 Continue to the end after the engine enters sail mode.

It should be noted that when a driver reduces driver demand torque (eg, releases the accelerator pedal or decreases accelerator pedal input), the driveline follows the method of FIG 37 can work. The torque may be provided by an engine to a driveline coupled to the vehicle wheels when the driver demand torque is greater than a DISG threshold torque. The engine speed may be reduced to a sailing mode idle speed and the engine decoupled from the driveline in response to decreasing driver demand torque. The DISG may enter a regeneration mode that provides charge to a battery and provides a constant rate of deceleration for the vehicle. In one example, the DISG threshold torque is greater than 75% of a nominal DISG torque.

It should be noted that when a driver increases a driver request torque (eg, steps on the accelerator pedal or increases an accelerator pedal input), the driveline follows the method of FIG 37 can work. The engine may accelerate from a coasting idle speed to the DISG speed in response to increasing driver demand torque. The driveline disconnect clutch may be closed in response to reaching engine speed the DISG speed.

It should be noted that, when a driver increases a driver request torque (eg, accelerator pedal or increases accelerator pedal input) during vehicle launch, the driveline follows the method of FIG 37 can work. The DISG torque is delivered to the vehicle driveline in response to driver demand torque while the engine is not rotating. The engine may be started and idled at a sailing mode idling speed without providing engine torque to the driveline in response to the driver request torque being within a threshold engine cranking torque range (eg, when the DISG torque is greater than 75% of engine cranking torque). The engine can be accelerated in a speed control mode, so that it is substantially of the DISC speed (z. B. ± 50 min ^-1), and the drive line clutch can be closed when the engine speed is substantially the DISC-speed (eg. B. ± 50 min ^-1 ) corresponds. In some examples, engine speed may track the DISG speed when the desired torque is between engine cranking torque and a threshold DISG torque (eg, torque between 75% of DISG rated torque and DISG rated torque).

Furthermore, the engine at 3736 and 3744 in a speed control mode to track the DISG speed when the desired driveline torque is within a predetermined torque range of the DISG threshold torque. By following the DISG speed, the driveline disconnect clutch can be closed earlier to improve the driveline response.

In this way, the method of 37 an efficient engine operating mode that can reduce engine fuel consumption as compared to the engine operating at the base idle speed. Furthermore, the method of 37 stopping the engine if additional fuel can be saved. In addition, the method maintains the driveline torque response even when the engine can be operated or stopped more efficiently.

Regarding 38 For example, an example method for exiting a sail mode of driveline operation is shown. The procedure of 38 can as executable instructions in the non-volatile memory of the control unit 12 in 1 - 3 be saved.

at 3802 determines the procedure 3800 Operating conditions. The operating conditions may include, but are not limited to, the driveline torque request, the driveline disconnect clutch state, the engine speed, the vehicle speed, the DISG torque, and the battery state of charge. The procedure 3800 go to 3804 continue after the operating conditions are determined.

at 3804 assess the procedure 3800 whether the engine is in sail mode at the sail idle speed and whether the driveline disconnect clutch is open or not. The engine operating mode and the driveline disconnect clutch operating condition may be determined by performing a query on one or more bits or flags stored in memory. If the procedure 3800 judging that the engine is not in sailing mode, the answer is no and the method 3800 continue to the end. If the procedure 3800 judges that the engine is in the sailing mode and the driveline disconnect clutch is open, the answer is Yes and the method 3800 go to 3806 further.

at 3806 assess the procedure 3800 Whether a desired driveline torque is greater than a DISG threshold torque or not. The DISG threshold torque may be equal to or less than the available amount of DISG torque. If the procedure 3800 judges that the desired driveline torque is greater than the DISG threshold torque, the answer is Yes and the method 3800 go to 3808 further. Otherwise, the answer is no and the procedure 3800 continue to the end.

at 3808 increases the procedure 3800 the engine speed from the sail idle speed to a speed that is synchronous with the DISG speed via increasing an engine air amount and engine fuel amount (eg, the amounts of air and fuel supplied to the engine cylinders). Further, the spark timing may be delayed away from the MBT spark timing as the engine air amount and fuel amount are increased. The procedure 3800 go to 3810 after the engine air amount and fuel amount are increased, so that the engine torque is increased and so that the engine is accelerated to the speed of the DISG.

at 3810 increases the procedure 3800 a degree of slip of the torque converter clutch (TCC). The torque converter clutch slip may be increased via decreasing the torque converter clutch application force. By increasing TCC slip, driveline torque disturbances can be reduced. The procedure 3800 go to 3812 continue after the TCC slip is increased.

at 3812 closes the procedure 3800 the driveline disconnect clutch. The driveline disconnect clutch may be closed when the engine speed reaches the DISG speed and after the engine speed has set at the DISG speed for a predetermined amount of time. The procedure 3800 go to 3814 after the driveline disconnect clutch is closed.

at 3814 increases the procedure 3800 engine torque via increasing engine air and fuel levels. Additionally, the DISG torque may be increased to boost the engine torque so that the desired driveline torque may be provided. The procedure 3800 continues to end after the engine torque and DISG torque are adjusted to provide the desired driveline torque.

In this way, the method of 38 transitioning from the sailing mode in response to accelerator pedal depression (eg, depressing an accelerator pedal to a higher torque request), the DISG providing the torque to the wheels and the engine idling. For example, the driver steps on the accelerator pedal and the new torque demand increases rapidly across the entire torque capacity of the DISG. The engine accelerates in the speed control mode toward the DISG speed, the TCC may be opened to allow for torque multiplication and isolation of the driveline, and the driveline disconnect clutch may be closed to bring the engine up to speed very quickly. The engine goes into the torque control, after the engine reaches substantially the DISG speed (z. B. ± 100 min ^-1). Subsequently, the engine and the DISG may provide the desired torque.

Regarding 39 FIG. 10 is an example sequence for operating a driveline that includes a sailing mode according to the methods of FIG 37 and 38 shown. The sequence of 39 can through the system of 1 - 3 to be provided.

The first diagram from the top of 39 represents the vehicle speed as a function of time. The y-axis represents the vehicle speed and the vehicle speed increases in the direction of the y-axis arrow. The X-axis represents the time and the time increases from the left side of the figure to the right side of the figure.

The second diagram from the top of 39 The desired driveline torque may be a torque at the vehicle wheels, a torque converter impeller, a torque converter turbine, or at a driveline disconnect clutch. The Y axis represents the desired driveline torque, and the desired driveline torque increases in the direction of the Y axis arrow. The X-axis represents the time and the time increases from the left side of the figure to the right side of the figure. The horizontal line 3902 represents a threshold driveline torque (eg, torque within a prescribed torque of nominal or maximum DISG torque) for which a DISG has the ability to deliver it to the driveline. The horizontal line 3904 represents a threshold amount of torque (z. B. a torque within a prescribed torque of the engine starting torque) is capable of supplying the DISC while it has a capacity for starting the engine to the cranking speed (eg., 250 min ^-1).

The third diagram from the top of 39 represents the driveline disconnect clutch state as a function of time. The Y axis represents the driveline disconnect state and the driveline disconnect clutch is closed when the driveline disconnect clutch state curve is at a higher level near the Y axis arrow. The driveline disconnect clutch is open when the driveline disconnect clutch state is at a lower level near the X axis. The X-axis represents the time and the time increases from the left side of the figure to the right side of the figure.

The fourth diagram from the top of 39 represents the engine state as a function of time. The Y axis represents the engine state and the engine rotates when the engine state curve is at a higher level near the Y axis arrow. The engine will not spin when the engine state curve is near the X axis. The X-axis represents the time and the time increases from the left side of the figure to the right side of the figure.

The fifth diagram from the top of 39 represents the energy storage device or battery state of charge (SOC) as a function of time. The Y axis represents the battery SOC and the battery SOC increases in the direction of the Y axis arrow. The X-axis represents the time and the time increases from the left side of the figure to the right side of the figure. The horizontal line 3906 represents a threshold amount of battery charge that is desired. An amount of charge over 3906 may be desired to reduce the possibility of battery degradation.

At time T ₈₅ , the vehicle speed is zero, the engine is stopped, the driveline disconnect clutch is open, the battery state of charge is at an intermediate level that is greater than the level 3906 , These conditions may represent conditions when a vehicle is parked or stopped at a traffic light.

At time T ₈₆ , the desired driveline torque increases in response to increasing driver demand torque, as determined by an accelerator pedal (not shown). The engine remains in an off state and the driveline disconnect clutch remains closed. Vehicle speed begins to increase as a driveline integrated starter / generator (DISG) (not shown) begins to deliver positive torque to the vehicle driveline. The battery SOC begins to fall off because Battery charge is used to power the vehicle.

Between time T ₈₆ and time T ₈₇ , the desired driveline torque exceeds the torque level 3904 in response to a driver request torque. As a result, the engine is rotated and started; however, the driveline disconnect clutch remains open. The engine can be started via a different starter than the DISG. The vehicle speed continues to increase and the battery SOC continues to decrease.

At time T ₈₇ , the desired driveline torque exceeds the torque level 3902 in response to the driver request torque. Shortly thereafter, the driveline disconnect clutch becomes the threshold torque level in response to the driveline torque 3902 exceeds, closed. By closing the driveline disconnect clutch, driveline torque may be increased via increasing engine torque. Closing the driveline disconnect clutch couples the prime mover to the DISG and the remaining driveline. The engine remains running and the engine torque is increased so that the desired driveline torque may be provided by the DISG and the engine. The battery SOC continues to decrease as the DISG provides torque to the driveline.

At time T ₈₈ , the desired driveline torque increases to a level below the threshold torque level in response to the driver input 3902 but it stays above the threshold torque level 3904 , The engine torque is reduced in response to the reduced desired driveline torque. In addition, the driveline disconnect clutch is opened to decouple the engine from the DISG and driveline. The engine continues to burn both air and fuel. The engine speed may be reduced to a sail idle speed that is lower than a base idle speed that the engine rotates with when the engine is coupled to the DISG. In addition, the engine spark timing can be advanced. Reducing engine speed and advancing spark timing can reduce fuel consumption.

At time T ₈₉ , the desired driveline torque is applied a second time by the driver to a level above the threshold torque 3902 elevated. The driveline disconnect clutch becomes the torque threshold in response to the driveline torque 3902 exceeds, closed. The engine torque is then increased and the desired driveline torque is provided via the engine. The DISG enters a generator mode and the battery state of charge is increased over part of the engine torque. The vehicle speed increases as the engine torque is delivered to the driveline.

At the time T ₉₀ the desired powertrain torque increases in response to a reduced from driver request torque. The desired driveline torque increases to a torque below the threshold torque 3904 from. As a result, the driveline disconnect clutch is opened and engine rotation is stopped in response to the low desired driveline torque. In this way, the vehicle fuel consumption can be reduced. The DISG remains in generator mode and increases the battery charge when the vehicle slows down.

At time T ₉₁ , the desired driveline torque is increased in response to a driver request torque. The desired driveline torque will be at a level between the torque threshold 3902 and the torque threshold 3904 elevated. Since the desired driveline torque near the threshold torque 3902 is located, the engine is rotated and started, so that the engine torque can be provided in a reduced amount of time, when the desired driveline torque continues to increase. The vehicle speed is increased by supplying the torque to the DISG. The battery state of charge begins to decrease as the DISG provides torque to the vehicle driveline.

At time T ₉₂ , the desired driveline torque is increased in response to increasing driver demand torque. The desired driveline torque increases to a level greater than the threshold torque 3902 , Shortly thereafter, the driveline disconnect clutch is closed and the engine torque is delivered to the driveline. In this way, the driveline torque may be increased slightly without having to wait for the engine speed to reach a level at which the torque may be delivered to the driveline. The DISG will also be put in the generator mode and the battery SOC will be increased.

At time T ₉₃ , the desired driveline torque increases to a level below the threshold torque level in response to a driver input 3902 but stays above that Threshold torque level 3904 , The engine torque is reduced in response to the reduced desired driveline torque. Further, the driveline disconnect clutch is opened to decouple the engine from the DISG and driveline. The engine continues to burn both air and fuel. The engine speed may be reduced to a sail idle speed. The torque is supplied via the DISG to the driveline, which transitions to a torque mode that outputs a positive torque to the vehicle driveline.

At time _T94 , the battery SOC becomes the level 3906 decreases if the DISG continues to consume cargo. The driveline disconnect clutch is closed in response to the battery SOC and the DISG is transitioned to a generator mode. The engine delivers torque to the driveline and to the DISG. Thus, the driveline disconnect clutch may be opened and closed in response to a desired driveline torque and the battery SOC. Shortly after time T ₉₄ , the desired driveline torque becomes at a level above the torque threshold 3902 elevated. Since the driveline disconnect clutch is already closed, it remains in that state.

At the time T ₉₅ the desired powertrain torque increases in response to a reduced from driver request torque. The desired driveline torque increases to a torque below the threshold torque 3904 from. As a result, the driveline disconnect clutch is opened in response to the low desired driveline torque and engine rotation is stopped. The DISG remains in generator mode and increases the battery charge when the vehicle slows down.

Regarding 40 FIG. 10 is an example sequence for operating a driveline that includes a sailing mode according to the methods of FIG 37 and 38 shown. The sequence of 40 can through the system of 1 - 3 to be provided.

The first diagram from the top of 40 represents the driveline disconnect clutch state as a function of time. The Y axis represents the driveline disconnect clutch state and the driveline disconnect clutch is closed when the driveline disconnect clutch state curve is at a higher level near the Y axis arrow. The X-axis represents the time and the time increases from the left side of the figure to the right side of the figure.

The second diagram from the top of 40 represents the engine speed as a function of time. The Y-axis represents the engine speed and the engine speed increases in the direction of the Y-axis arrow. The X-axis represents the time and the time increases from the left side of the figure to the right side of the figure. The horizontal line 4002 represents a base engine idle speed when the engine is coupled to the DISG via the driveline disconnect clutch. The horizontal line 4004 represents a base engine sail mode idle speed when the engine is combusting air and fuel but is not coupled to the DISG.

The third diagram from the top of 40 represents the DISG torque as a function of time. The Y axis represents the DISG torque and the DISG torque increases in the direction of the Y axis arrow. The X-axis represents the time and the time increases from the left side of the figure to the right side of the figure. The horizontal line 4006 represents an amount of torque that the DISG can deliver to the driveline (eg, a DISG rated torque). The horizontal line 4008 represents an amount of torque that the DISG can deliver to the driveline while it can crank the engine from a zero speed.

The fourth diagram from the top of 40 represents the desired driveline torque as a function of time. The Y-axis represents the desired driveline torque and the desired driveline torque increases in the direction of the Y-axis arrow. In one example, the desired driveline torque is based on driver demand torque as determined by an accelerator pedal. The X-axis represents the time and the time increases from the left side of the figure to the right side of the figure.

The fifth diagram from the top of 40 represents the operating state of a low-power starter (eg, a starter with a lower starting power than the DISG). The Y-axis represents the operating state of the low-power starter and the low-power starter rotates when the state curve of the low-power starter near the Y -Axis-arrow lies. The X-axis represents the time and the time increases from the left side of the figure to the right side of the figure.

At time T ₉₆ , the driveline disconnect clutch is closed and engine speed is at an elevated level. The engine delivers positive torque to the driveline. The DISG torque is at a low level, indicating that the engine has the most torque Drive train delivers. Furthermore, the low-capacity starter does not work.

Between time T ₉₆ and time T ₉₇ , the driveline disconnect clutch is opened in response to a decrease in desired driveline torque and the engine is stopped. The desired driveline torque decreases in response to a decrease in driver demand torque (not shown). The low capacity starter remains off and the DISG torque remains at a lower level.

At time T ₉₇ , the driveline disconnect clutch is partially closed in response to a low battery state of charge (not shown). The DISG torque is briefly increased in response to the driveline disconnect clutch closing. The DISG provides additional torque to the driveline for starting the engine. Shortly thereafter, the engine is started by supplying fuel and a spark to the engine. The DISG torque is reduced after the engine is started, and the DISG torque becomes negative when the DISG enters a generator mode to charge the battery. The engine is cranked without the low-capacity starter via the driveline disconnect clutch and the DISG at a time when the DISG torque is below the threshold 4008 lies.

Between time T ₉₇ and time T ₉₈ , the engine and DISG charge the battery. The engine is stopped after the battery is charged and the DISG begins to deliver positive torque to the driveline. The driveline disconnect clutch is also opened when the engine is stopped. The desired driveline torque is increased shortly after the engine is stopped, in response to increasing driver demand torque. However, the desired driveline torque is not within a threshold range of the torque level 4006 so that the engine is not started.

At time _T98 , the desired driveline torque is increased to a level within a threshold torque range to the torque level 4006 lies. The low capacity starter is engaged and rotates the engine in response to increasing the desired driveline torque. The engine starts shortly thereafter when the spark and fuel are supplied to the engine. The driveline disconnect clutch remains in an open state because the DISG can provide the desired driveline torque without assistance from the engine. The engine operates at the sail idling speed in anticipation of an increased desired driveline torque.

At time T ₉₉ , the desired driveline torque increases to a level below the threshold level 4008 in response to a reduced driver request torque (not shown). The engine is stopped in response to the low desired driveline torque and the low capacity starter remains off. The driveline disconnect clutch also remains in an open condition.

Between time T ₉₉ and time T ₁₀₀ , the desired driveline torque is increased in response to increased driver demand torque. The desired driveline torque is increased to a level less than a threshold torque level 4006 is removed. Therefore, the DISG provides the desired driveline torque without starting the engine. The driveline disconnect clutch remains in an open state.

At time T ₁₀₀ , the desired driveline torque is further increased in response to increased driver demand torque. The low-capacity starter is engaged and the engine is rotated in response to the desired driveline torque being within a threshold level of the torque level 4006 increases. The engine is started by supplying a spark and fuel to the engine in response to the engine rotation. The engine is up to the sailing mode idle speed 4004 accelerated. The DISG continues to deliver a very positive torque to the drivetrain to meet the desired driveline torque. The low-capacity starter is disengaged shortly after the engine is started.

At time T ₁₀₁ , the desired driveline torque is increased to a level greater than the torque level in response to increasing driver demand torque 4006 , The driveline disconnect clutch is closed in response to increasing driver demand torque and engine speed is also increased so that the engine may provide additional torque to boost the DISG torque. The low-capacity starter remains off.

In this manner, the starter, engine, and disconnect clutch may be operated to provide a shorter response time to an increase in desired driveline torque. Furthermore, the low capacity starter can be used in Operating conditions in which the DISG lacks the capacity to start the engine so that the DISG operating range can be extended.

Consequently, the methods and systems of 1 - 3 and 37 - 40 Also, a driveline operating method, comprising: operating an engine and providing engine torque to a driveline that drives a vehicle in response to a desired torque being greater than a threshold torque of a driveline integrated starter / generator; and operating the engine and not providing engine torque to the driveline in response to the desired torque being less than the threshold driveline torque and greater than a threshold engine cranking torque. In this way, a driveline can operate with improved efficiency and provide a shorter torque response time.

In some examples, the method includes where the threshold torque of the driveline integrated starter / generator is a torque within a predetermined torque range of a rated torque of a driveline integrated starter / generator. The method includes where the engine cranking threshold torque is within a predetermined torque range of engine cranking torque. The method includes that the engine starting torque is a torque for rotating the engine by a rotation of zero to a speed of less than 250 min ^-1. The method further includes operating a driveline disconnect clutch in an open state while the engine is operating and no engine torque is being delivered to the driveline. The method includes where the desired torque is based on driver demand torque. The method further includes providing torque to the driveline via a driveline integrated starter / generator while the engine is operating and no engine torque is being delivered to the driveline.

The methods and systems of 1 - 3 and 37 - 40 also provide a powertrain operating method comprising: rotating an engine and providing engine torque to a driveline that drives a vehicle in response to a desired torque being greater than a threshold torque of a driveline integrated starter / generator; Rotating the engine and not providing the engine torque to the driveline in response to the desired torque being less than the driveline threshold torque and greater than an engine cranking threshold torque; and not rotating the engine in response to the desired torque being less than the engine cranking threshold torque. The method further includes rotating and operating the engine in response to a battery state of charge when the desired torque is less than the engine cranking threshold torque.

In one example, the method further comprises rotating the engine from a stopped state in response to the desired torque being greater than the threshold torque of the driveline integrated starter / generator. The method includes where the threshold torque of the driveline integrated starter / generator is less than a predetermined torque away from a rated torque of the driveline integrated starter / generator. The method includes where a driveline disconnect clutch is in a closed state when the engine torque is delivered to the driveline that powers the vehicle. The method includes where a driveline disconnect clutch is in an open state when no engine torque is delivered to the driveline that powers the vehicle. The method includes where a threshold torque of the driveline integrated starter / generator varies with vehicle operating conditions.

The methods and systems of 1 - 3 and 37 - 40 also provide a vehicle system comprising: an engine; a dual mass flywheel having a first side mechanically coupled to the engine; a driveline disconnect clutch having a first side mechanically coupled to a second side of the dual mass flywheel; a driveline integrated starter / generator (DISG) having a first side coupled to a second side of the driveline disconnect clutch; a transmission selectively coupled to the engine via the driveline disconnect clutch; and a controller having executable instructions stored in a nonvolatile memory to idle an engine at a first idle speed while the driveline disconnect clutch is in an open state and executable instructions to idle the engine at a second idle speed operate, wherein the second idle speed is greater than the first idle speed, while the driveline disconnect clutch is in a closed state.

In one example, the vehicle system further includes additional executable instructions for opening and closing the driveline disconnect clutch in response to a desired driveline torque. The vehicle system further includes additional executable instructions for advancing the spark timing and decreasing the engine air amount in response to the engine operating at the first idle speed. The vehicle system further includes additional executable instructions for delaying the spark timing and increasing the engine air amount relative to the spark timing and the engine air amount when the engine is operating at the first idle speed. The vehicle system further includes additional executable instructions for providing engine torque to the transmission in response to a desired torque being greater than a threshold torque of the driveline integrated starter / generator. The vehicle system further includes additional executable instructions to provide no engine torque to the transmission in response to the desired torque being less than a threshold torque of the driveline integrated starter / generator.

The methods and systems of 1 - 3 and 37 - 40 also provide a driveline operating method, comprising: operating an engine at a predetermined skid speed, the skid speed being less than a base engine idle speed; and opening a driveline disconnect clutch while the engine is operating at the predetermined sail idle speed to decouple the engine from the vehicle wheels. The method includes where the engine is operated at the predetermined coasting speed when a desired driveline torque is within a threshold range of a driveline integrated starter / generator (DISG) threshold torque and when the DISG provides torque to the vehicle wheels, and that Vehicle moves while the engine is at the predetermined Segereerlaufdrehzahl. The method includes where the DISG threshold torque is a maximum torque capacity of the DISG.

In some examples, the method further includes advancing the spark timing more than the spark timing at the base engine idle speed. The method further includes leaving the glider racing speed in response to a desired torque exceeding a threshold. The method further includes closing the driveline disconnect clutch in response to the desired torque exceeding the threshold. The method includes where the driveline disconnect clutch is in a driveline disposed between the engine and a driveline integrated starter / generator.

The methods and systems of 1 - 3 and 37 - 40 also provide a powertrain operating method comprising: operating an engine at a predetermined coasting speed in response to an operating condition wherein a driveline integrated starter / generator (DISG) lacks the torque to start an engine from rest, wherein the skid speed is lower is as a base engine idling speed; and opening a driveline disconnect clutch while the engine is operating at the predetermined sail idle speed to decouple the engine from the vehicle wheels. The method further comprises delivering a desired driveline torque to the vehicle wheels via a DISG while the engine is operating at the predetermined sail idle speed.

In one example, the method further comprises leaving the engine at the predetermined sail idle speed in response to a torque request that is greater than a threshold. The method includes disconnecting the engine from the DISG. The method includes disconnecting the engine from a transmission. The method further comprises accelerating the engine to a speed of the DISG prior to closing the driveline disconnect clutch. The method includes where the spark delivered to the engine while the engine is operating at the predetermined sparkle speed is biased more than when the engine is operated at the base idle speed.

The methods and systems of 1 - 3 and 37 - 40 also provide a vehicle system comprising: an engine; a dual mass flywheel (DMF) having a first side mechanically coupled to the engine; a driveline disconnect clutch having a first side mechanically coupled to a second side of the dual mass flywheel; a driveline integrated starter / generator (DISG) having a first side coupled to a second side of the driveline disconnect clutch; a transmission selectively coupled to the engine via the driveline disconnect clutch; and a controller having nonvolatile instructions executable to enter a sailing mode in response to a desired torque.

In one example, the vehicle system further includes additional instructions for entering the sailing mode in response to the desired output torque being within a threshold torque of a DISG torque capacity. The vehicle system further includes additional instructions for entering the sailing mode in response to insufficient available DISG torque to start the engine. The vehicle system further includes additional commands to exit the sailing mode in response to the desired torque being greater than a threshold. The vehicle system further includes additional commands to increase engine speed in response to exiting the sailing mode. The vehicle system further includes additional commands to close the driveline disconnect clutch when engine speed is substantially at the DISG speed.

The methods and systems of 1 - 3 and 37 - 40 also provide a driveline operating method, comprising: providing torque from an engine to a driveline coupled to the wheels; Operating the engine at an idle speed and decoupling the engine from the driveline in response to a reduced driver request torque; and providing a constant vehicle deceleration rate during the reduced driver request torque. In this way, a driveline can save fuel while providing driveline braking and improved torque response.

In some examples, the method further includes opening a driveline disconnect clutch in response to the reduced driver request torque. The method includes where a driveline integrated starter / generator provides negative torque to provide the constant vehicle deceleration rate. The method includes where the idle speed is a first idle speed and the first idle speed is less than a second idle speed, wherein the engine is operated at the second idle speed when the engine is coupled to the driveline. The method includes where the engine is operated at idle speed in response to the reduced driver request torque being less than a threshold torque of the driveline integrated starter / generator. The method includes where the threshold torque of the driveline integrated starter / generator is greater than 75% of a rated torque of the driveline integrated starter / generator. The method includes where the torque delivered by the engine is a positive torque.

The methods and systems of 1 - 3 and 37 - 40 also provide a driveline operating method, comprising: providing torque from an engine to a driveline coupled to the wheels; Operating the engine at an idle speed and decoupling the engine from the driveline in response to a reduced driver request torque; Providing a constant vehicle deceleration rate at the reduced driver request torque; and accelerating the engine to a speed in response to an increase in driver demand torque after operating the engine at idle speed. The method includes where the speed is a speed of a driveline integrated starter / generator.

In some examples, the method further includes closing a driveline disconnect clutch in response to the speed reaching the speed of the driveline integrated starter / generator. The method includes providing the constant vehicle deceleration via a driveline integrated starter / generator. The method includes where the driveline integrated starter / generator is operated in a regeneration mode that charges a battery. The method includes where the idle speed is a first idle speed, and the first idle speed is less than a second idle speed, wherein the engine is operated at the second idle speed when the engine is coupled to the driveline. The method includes where the engine is operated at idle speed in response to the reduced driver request torque being less than a threshold torque of the driveline integrated starter / generator.

The methods and systems of 1 - 3 and 37 - 40 also provide a vehicle system comprising: an engine; a dual mass flywheel having a first side mechanically coupled to the engine; a driveline disconnect clutch having a first side mechanically coupled to a second side of the dual mass flywheel; a driveline integrated starter / generator (DISG) having a first side coupled to a second side of the driveline disconnect clutch; a transmission selectively coupled to the engine via the driveline disconnect clutch; and a controller having executable instructions stored in a non-volatile memory to provide a constant vehicle deceleration rate while the engine is operating at a neutral mode of sailing mode idling.

In one example, the vehicle system includes the sailing mode idle speed being a speed less than a base idle speed, the base idle speed being provided when the engine is coupled to the DISG. The vehicle system further includes additional commands to open the driveline disconnect clutch in response to decreasing driver demand torque. The vehicle system further includes additional commands to exit the sailing mode idle speed in response to increasing driver demand torque. The vehicle system further includes additional commands to increase engine speed from the sailing mode idle speed in response to increasing driver demand torque. The vehicle system includes providing the constant vehicle deceleration rate via the DISG.

The methods and systems of 1 - 3 and 37 - 40 also provide a driveline operating method, comprising: providing torque to a driveline via a driveline integrated starter / generator in response to a desired torque; and starting an engine and operating the engine at idle without providing engine torque to the driveline in response to the driver request torque being within a threshold range of engine cranking torque. In this way, different levels of desired driveline torque may be the basis for entering or leaving the sail mode. The method includes where the threshold range is greater than 75% of engine cranking torque. The method includes providing the DISG torque to a torque converter. The method includes where the engine is started via the driveline integrated starter / generator. The method includes where a driveline disconnect clutch is in an open state while the engine is idling. The method also includes where the desired torque is based on driver demand torque. The method includes that the engine starting torque is an amount of torque to accelerate the engine from a zero speed to a speed of less than 250 min ^-1.

The methods and systems of 1 - 3 and 37 - 40 also provide a driveline operating method, comprising: providing torque to a driveline via a driveline integrated starter / generator in response to a driver demand torque; Starting an engine and operating the engine at idle without providing engine torque to the driveline in response to the driver request torque being within a threshold range of engine cranking torque; and accelerating the engine to the speed of the driveline integrated starter / generator in response to the driver demand torque increasing to a threshold torque of the driveline integrated starter / generator. The method further includes closing a driveline disconnect clutch in response to the engine achieving the speed of the driveline integrated starter / generator.

In one example, the method further comprises providing engine torque to the driveline after closing the driveline disconnect clutch. The method includes where the engine is started via a starter other than the driveline integrated starter / generator. The method includes where the engine is started via the driveline integrated starter / generator. The method includes where the engine is idled at a sail mode idle speed. The method includes where a spark supplied to the engine while the engine is operating at the sailing mode idle speed is advanced more than when the engine is operated at a base idle speed.

The methods and systems of 1 - 3 and 37 - 40 also provide a vehicle system comprising: an engine; a dual mass flywheel having a first side mechanically coupled to the engine; a driveline disconnect clutch having a first side mechanically coupled to a second side of the dual mass flywheel; a driveline integrated starter / generator (DISG) having a first side coupled to a second side of the driveline disconnect clutch; a transmission selectively coupled to the engine via the driveline disconnect clutch; and a controller having executable instructions stored in a nonvolatile memory to accelerate the vehicle from a zero speed via the DISG without starting the engine and commands to start the engine in response to a desired torque Exceeds threshold engine starting torque.

In one example, the vehicle system further includes additional instructions for idling the engine at a sail idle speed without providing engine torque to the driveline. The vehicle system further includes additional commands to accelerate the engine from the sail idling speed in response to an increasing desired torque. The vehicle system further includes additional commands to close the driveline disconnect clutch in response to engine speed reaching the DISG speed. The vehicle system further includes additional commands for increasing engine torque after closing the driveline disconnect clutch. The vehicle system includes that the engine starting torque is an amount of torque to accelerate the engine from zero speed to an engine speed of less than 250 min ^-1.

The methods and systems of 1 - 3 and 37 - 40 also provide a powertrain operating method comprising: providing positive torque to a driveline via a driveline integrated starter / generator; Operating an engine at an idle speed in a speed control mode; and accelerating the engine in speed control mode to the speed of the driveline integrated starter / generator in response to a desired torque. In this way, the torque converter torque can be controlled during a stepped accelerator pedal condition. The method includes where the desired torque is driver demand torque and the driveline disconnect clutch disposed in the driveline between the engine and the driveline integrated starter / generator is in an open state.

In one example, the method further includes closing the driveline disconnect clutch in response to engine speed reaching or exceeding the speed of the driveline integrated starter / generator. The method includes where the idle speed is a sail mode idle speed. The method includes where the sail mode idle speed is a lower speed than a base engine idle speed. The method further includes advancing the engine spark timing while the engine is operating at the sailing mode idle speed with respect to the engine spark timing of the engine while the engine is operating at the base engine idle speed. The method further includes decreasing an engine air amount while the engine is operating at the sailing mode idle speed with respect to the engine air amount while the engine is operating at the base engine idle speed.

The methods and systems of 1 - 3 and 37 - 40 also provide a powertrain operating method comprising: providing positive torque to a driveline via a driveline integrated starter / generator; Operating an engine at an idle speed in a speed control mode; Adjusting the torque converter clutch slip and accelerating the engine in the speed control mode to the speed of the driveline integrated starter / generator in response to a desired torque; and closing a driveline disconnect clutch in response to the engine speed substantially equal to the speed of the driveline integrated starter / generator. The method includes where adjusting torque converter slip includes increasing torque converter slip. The method further includes reducing the torque converter slip in response to the driveline disconnect clutch being in a closed state.

In some examples, the method includes where the idle speed is a sail mode idle speed. The method includes where the sail mode idle speed is a lower speed than a base engine idle speed. The method includes increasing the desired torque. The method includes where the desired torque increases to a torque that is greater than a threshold torque of the driveline integrated starter / generator.

The methods and systems of 1 - 3 and 37 - 40 also provide a vehicle system comprising: an engine; a dual mass flywheel having a first side mechanically coupled to the engine; a driveline disconnect clutch having a first side mechanically coupled to a second side of the dual mass flywheel; a driveline integrated starter / generator (DISG) having a first side coupled to a second side of the driveline disconnect clutch; a transmission selectively coupled to the engine via the driveline disconnect clutch; and a controller having executable instructions stored in a nonvolatile memory to provide only positive torque to the transmission via the DISG in response to a desired torque being less than an engine cranking torque, and commands that adjust engine speed in that it follows the DISG speed when the DISG torque is greater than the engine cranking torque and less than a DISG threshold torque.

In one example, the vehicle system further includes additional instructions for closing the driveline disconnect clutch when the Engine speed is substantially equal to the DISG speed. The vehicle system further includes additional instructions for operating the engine in a torque control mode after closing the driveline disconnect clutch. The vehicle system further includes additional instructions for operating the engine in a speed control mode while adjusting the engine speed to track the DISG speed. The vehicle system further includes additional commands to provide the desired torque via the engine and the DISG. The vehicle system further includes a torque converter and a torque converter clutch, and further includes additional commands to increase the torque converter clutch slip in response to the desired torque.

The methods and systems of 1 - 3 and 37 - 40 also provide a powertrain operating method comprising: providing torque to a powertrain coupled to the vehicle wheels via an engine and a driveline integrated starter / generator (DISG); and entering a sailing mode during selected conditions, the sailing mode comprising delivering DISG torque to the driveline and idling the engine without providing engine torque to the driveline. The method includes where the selected conditions include a catalyst temperature that is less than a threshold temperature. The method includes where the selected conditions include a fuel vapor canister storing more than a threshold amount of fuel vapor. The method includes where the selected conditions include a vacuum level less than a threshold vacuum. The method includes where the selected conditions include an engine coolant temperature being less than a threshold temperature. The method includes where the selected conditions include a driver selecting a sport driving mode. The method includes where the engine is idling at a sail mode idle speed that is a lower idle speed than a base idle speed when the engine is coupled to the DISG.

The methods and systems of 1 - 3 and 37 - 40 also provide a powertrain operating method, comprising: providing torque to a powertrain coupled to vehicle wheels via an engine and a driveline integrated starter / generator (DISG); Entering a sailing mode during selected conditions, wherein the sailing mode comprises delivering a DISG torque to the driveline and operating the engine at idle without providing engine torque to the driveline; and advancing the spark timing and decreasing the engine air amount in response to entering the sailing mode. The method includes where the selected conditions include where a catalyst temperature is less than a threshold temperature and an energy storage device state of charge is equal to or greater than a threshold state of charge.

In some examples, the method includes where the selected conditions include a fuel vapor canister storing more than a threshold amount of fuel vapor and the energy storage device charge state being equal to or greater than a threshold charge state. The method includes where the selected conditions include a vacuum level less than a threshold vacuum and an energy storage device charge state equal to or greater than a threshold charge state. The method includes where the selected conditions include an engine coolant temperature less than a threshold temperature and an energy storage device charge state equal to or greater than a threshold charge state. The method includes where the selected conditions include where a driver has selected a sports drive mode and that an energy storage device charge state is equal to or greater than a threshold charge state. The method includes where the engine is idling at a sailing mode idle speed that is a lower idle speed than a base idle speed when the engine is coupled to the DISG.

The methods and systems of 1 - 3 and 37 - 40 also provide a vehicle system comprising: an engine; a dual mass flywheel having a first side mechanically coupled to the engine; a driveline disconnect clutch having a first side mechanically coupled to a second side of the dual mass flywheel; a driveline integrated starter / generator (DISG) having a first side coupled to a second side of the driveline disconnect clutch; a transmission selectively coupled to the engine via the driveline disconnect clutch; and a controller having executable instructions stored in a nonvolatile memory to enter a sailing mode during selected conditions, wherein the engine is operated at a sailing mode idle speed without providing engine torque to the transmission, and wherein the DISG torque is delivered to the transmission will, taking the selected conditions include that the battery state of charge is equal to or greater than a threshold battery charge.

In one example, the vehicle system further includes additional instructions for purging fuel vapors during sailing mode. The vehicle system further includes additional instructions for generating a negative pressure during the sailing mode. The vehicle system further includes additional commands to increase the catalyst temperature during the sailing mode. The vehicle system further includes additional commands to increase the engine temperature during the sailing mode. The vehicle system includes the threshold battery charge being a nominal battery charge.

Regarding 41 and 42 A flowchart of a method for adjusting a driveline disconnect clutch transfer function is shown. The procedure of 41 and 42 can as executable instructions in the non-volatile memory of the control unit 12 in 1 - 3 be saved.

at 4102 assess the procedure 4100 whether conditions for a driveline disconnect clutch adaptation exist or not. The driveline disconnect clutch adaptation may be implemented in an open state beginning with the driveline disconnect clutch and after the driveline disconnect clutch reaches a predetermined operating temperature and after the engine and the DISG reach selected operating conditions, such as at the end of the driveline disconnect clutch. Minimum engine and DISG operating temperatures. In yet another example, the driveline disconnect clutch adaptation may be provided in conditions where the torque converter impeller speed is greater than the torque converter turbine speed. If the procedure 4100 judged that there are conditions for a driveline disconnect clutch adaptation, the answer is Yes and the method 4100 go to 4104 further. Otherwise, the answer is no and the procedure 4100 continue to the end.

at 4104 opens the procedure 4100 the torque converter clutch (TCC) and the DISG are rotated when no torque sensor is present or when the engine is not rotating and burning. If a torque sensor is present, the torque measurement is not based on impeller speed. When the engine rotates and burns, the procedure requires 42 not that the DISG is spinning. When a DISG rotation is required, the DISG will rotate under its own power over current supplied by an energy storage device. In one example, the DISC with less than 1000 min ^-1 is rotated, so that very little torque is transmitted through the torque converter to the transmission. Thus, the DISG may be rotated at a speed that provides less than a threshold amount of torque through the torque converter to the transmission. The procedure 4100 go to 4106 continue after the TCC is open.

at 4106 assess the procedure 4100 Whether the engine turns and burns an air / fuel mixture or not. In one example, it may be judged that the engine is rotating and combusting an air / fuel mixture when the engine speed is greater than a threshold speed. If the procedure 4100 judging that the engine is rotating and burning an air / fuel mixture, the answer is Yes and the method 4100 go to 4150 further. Otherwise, the answer is no and the procedure 4100 go to 4108 further.

at 4150 operates the procedure 4100 the engine in a speed control mode. Further, the vehicle speed may be zero. The engine may combust an air / fuel mixture when the driveline disconnect clutch adjustment begins, or the engine may be started via a starter or the DISG. The converter clutch is in an open state and the engine speed is controlled via changing engine torque through the engine throttle, spark timing, cam timing, valve lift, fuel injection, or other actuators. The procedure 4100 go to 4152 after the engine is set in a speed control mode.

at 4152 puts the procedure 4100 set the engine speed above or below the DISG speed. For example, if the DISC speed is 400 min ^-1, the engine speed can be set to 800 min ^-1. Alternatively, the engine speed can be set for example to 700 min ^-1, if the DISC speed is 800 min ^-1. The procedure 4100 go to 4154 after the engine speed is set.

at 4154 appreciates the process 4100 the engine torque and stores the estimated engine torque in the memory. The engine torque can be estimated as in U.S. Patent No. 7,066,121 is described. Alternatively, the engine torque may be estimated via other known methods. For example, engine torque may be empirically determined at selected engine speeds and engine loads. The empirical data is stored in the controller memory and indexed by tables or functions on the base of the current engine speed and load. The procedure 4100 go to 4156 after the engine torque is estimated.

at 4156 increases the procedure 4100 incrementally the driveline disconnect clutch application pressure. In one example, the driveline disconnect clutch application pressure may be increased via increasing a duty cycle of a driveline disconnect clutch control signal. A higher duty cycle increases the oil pressure supplied to the driveline disconnect clutch. The incremental increase in driveline disconnect application pressure may be predetermined and stored in memory as the driveline disconnect clutch transfer function. The driveline disconnect clutch transfer function relates the driveline disconnect clutch application pressure and the driveline disconnect clutch input torque and outputs a driveline disconnect clutch output torque. The driveline disconnect clutch transfer function may also be used to select a driveline disconnect clutch application pressure by indexing the transfer function via a desired clutch output torque and clutch input torque.

The driveline disconnect clutch application pressure or the driveline disconnect clutch application force, engine speed, and DISG speed are stored in memory each time the driveline disconnect clutch application pressure is increased. Each time the disconnect torque is changed to a new level (there may be multiple levels used in turn to learn the clutch transfer function, as by the method 4130 and 43 ), the system must wait until the engine speed stabilizes at the desired engine speed, and then stores a new estimate of engine torque. Once the engine speed control unit has suppressed any disturbance from the change in clutch torque, both the estimated engine torque and the estimated clutch torque for use become available 4160 saved. The engine controller may use the estimated disconnect clutch pressure or clutch capacity and sign of slip across the disconnect clutch to proactively increase or decrease engine torque if desired, or the engine controller may use only the feedback control to compensate for engine speed for changes in disconnect clutch pressure. The procedure 4100 go to 4158 after the driveline disconnect clutch application pressure is increased.

at 4158 assess the procedure 4100 Whether the driveline disconnect clutch application profile has been fully applied or not. In one example, the driveline disconnect clutch application profile provides only enough pressure to transmit a minimum torque (eg, 2 Nm) for one clutch plate to just begin to contact the other clutch plate. In other examples, the driveline disconnect application profile may transition from fully open to fully closed. If the procedure 4100 judges that not all application pressures of the driveline disconnect clutch profile have been applied, the answer is no and the method 4100 returns 4154 back. Otherwise, the answer is yes and the procedure 4100 go to 4160 further.

at 4160 compares the procedure 4100 the driveline disconnect clutch torque estimate (s) from the driveline disconnect clutch transfer function with the engine torque estimate (s) stored when the engine speed at the desired speed was stabilized at each of the commanded disconnect clutch pressures when the driveline disconnect clutch transfer function via incrementing the driveline disconnect clutch Application pressure is applied. For example, when the driveline disconnect clutch transfer function outputs a driveline disconnect clutch duty cycle of 35% (corresponding to a desired driveline disconnect clutch application pressure or desired driveline disconnect clutch application force) to achieve a desired disconnect clutch output torque of 50Nm when the driveline disconnect clutch input torque is 85Nm, but that The driveline disconnect clutch output torque is 45 Nm, as estimated by the engine torque estimator, it can be judged that the driveline disconnect clutch transfer function has an error of 5 Nm when the 35% duty cycle is applied to the driveline disconnect clutch when the driveline disconnect clutch input torque is 85 Nm is. The difference between the desired driveline disconnect clutch torque and the engine torque may be determined for each set of operating conditions when the driveline disconnect clutch transfer function occurs 4156 was applied. The procedure 4100 go to 4162 after the driveline disconnect clutch torque, as defined by the driveline disconnect clutch transfer function, with the torque estimated by the engine is compared when the driveline disconnect clutch application pressure is incremented.

at 4162 updates the procedure 4100 the driveline disconnect clutch transfer function at selected inputs in response to an error between the driveline disconnect clutch torque estimated by the engine and the driveline disconnect clutch torque expected based on the driveline disconnect clutch transfer function. When the driveline disconnect clutch torque estimated by the engine is different from the driveline disconnect clutch torque estimated by the driveline disconnect clutch transfer function, the driveline disconnect clutch torque estimated by the engine replaces, in one example, the corresponding driveline disconnect clutch torque value in the driveline disconnect clutch transfer function. In this way, the engine torque estimator may be the basis for adjusting the driveline disconnect clutch transfer function. The procedure 4100 go to 4164 after the disconnect transfer function is updated at selected values, the driveline disconnect clutch torque estimated by the engine does not match the driveline disconnect clutch torque described in the driveline disconnect clutch transfer function.

If the difference between the engine torque based on the estimated clutch torque and the previous clutch torque is above a threshold, the adjustment sequence may be performed again to test the system again at the next opportunity and the adjustment sequence may be executed until the system succeeds is adjusted. It should be noted that all of the adjustment methods described herein may be performed more frequently, earlier or immediately in response to an amplitude of the driveline disconnect clutch transfer function error.

at 4164 applies the procedure 4100 Check the driveline disconnect clutch transfer function for the planned driveline disconnect clutch pressure. For example, when a setting on the driveline disconnect clutch pressure is requested, the driveline disconnect clutch pressure is established based on the tested driveline disconnect clutch transfer function 4162 output. The procedure 4100 ends after the tested driveline disconnect clutch pressures are output.

at 4108 assess the procedure 4100 Whether an engine restart is required or not. When the engine rotation at 4108 stopped, it can be restarted if desired. When engine restart is requested during driveline disconnect clutch adaptation, it may be possible for there to be faults in the adjusted driveline disconnect clutch transfer function. Therefore, the driveline disconnect clutch adjustment is not performed during engine restart. If the procedure 4100 determines that engine restart is desired, the answer is Yes and the method 4100 continue to the end. Otherwise, the answer is no and the procedure 4100 go to 4110 further.

at 4110 assess the procedure 4100 whether or not there is a driveline torque sensor to detect the driveline torque. If the procedure 4100 judges that there is a driveline torque sensor, the answer is Yes and the method 4100 go to 4130 further. Otherwise, the answer is no and the procedure 4100 go to 4112 further.

It should be noted that, in some examples, the driveline disconnect clutch adaptation based on the torque converter (e.g. 4112 - 4122 ) or the torque sensor (eg 4130 - 4138 ) simultaneously with the estimation of the driveline disconnect clutch torque based on the engine torque (e.g. 4150 - 4164 ) may be performed when the engine and DISG speeds are kept separate (eg, the driveline disconnect clutch is being drifted) and the engine control unit is operating in closed loop engine speed control.

at 4130 increases the procedure 4100 the driveline disconnect clutch pressure from a state in which the driveline disconnect clutch is in a fully open state by sequentially increasing driveline disconnect clutch application pressure. The driveline disconnect clutch pressure may be increased at a predetermined rate or in accordance with a predetermined group of selected driveline disconnect clutch application pressure increments. The procedure 4100 increases after increasing the driveline disconnect clutch application pressure 4132 further. The DISC can in the speed feedback mode with a constant commanded engine speed (z. B. idle speed ~ 700 min ^-1) are operated. Alternatively, the DISG speed may be selected as the lower speed to reduce power consumption.

at 4132 puts the procedure 4100 the DISG torque based on the present driveline disconnect clutch transfer function, which is subjected to an adjustment after the driveline disconnect clutch application procedure is completed. Specifically, the DISG torque is increased according to the driveline disconnect clutch transfer function based on the estimated amount of torque to be transmitted from the DISG to the engine via the driveline disconnect clutch. The procedure 4100 go to 4134 continue after the DISG torque is set.

at 4134 compares the procedure 4100 the amount of torque transmitted by the driveline disconnect clutch with the commanded driveline disconnect clutch transfer torque (eg, the amount of driveline disconnect clutch torque requested via the driveline disconnect clutch transfer function). In one example, the driveline disconnect clutch torque may be determined via the following equations depending on the location of the powertrain torque sensor:
When the torque sensor is located on the torque converter impeller: T ^ _clutch = I _{elec_machine} · N. _impeller + T _sensor - T _{elec_machine}

When the torque sensor is at the torque converter turbine / torque converter input shaft: T ^ _clutch = I _{elec_machine} · N. _impeller + T _sensor - T _{elec_machine} - T _turbine

In which

Where T ^ _{clutch is} the estimated _{driveline disconnect clutch} torque, I _{elec_machine is} the inertia of the DISG, N _{impeller is} the torque converter impeller _speed , T _{sensor is} the torque measured via the torque _sensor , T _{elec_machine is} the output torque of the DISG, T _{turbine is} the torque of the torque converter Turbine wheel is, cpc is the torque converter capacity factor, N _{turbine is} the torque converter turbine _speed , and T _{conv_clutch is} the torque converter _clutch torque.

In conditions in which the torque converter turbine speed is less than the torque converter pump wheel, the torque converter clutch is open, the drive train clutch is open (for. Example, is a desirable case, the vehicle is at rest, wherein the impeller rotates ~ 700 min ^-1 ), adaptively correcting the capacity factor (cpc) of the torque converter based on the engine torque and the impeller acceleration using the above equations. In conditions where the torque converter impeller is rotating, the driveline disconnect clutch is open and engine restart is not commanded, the driveline disconnect clutch torque is sequentially commanded higher. Based on the current estimate of the driveline disconnect clutch lift pressure or point of contact (eg, the driveline disconnect clutch is commanded to a point where the driveline disconnect clutch plates on the input and output sides of the driveline disconnect clutch first contact each other when the driveline disconnect clutch is in an open condition in a partially closed state) of the driveline disconnect clutch, the driveline disconnect clutch torque is compensated via the DISG torque to reduce vehicle drivability impact. In one example, the DISG torque is increased in proportion to an amount of the estimated driveline disconnect clutch torque based on the current clutch transfer function.

The driveline disconnect clutch torque estimate may be compared to the measurement from the torque sensor with appropriate compensation of torques and inertias between the driveline disconnect clutch and the torque sensor. The driveline disconnect clutch lift pressure / touch point can be adaptively adjusted. In one example, the driveline disconnect clutch transfer function is set via the replacement of a value in the driveline disconnect clutch transfer function with the estimated driveline disconnect clutch torque. Alternatively, the driveline disconnect clutch transfer function may be adjusted based on an error between the driveline disconnect clutch transfer function and the estimated driveline disconnect clutch torque.

When the commanded driveline disconnect clutch torque is less than or greater than the amount of torque transmitted by the driveline disconnect clutch, the driveline disconnect clutch torque value in the driveline disconnect clutch transfer function is adjusted to the measured driveline disconnect clutch torque at the operating point.

In this manner, the driveline disconnect clutch transfer function may be adjusted to provide an improved estimate of the amount of torque transmitted by the driveline disconnect clutch. The procedure 4100 go to 4136 after the driveline disconnect clutch transfer function has been evaluated and / or adapted to the current operating conditions.

at 4136 assess the procedure 4100 whether or not all desired portions of the driveline disconnect clutch transfer function have been evaluated and / or adjusted at all desired driveline disconnect clutch application pressures. If so, the answer is yes and the procedure 4100 go to 4138 further. Otherwise, the answer is no and the procedure 4100 returns 4130 where the driveline disconnect clutch apply pressure is increased and the driveline disconnect clutch torque transfer function is evaluated at a new operating condition.

at 4138 applies the procedure 4100 Check the driveline disconnect clutch transfer function for the planned driveline disconnect clutch pressure. For example, when a setting on the driveline disconnect clutch pressure is requested, the driveline disconnect clutch pressure is established based on the tested driveline disconnect clutch transfer function 4134 output. The procedure 4100 ends after the tested driveline disconnect clutch pressures are output.

at 4112 increases the procedure 4100 the driveline disconnect clutch application pressure from a state in which the driveline disconnect clutch is fully open as in 4130 described. The vehicle speed may be zero at this time and the driveline disconnect clutch command may be incrementally increased to increase the driveline disconnect clutch application pressure or the driveline disconnect clutch application force. The procedure 4100 go to 4114 after the driveline disconnect clutch application pressure is adjusted.

at 4114 puts the procedure 4100 the DISG torque, as at 4132 described. The procedure 4100 go to 4116 continue after the DISG torque is set.

at 4116 appreciates the process 4100 the torque transmitted by the driveline disconnect clutch based on engine speed and acceleration driveline component speeds. In one example, the torque transmitted by the driveline disconnect clutch may be estimated using the following equations: I _impeller · N. _impeller = T _clutch + T _{elec_mach} - T _conv

In which:

Resolve after the driveline disconnect clutch torque: T ^ _clutch = I _impeller · N. _impeller - T _{elec_mach} + T _conv

Where I _{impeller is} the torque converter impeller _inertia , N _{impeller is} the torque converter impeller _speed , T _{clutch is} the _{driveline disconnect clutch} torque, T _{elec_machine is} the DISG torque, T _{conv is} the torque converter impeller torque, cpc is the torque converter capacity factor, N _turbine is the torque converter turbine _speed and T _{conv_clutch is} the torque converter _clutch torque.

In conditions where the torque converter turbine speed is less than the torque converter impeller speed, the torque converter lock-up clutch is open, the driveline disconnect clutch is open (eg, a desired case is a vehicle at rest with the impeller rotating ~ 700 min ^-1 ), the torque converter capacity factor (cpc) based on engine torque and impeller acceleration is adaptively corrected via the above equations. In conditions where the impeller is rotating, the driveline disconnect clutch is open and engine restart is not commanded, sequentially higher driveline disconnect clutch torques are commanded. The driveline disconnect clutch torque is compensated via the DISG torque to reduce driveability impact. The driveline disconnect clutch torque is based on the current estimate of the driveline disconnect clutch lift pressure or the driveline disconnect point of contact.

For example, the DISG torque is increased as the driveline disconnect clutch torque is increased. In one example, the DISG torque is increased in proportion to the torque transmitted via the driveline disconnect clutch. The driveline disconnect clutch torque estimate is provided with a driveline disconnect clutch torque calculated using the above equations based on other torques, speeds, and accelerations 4118 compared. Then, the driveline disconnect clutch lift pressure / Touch point of the driveline disconnect clutch adaptive at 4118 updated. The procedure 4100 go to 4118 after the amount of torque transmitted from the driveline disconnect clutch is estimated.

at 4118 compares the procedure 4100 the estimated torque transmitted from the driveline disconnect clutch with the driveline disconnect clutch torque from the current driveline disconnect clutch transfer function as at 4134 described. The comparison may be performed by subtracting the estimated driveline disconnect clutch torque from the desired driveline disconnect clutch torque to provide a fault that is the basis for adjusting the driveline disconnect clutch transfer function. If the error is greater than a predetermined amount, the estimated driveline disconnect clutch torque replaces the value of the driveline disconnect clutch in the driveline disconnect clutch transfer function or is the basis for adjusting the driveline disconnect clutch transfer function. The procedure 4100 go to 4120 After the estimated amount of torque transmitted from the driveline disconnect clutch is compared to the driveline disconnect clutch torque from the driveline disconnect clutch transfer function.

at 4120 assess the procedure 4100 whether or not all desired sections of the driveline disconnect clutch transfer function have been evaluated and / or adjusted at all desired driveline disconnect clutch application pressures. If so, the answer is yes and the procedure 4100 go to 4122 further. Otherwise, the answer is no and the procedure 4100 returns 4112 where the driveline disconnect clutch apply pressure is increased and the driveline disconnect clutch torque transfer function is evaluated at a new operating condition.

at 4122 applies the procedure 4100 Check the driveline disconnect clutch transfer function for the planned driveline disconnect clutch pressure. For example, when a setting on the driveline disconnect clutch pressure is requested, the driveline disconnect clutch pressure is established based on the tested driveline disconnect clutch transfer function 4118 output. The procedure 4100 ends after the tested driveline disconnect clutch pressures are output.

In some examples, the driveline disconnect clutch may be used in combination with a dual clutch automatic transmission (DCT) (e.g. 3 ) be used. In these applications, the DISG may be used as a torque sensing device for measuring DCT launch clutch torque as a function of commanded DCT launch clutch torque at the low torque levels at which the launch clutch operates during engine restart and start-up. The gain and / or offset may then be updated in the DCT launch clutch torque tables to match the actual input to the output torque. An example of using the DISG to detect the DCT launch clutch torque includes: measuring DCT launch clutch torque when the vehicle is stopped and the brakes are applied, e.g. B. when the vehicle is at rest and the driver applies the brake or the brake system is ordered to delay the brake release. Such operation may be used to prevent the change in DCT clutch torque from either being transmitted to the wheels or affecting vehicle acceleration.

In some examples, the driveline disconnect clutch may be open. An open driveline disconnect clutch removes engine or dual mass flywheel (DMF) torque or compliance interactions that may affect the ability of the DISG to accurately detect the DCT launch clutch torque. The DISG may operate in the speed feedback mode at a constant commanded speed, e.g. B. idle speed ~ 700 min ^-1 , operated. The DISG speed can be selected as a lower speed to reduce energy consumption. The DISG speed may be set so as to maintain the hydraulic pressure in the automatic transmission (AT) using the DISG to rotate the transmission hydraulic pump. Operating the DISG to maintain the transmission oil pressure is for a DCT with hydraulic clutches versus a dry clutch DCT.

In some examples, the DCT starting clutch is fully open (eg, with zero torque capacity) when learning a DISG torque estimate. The DISG torque estimate is the basis for recording the starting clutch torque of the open DCT at the commanded DISG speed. The DISG torque estimate is a function of the DISG three-phase currents or a commanded torque from an inner loop of the DISG speed feedback control. The DCT startup clutch is commanded to operate over a desired range of torque after the torque of the open DCT startup clutch has been determined from the DISG torque estimate. The DCT startup clutch torques for each commanded torque in the desired torque range are eliminated determines the DISG torque determined at each commanded torque. A DCT startup clutch error torque is determined as the difference between the torque measurement of the open DCT starting clutch and the detected torque from the torque estimate of the DISG three-phase current or the commanded torque. The DISG may be operated in the speed feedback mode, which includes an inner torque loop when the DCT launch clutch torque is determined. The DCT torque table or transfer function is updated according to the observed DISG torque.

Further, the variability in the operation and estimation of the torque transmitted via a TCC may be a noise factor that may contribute to poor drivability of the vehicle system. If the TCC torque is not properly actuated due to errors in commanded versus actual TCC torque during the engine restart process, the torque transmitted to the wheels may be less than desired and the launch performance and driveability may be degraded.

The DISG may be operated as a torque sensing device to measure torque transmitted through the TCC as a function of commanded TCC torque during engine startup. The low torque levels transmitted via the TCC during engine startup and startup may be the basis for updating gain and / or offset values in TCC torque tables such that the table values match the actual input torque to the output torque.

An example of operating the DISG to detect the transmitted TCC torque includes: measuring TCC torque via the DISG when the vehicle is stopped and when the brakes are applied (eg, when the vehicle is at rest) and the driver applies the brake). Another example involves estimating the transmitted TCC torque via the DISG when automatic transmission clutches moor the transmission output for roll back protection purposes. The mooring of the transmission reduces the possibility that a transmitted TCC torque will be transmitted to the vehicle wheels.

The torque transmitted through the TCC can be more accurately determined when the driveline disconnect clutch is open because it removes engine, dual mass flywheel, or compliance interactions that may affect the DISG torque estimates. The DISC can be in the speed feedback mode at a low constant commanded speed (z. B. idle speed ~ 700 min ^-1) can be operated to reduce the power consumption when the DISC is the basis of the TCC torque transmission estimates. The DISG speed can also be adjusted to maintain the hydraulic pressure in the torque converter by turning the transmission over the DISG.

The TCC transfer function, which describes the amount of torque transmitted by the TCC at selected application pressures or forces, may be adjusted based on DISG torque estimates. In one example, the TCC is commanded to be fully open (eg, with zero torque capacity) and the torque converter output is estimated based on the DISG current. The DISG current is converted to a torque that is subtracted from torques determined on other TCC commands, with the TCC not commanded to be fully open. Consequently, a torque offset is determined and stored in memory when the TCC is commanded to be fully open. The TCC is then commanded in increments over a desired torque range, while the DISG torque is estimated from the DISG current at each commanded torque. A TCC transfer torque error amount is determined from a difference between the open loop TCC torque command (eg, TCC transfer function) and the TCC torque as determined from the DISG three phase current. The TCC transfer function may be updated based on the TCC transfer torque error. In one example, a fraction of each TCC transfer torque error is added to the current value in the TCC transfer function corresponding to the TCC transfer torque error.

In this way, the driveline disconnect clutch transfer function can be checked so that the driveline disconnect clutch can be more accurately applied. Further, the driveline disconnect clutch transfer function may be checked without taking actions that may be noticeable to the driver.

Regarding 43 FIG. 12 is an example sequence for updating or adjusting a driveline disconnect transfer function according to the methods of FIG 41 and 42 shown. The sequence of 43 can through the system of 1 - 3 to be provided.

The first diagram from the top of 43 represents the torque converter impeller speed as a function of time. The Y axis represents the torque converter impeller speed and the torque converter impeller speed increases in the direction of the Y axis arrow. The X-axis represents the time and the time increases from the left side of the figure to the right side of the figure. The horizontal line 4302 represents a desired torque converter impeller speed.

The second diagram from the top of 43 represents the DISG torque as a function of time. The Y axis represents the DISG torque and the DISG torque increases in the direction of the Y axis arrow. The X-axis represents the time and the time increases from the left side of the figure to the right side of the figure.

The third diagram from the top of 43 represents the driveline disconnect clutch application force or the driveline disconnect clutch application pressure as a function of time. The y-axis represents the driveline disconnect clutch application force or the driveline disconnect clutch application pressure and the application force or application pressure increases in the direction of the y-axis arrow. The X-axis represents the time and the time increases from the left side of the figure to the right side of the figure.

Prior to time _T102 , the torque converter impeller speed is at the desired torque converter impeller speed 4302 and the DISG torque is at a lower level. The driveline disconnect clutch pressure is also at a lower level. When the DISG is in speed control, the amplitude of the change in DISG torque required to maintain the desired impeller speed can be used as a torque estimation mechanism similar to the manner in which engine torque is measured in FIG 42 is used.

At time T ₁₀₂ , the driveline disconnect clutch pressure is increased in response to a request to increase the torque transmitted by the driveline disconnect clutch. The DISG torque is not increased because the driveline disconnect clutch transfer function indicates that the torque at the current commanded value is not being transmitted by the driveline disconnect clutch. The torque converter impeller speed remains at the desired torque converter impeller speed during the closed loop speed control mode, or the DISG torque need not change, and indicates that the driveline disconnect clutch torque transfer function that estimates the driveline disconnect clutch torque is correct. The driveline disconnect pressure is reduced after being increased so that the next increase in disconnect clutch pressure may be initiated from a known condition.

At time T ₁₀₃ , the driveline disconnect clutch pressure is increased a second time in response to a request to increase the torque transmitted by the driveline disconnect clutch. Again, the DISG torque is not increased because the driveline disconnect clutch transfer function indicates that the torque at the current commanded value is not being transmitted by the driveline disconnect clutch. The torque converter impeller speed decreases due to the closed loop speed control or the DISG torque increases to indicate that the driveline disconnect clutch torque transfer function underestimates the driveline disconnect clutch torque that is being transmitted. The driveline disconnect clutch transfer function fault may be determined by a torque sensor on the disconnect clutch, DISG power, or a model as in FIG 4116 described. The driveline disconnect clutch transfer function is set based on the error. In particular, in this example, the torque estimated for the output command is reduced by a predetermined amount. Alternatively, the output command for the driveline disconnect clutch may be reduced by a predetermined amount. The driveline disconnect pressure is reduced after being increased so that the next increase in disconnect clutch pressure may be initiated from a known condition.

At time T ₁₀₄ , the driveline disconnect clutch pressure is increased a third time in response to a request to increase the torque transmitted by the driveline disconnect clutch. The DISG torque is increased because the driveline disconnect clutch transfer function indicates that the torque is transmitted by the driveline disconnect clutch at the current commanded value. The torque converter impeller speed increases or the DISG torque is adjusted via the closed loop speed control so as not to increase as much as the disconnect clutch transfer function would indicate to indicate that the driveline disconnect clutch torque transfer function is the driveline disconnect clutch torque being transmitted. overestimated. The driveline disconnect clutch transfer function fault may be determined and the driveline disconnect clutch transfer function set based on the error. In particular, in this example, the torque estimated for the output command is increased by a predetermined amount. Alternatively, the output command for the driveline disconnect clutch may be increased by a predetermined amount. The driveline disconnect pressure is reduced after being increased so that the next increase in disconnect clutch pressure may be initiated from a known condition.

At time T ₁₀₅ , the driveline disconnect clutch pressure is increased a fourth time in response to a request to increase the torque transmitted by the driveline disconnect clutch. The DISG torque is increased because the driveline disconnect clutch transfer function indicates that the torque is transmitted by the driveline disconnect clutch at the current commanded value. The torque converter impeller speed remains constant to indicate that the driveline disconnect clutch torque transfer function correctly estimates the driveline disconnect clutch torque that is being transmitted. The driveline disconnect clutch transfer function is not adjusted because there is less than a threshold amount of error in the driveline disconnect clutch torque transfer estimate. The driveline disconnect pressure is reduced after being increased so that the next increase in disconnect clutch pressure may be initiated from a known condition.

In this way, a transfer function describing the torque transmitted by a driveline disconnect clutch may be adjusted. Each driveline disconnect clutch application pressure in the transfer function may be adjusted in this manner so that the entire transfer function can be checked as the vehicle ages.

Regarding 44 FIG. 12 is an example sequence for updating or adapting a driveline disconnect clutch transfer function according to the method of FIG 42 shown. The sequence of clutch torques, which in 43 can be shown on the sequence of 42 be applied. The sequence of 44 can through the system of 1 - 3 to be provided.

The first diagram from the top of 44 represents the engine speed as a function of time. The Y-axis represents the engine speed and the engine speed increases in the direction of the Y-axis arrow. The X-axis represents the time and the time increases from the left side of the figure to the right side of the figure. The horizontal line 4402 represents a desired engine speed.

The second diagram from the top of 44 represents the engine torque as a function of time. The Y-axis represents the engine torque and the engine torque increases in the direction of the Y-axis arrow. The X-axis represents the time and the time increases from the left side of the figure to the right side of the figure.

The third diagram from the top of 44 represents the driveline disconnect clutch application force or the driveline disconnect clutch application pressure as a function of time. The y-axis represents the driveline disconnect clutch application force or the driveline disconnect clutch application pressure and the application force or application pressure increases in the direction of the y-axis arrow. The X-axis represents the time and the time increases from the left side of the figure to the right side of the figure.

Before time T ₁₀₆ , engine speed is at the desired engine speed 4402 and the engine torque is at a lower level. The driveline disconnect clutch pressure is also at a lower level, commanding the driveline disconnect clutch to an open position. The engine is in a speed control mode and the engine torque is determined by engine speed and load (eg, current engine air mass divided by the theoretical air mass that the engine may prime, whether without charge or with boost). The DISG and torque converter speed (not shown) are set at a speed other than the desired engine speed.

At time T ₁₀₆ , the driveline disconnect clutch pressure is increased in response to a request to increase the torque transmitted by the driveline disconnect clutch. The DISG speed (not shown) remains constant and the desired engine speed remains constant as the driveline disconnect clutch application force is increased. The engine torque initially remains at a constant level as the driveline disconnect clutch is gradually closed.

At time T ₁₀₇ , the driveline disconnect clutch pressure continues to increase and engine speed begins to slow to a speed that is less than the desired engine speed. The engine speed control loop increases engine torque (eg, via opening the engine throttle) in response to the difference between the desired engine speed and the actual engine speed. The estimated driveline disconnect clutch torque is the difference between the Engine torque prior to time T ₁₀₆ and engine torque at time T ₁₀₆ when the driveline disconnect clutch application force is increased (eg, at a time shortly after time T ₁₀₇ ). The driveline disconnect clutch transfer function, which outputs a driveline disconnect clutch application force or a driveline disconnect clutch application pressure in response to a desired driveline disconnect clutch torque, may be adjusted based on the estimated driveline torque.

In this example, the driveline disconnect clutch transfer function entries that differ from the estimated driveline disconnect clutch torque values determined at the commanded driveline disconnect clutch pressures may be updated to the estimated driveline disconnect clutch torque or a fraction of the error if it is less than the estimated driveline disconnect clutch torque by more than a threshold amount of the estimated driveline disconnect clutch torque Torque deviate. The driveline disconnect clutch transfer function may be updated when the adjustment process takes place or after the sequence is completed. It should also be noted that engine speed may increase rather than decrease at time T ₁₀₇ when the torque converter impeller speed is greater than the engine speed. In this example, the torque converter impeller speed is set to a speed greater than the engine speed such that the engine speed increases at time T ₁₀₇ when the driveline disconnect clutch is closed.

At time T ₁₀₈ , the driveline disconnect clutch pressure is reduced in response to a request to reduce the torque transmitted by the driveline disconnect clutch. The actual engine speed is greater than the desired engine speed after the driveline disconnect clutch application pressure is reduced. The driveline disconnect clutch transfer function may be updated as the estimated driveline disconnect clutch torque deviates from the driveline disconnect clutch transfer function input from the estimated driveline disconnect clutch torque.

In this way, a transfer function describing the torque transmitted by a driveline disconnect clutch may be adjusted. Each driveline disconnect clutch application pressure in the transfer function may be adjusted in this manner so that the entire transfer function can be checked as the vehicle ages.

The methods and systems of 1 - 3 and 41 - 44 also provide a driveline disconnect clutch adjustment method comprising: adjusting the application force of a driveline disconnect clutch in a vehicle driveline in response to a torque sensor while an engine in the vehicle driveline is not combusting air and fuel. In this way, a driveline disconnect clutch transfer function may be adjusted to improve vehicle handling. The method further comprises adjusting the transfer function of the driveline disconnect clutch in response to the torque sensor. The method includes adjusting a transfer function of the driveline disconnect clutch in response to a response of driveline components.

In some examples, the method includes setting the application of the driveline disconnect clutch based on increasing driveline disconnect clutch application pressures from a condition in which the driveline disconnect clutch is open. The method includes where a driveline integrated starter / generator rotates while adjusting the application of the driveline disconnect clutch. The method includes where a transmission lock-up clutch is open during adjustment of the application of the driveline disconnect clutch.

The methods and systems of 1 - 3 and 41 - 44 also provide a driveline disconnect clutch adjustment method, comprising: rotating a torque converter impeller at a speed less than a speed at which more than a threshold percentage of torque at the torque converter impeller is transmitted to a torque converter turbine, wherein the torque converter Pump impeller is located in a vehicle driveline; and adjusting the application force of a driveline disconnect clutch in the vehicle driveline in response to a torque sensor while an engine in the vehicle driveline is not combusting air and fuel. The drive train break coupling adjustment method comprises that the speed is less than 700 min ^-1.

In one example, the driveline disconnect clutch adjustment method includes adjusting application force via adjusting a driveline disconnect clutch transfer function. The driveline disconnect clutch adjustment method further includes increasing a driveline disconnect clutch command and adjusting the driveline disconnect clutch transfer function based on an output of the torque sensor. The driveline disconnect clutch adjustment method further comprises Commanding the opening of a torque converter clutch. The driveline disconnect clutch adjustment method includes rotating the torque converter impeller via a driveline integrated starter / generator. The driveline disconnect clutch adjustment method includes where the driveline integrated starter / generator rotates at a speed that produces a threshold transmission oil pressure that maintains a transmission clutch in an applied condition. The driveline disconnect clutch adjustment method includes where the torque converter impeller rotates at a speed greater than a speed of the torque converter turbine wheel.

The methods and systems of 1 - 3 and 41 - 44 also provide a vehicle system comprising: an engine; a dual mass flywheel having a first side mechanically coupled to the engine; a driveline disconnect clutch having a first side mechanically coupled to a second side of the dual mass flywheel; a driveline integrated starter / generator (DISG) having a first side coupled to a second side of the driveline disconnect clutch; a transmission selectively coupled to the engine via the driveline disconnect clutch; and a controller having executable instructions stored in a nonvolatile memory for setting an estimate of the torque transmitted by the driveline disconnect clutch in response to a torque sensor output. The vehicle system includes the engine not burning air and fuel.

In some examples, the vehicle system further comprises rotating the DISG at a speed at which a threshold percentage of the DISG torque is transmitted to the transmission. The vehicle system further includes a torque converter having a torque converter clutch and additional instructions for opening the torque converter clutch while adjusting the estimate of the torque transmitted by the driveline disconnect clutch. The vehicle system further includes additional instructions for rotating an impeller of the torque converter at a higher speed than a turbine of the torque converter. The vehicle system further includes additional commands to increase a closing force applied to the driveline disconnect clutch.

The methods and systems of 1 - 3 and 41 - 44 also provide a driveline disconnect clutch adjustment method comprising: rotating a torque converter impeller at a first speed; Operating an engine in a speed control mode and rotating the engine at a second speed different than the first speed; and adjusting a driveline disconnect clutch transfer function in response to a torque estimate based on engine operating conditions. The method includes rotating the torque converter impeller via a driveline integrated starter / generator.

In some examples, the method includes where the second speed is greater than the first speed. The method includes where the second speed is less than the first speed. The method includes where engine operating conditions are engine speed and engine load. The method further includes commanding an increase in the application force of a driveline disconnect clutch. The method further includes adjusting engine torque to maintain engine speed at the second speed while commanding the increase in application force of the driveline disconnect clutch.

The methods and systems of 1 - 3 and 41 - 44 also provide a driveline disconnect clutch adjustment method comprising: rotating a torque converter impeller at a first speed; Operating an engine in a speed control mode and rotating the engine at a second speed different than the first speed; Storing an engine torque output value in response to an open driveline disconnect clutch; incrementally closing the driveline disconnect clutch; and adjusting a driveline disconnect clutch transfer function in response to a difference between a torque estimate based on the engine operating conditions and a torque estimate based on the driveline disconnect clutch transfer function.

In one example, the drive train break coupling adjustment method includes the first speed is less than 700 min ^-1. The driveline disconnect clutch adjustment method includes where engine operating conditions are engine speed and load. The driveline disconnect clutch adjustment method includes where the torque estimate based on the engine operating conditions is an engine torque minus an engine torque stored during the open driveline disconnect clutch. The driveline disconnect clutch adjustment method also includes adjusting engine speed via adjusting engine torque during the speed control mode becomes. The driveline disconnect clutch adjustment method includes rotating the torque converter impeller via a driveline integrated starter / generator. The driveline disconnect clutch adjustment method includes where the driveline integrated starter / generator rotates at a speed that produces a threshold transmission oil pressure that maintains a transmission clutch in an applied condition. The driveline disconnect clutch adjustment method includes where the torque converter impeller rotates at a speed greater than a speed of the torque converter turbine wheel.

The methods and systems of 1 - 3 and 41 - 44 also provide a vehicle system comprising: an engine; a dual mass flywheel having a first side mechanically coupled to the engine; a driveline disconnect clutch having a first side mechanically coupled to a second side of the dual mass flywheel; a driveline integrated starter / generator (DISG) having a first side coupled to a second side of the driveline disconnect clutch; a transmission selectively coupled to the engine via the driveline disconnect clutch; and a controller having executable instructions stored in nonvolatile memory to set an estimate of torque transmitted by the driveline disconnect clutch in response to an engine torque estimate. The vehicle system includes where the engine torque estimate is based on engine speed and load.

In some examples, the vehicle system further includes additional instructions for rotating the DISG and the engine at a speed at which a threshold percentage of the DISG torque is transmitted to the transmission. The vehicle system further includes additional instructions for rotating the DISG at a speed that is less than a speed of engine rotation. The vehicle system further includes additional instructions for performing closed loop engine speed control via adjusting engine torque while estimating engine torque.

The methods and systems of 1 - 3 and 41 - 44 also provide a driveline disconnect clutch adjustment method, comprising: adjusting an application force of a driveline disconnect clutch in a vehicle driveline in response to a torque sensor while an engine in the vehicle driveline is not combusting air and fuel. The method further comprises adjusting a transfer function of the driveline disconnect clutch in response to the torque sensor. The method includes adjusting a transfer function of the driveline disconnect clutch in response to a response of driveline components. The method includes setting the application of the driveline disconnect clutch based on increasing the driveline disconnect clutch application pressure from a condition in which the driveline disconnect clutch is open. The method includes where a driveline integrated starter / generator rotates while adjusting the application of the driveline disconnect clutch. The method includes where a transmission lock-up clutch is open during adjustment of the application of the driveline disconnect clutch.

The methods and systems of 1 - 3 and 41 - 44 also provide a driveline disconnect clutch adjustment method comprising: rotating a torque converter impeller at a speed less than a speed at which more than a threshold percentage of torque at the torque converter impeller is transmitted to a torque converter turbine, wherein the torque converter Pump impeller is located in a vehicle driveline; and adjusting the application force of a driveline disconnect clutch in the vehicle driveline in response to a torque sensor while an engine in the vehicle driveline is not combusting air and fuel. The drive train break coupling adjustment method comprises that the speed is less than 700 min ^-1.

In some examples, the driveline disconnect clutch adjustment method includes adjusting application force via adjusting a driveline disconnect clutch transfer function. The driveline disconnect clutch adjustment method further includes increasing a driveline disconnect clutch command and adjusting the driveline disconnect clutch transfer function based on an output of the torque sensor. The driveline disconnect clutch adjustment method further includes commanding the opening of a torque converter clutch. The driveline disconnect clutch adjustment method includes rotating the torque converter impeller via a driveline integrated starter / generator. The driveline disconnect clutch adjustment method includes where the driveline integrated starter / generator rotates at a speed that produces a threshold transmission oil pressure that maintains a transmission clutch in an applied condition. The driveline disconnect clutch adjustment method includes where the torque converter impeller rotates at a speed greater than a speed of the torque converter turbine wheel.

The methods and systems of 1 - 3 and 41 - 44 also provide a vehicle system comprising: an engine; a dual mass flywheel having a first side mechanically coupled to the engine; a driveline disconnect clutch having a first side mechanically coupled to a second side of the dual mass flywheel; a driveline integrated starter / generator (DISG) having a first side coupled to a second side of the driveline disconnect clutch; a transmission selectively coupled to the engine via the driveline disconnect clutch; and a controller having executable instructions stored in a nonvolatile memory to set an estimate of torque transmitted by the driveline disconnect clutch in response to a torque sensor output.

In one example, the vehicle system includes the engine not burning air and fuel. The vehicle system further includes rotating the DISG at a speed at which a threshold percentage of the DISG torque is transmitted to the transmission. The vehicle system further includes a torque converter having a torque converter clutch and additional instructions for opening the torque converter clutch while adjusting the estimate of the torque transmitted by the driveline disconnect clutch. The vehicle system further includes additional instructions for rotating an impeller of the torque converter at a higher speed than a turbine of the torque converter. The vehicle system further includes additional commands to increase a closing force applied to the driveline disconnect clutch.

The above-described methods and systems may derive torque at various locations of a torque converter. 45 - 48 describe an example of determining torque on the torque converter impeller and turbine wheel.

wobei K der Drehmomentwandler-K-Faktor ist, N_turbine die Drehmomentwandler-Turbinenraddrehzahl ist und N_impeller die Drehmomentwandler-Pumpenraddrehzahl ist und fn eine Funktion ist, die den K-Faktor beschreibt. Dann kann das Drehmoment am Drehmomentwandler-Pumpenrad beschrieben werden durch:

wobei T_imp das Drehmomentwandler-Pumpenraddrehmoment ist und wobei 1,558 ein Umwandlungsfaktor von ft-lbf auf Nm ist. Die obigen Beziehungen gelten für Drehzahlverhältnisse < 1.Regarding 45 is a function describing a torque converter K factor. The torque converter K-factor is related to the speed ratio of the torque converter impeller and turbine wheel. The K-factor of 45 can be expressed as:

where K is the torque converter K factor, N _{turbine is} the torque converter turbine _speed , and N _{impeller is} the torque converter impeller _speed and fn is a function describing the K factor. Then the torque on the torque converter impeller can be described by:

where T _{imp is} the torque converter impeller torque and where 1.558 is a conversion factor from ft-lbf to Nm. The above relationships apply to speed ratios <1.

wobei Capacity_Factor der Drehmomentwandler-Kapazitätsfaktor ist und wobei K der vorstehend beschriebene Drehmomentwandler-K-Faktor ist. Die in 46 beschriebene Funktion kann in Verbindung mit den in 47 und 48 beschriebenen Funktionen verwendet werden, um das Verhalten eines Drehmomentwandlers zu modellieren. Die individuellen Einträge, die die in 46 gezeigte Kurve bilden, können empirisch bestimmt und im Steuereinheitsspeicher gespeichert werden.Regarding 46 FIG. 12 is a function describing a torque converter capacity factor as a function of a ratio of torque converter impeller speed to torque converter turbine speed. FIG. The capacity factor is related to the K factor according to the following equation:

where Capacity_Factor is the torque converter capacity factor and where K is the torque converter K factor described above. In the 46 described function can be used in conjunction with in 47 and 48 functions described to model the behavior of a torque converter. The individual entries that are in 46 formed curve may be determined empirically and stored in the control unit memory.

wobei TR das Drehmomentwandler-Drehmomentverhältnis ist, fn eine Funktion ist, die das Drehmomentverhältnis beschreibt, N_turbine die Drehmomentwandler-Turbinenraddrehzahl ist und N_impeller die Drehmomentwandler-Pumpenraddrehzahl ist. Das Drehmomentwandler-Drehmomentverhältnis steht mit der Drehmomentwandler-Pumpenraddrehzahl über die folgende Gleichung in Beziehung: T_turbine = T_impeller·TR oder

Regarding 47 FIG. 12 is a function describing a torque converter torque ratio (TR) as a function of a ratio of torque converter impeller speed to torque converter turbine speed. In the 47 described function can be used in conjunction with in 46 and 48 functions described to model the behavior of a torque converter. The individual entries that are in 47 formed curve may be determined empirically and stored in the control unit memory. In the 47 shown function includes a Y-axis representing a torque converter torque ratio. The X-axis represents the ratio of the torque converter impeller to torque converter turbine speed. It can be seen that there is an inverse relationship between the torque converter torque ratio and the ratio of torque converter impeller torque to torque converter turbine speed. TR can be described as:

where TR is the torque converter torque ratio, fn is a function describing the torque _ratio , N _{turbine is} the torque converter turbine _speed , and N _{impeller is} the torque converter impeller _speed . The torque converter torque ratio is related to the torque converter impeller speed via the following equation: T _turbine = T _impeller · TR or

Regarding 48 is a function that has a torque converter capacity factor of 46 multiplied by the torque converter torque ratio of 47 as a function of a ratio of torque converter impeller speed to torque converter turbine speed.

In the 48 described function can be used in conjunction with in 46 and 47 functions described to model the behavior of a torque converter. The individual entries that are in 48 formed curve may be determined empirically and stored in the control unit memory. In the 48 The illustrated function includes a Y-axis representing a torque converter capacity factor multiplied by the torque converter torque ratio. The Y axis represents the ratio of the torque converter impeller to torque converter turbine speed.

In one example, the function is in 46 is indexed by the ratio of torque converter impeller speed to torque converter turbine speed and its output is multiplied by the torque converter impeller speed squared to provide an estimate of torque converter impeller torque. The function in 47 is indexed by the ratio of the torque converter impeller speed to the torque converter turbine speed and its output is determined by the function in 48 multiplied to provide an estimate of torque converter turbine torque. The torque across the torque converter is the difference between the torque converter impeller torque and the torque converter turbine torque. Of course, inverse operations for determining torque converter impeller speed and torque converter turbine speed may also be performed.

Consequently, the operation of a torque converter according to a model with the in 45 - 48 estimated functions are estimated. In particular, the torque converter may provide an estimate of torque converter impeller torque or torque converter turbine torque as an estimate of DISG torque or wheel torque because the torque converter is mechanically coupled to the DISG and the transmission.

As recognized by one of ordinary skill in the art, those in 4 - 44 described one or more of any number of processing strategies such. B. controlled by an event, controlled by an interrupt, multitasking, multithreading and the like. As such, various illustrated steps or functions in the illustrated sequence may be performed in parallel, or in some cases omitted. Likewise, the order of processing is not necessarily required to achieve the objects, features and advantages described herein, but is provided for ease of explanation and description. Although not explicitly illustrated, one skilled in the art will recognize that one or more of the illustrated steps or functions may be repeatedly performed depending on the particular strategy used.

This completes the description. Reading this by those skilled in the art would make many changes and modifications obvious without departing from the spirit and scope of the description. For example, Series 3, Series 4, Series 5, Series 6, V8, V10, and V12 engines operating on natural gas, gasoline, diesel, or alternative fuel configurations could take advantage of the present disclosure.

QUOTES INCLUDE IN THE DESCRIPTION

This list of the documents listed by the applicant has been generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Cited patent literature

• US 7066121 [0725, 0836]

Claims (20)

A method of operating a hybrid vehicle powertrain, comprising: Adjusting torque output of a driveline integrated starter / generator (DISG) in response to a difference between a desired driveline torque and an actual driveline torque during at least partially closing a driveline disconnect clutch. The method of claim 1, wherein a desired driveline torque is a desired torque converter impeller torque and wherein the actual driveline torque is an actual torque converter impeller torque. The method of claim 1, wherein the desired driveline torque is based on driver demand torque. The method of claim 1, further comprising adjusting a torque output of the DISG based on an estimate of the open-loop driveline disconnect clutch torque. The method of claim 4, wherein the driveline disconnect clutch torque estimate is based on a driveline disconnect clutch actuation command. The method of claim 1, further comprising starting an engine by closing the driveline disconnect clutch. The method of claim 6, further comprising starting the engine by supplying fuel and a spark to the engine before the driveline disconnect clutch is fully closed. A method of operating a hybrid vehicle powertrain, comprising: Adjusting torque output of a driveline integrated starter / generator (DISG) in response to a difference between a desired driveline torque and an actual driveline torque during at least partially closing a driveline disconnect clutch; and Adjusting a driveline disconnect clutch transfer function based on the difference between the desired driveline torque and the actual driveline torque. The method of claim 8, wherein the transfer function describes a driveline disconnect clutch torque as a function of a driveline disconnect clutch actuation force. The method of claim 8, further comprising starting an engine by at least partially closing the driveline disconnect clutch. The method of claim 10, further comprising starting the engine by supplying a spark and fuel to the engine before the driveline disconnect clutch is fully closed. The method of claim 11, further comprising completely closing the driveline disconnect clutch in response to the engine speed being substantially equal to the DISG speed for the first time since engine stop. The method of claim 8, wherein the desired driveline torque is based on an accelerator pedal input. The method of claim 8, wherein the actual driveline torque is based on an output of a torque sensor. A hybrid vehicle driveline system comprising: a driveline torque sensor; a driveline integrated starter / generator (DISG); an engine; a driveline disconnect clutch disposed in a driveline between the engine and the DISG; and a controller having executable nonvolatile commands for adjusting DISG torque output in response to a difference between a desired driveline torque and an output of the driveline torque sensor during driveline disconnect clutch actuation. The hybrid vehicle driveline system of claim 15, further comprising additional executable nonvolatile instructions for closing the driveline disconnect clutch at a first time that the engine speed after an engine start is substantially equal to the DISG speed. The hybrid vehicle driveline system of claim 15, further comprising additional executable nonvolatile commands to close the driveline disconnect clutch in response to a request to start the engine. Hybrid vehicle driveline system according to claim 15, further comprising additional executable nonvolatile instructions for adjusting a driveline disconnect clutch transfer function in response to the difference between the desired driveline torque and the output of the driveline torque sensor. The hybrid vehicle driveline system of claim 15, wherein the driveline torque sensor is positioned between a torque converter impeller and the DISG. The hybrid vehicle driveline system of claim 15, wherein the driveline torque sensor is positioned between a torque converter turbine wheel and a transmission gear set.

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