JP2013095155A - Vehicle control system and control device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a vehicle control system and a control device which can reliably start an internal combustion.SOLUTION: The control device 6 controls the internal combustion engine 7, a rotating electrical machine 10 and a clutch 9, and can implement first starting control which rotates an output shaft 20 of the internal combustion engine 7 by power from the rotating electrical machine 10 side while putting the clutch 9 in a slip condition, and then causes ignition by injecting a fuel to a combustion chamber 71 of the internal combustion engine 7 to start the internal combustion engine, and second starting control which causes ignition by injecting a fuel to the combustion chamber 71 of the internal combustion engine 7 in a state where the output shaft 71 of the internal combustion engine 7 stops rotation and rotates the output shaft 20, and then assists the rotation of the output shaft 20 by power from the rotating electrical machine 10 side through the clutch 9 to start the internal combustion engine. If a pressure inside the combustion chamber 7 detected by a detecting device 55 does not increase after the control device implements the second starting control and injects the fuel to the combustion chamber 71 to cause ignition, the control device 6 switches from the second starting control to the first starting control to start the internal combustion engine 7.

Description

  The present invention relates to a vehicle control system and a control device.

  As a conventional system for controlling a vehicle mounted on a vehicle, for example, Patent Document 1 discloses an internal combustion engine, particularly an internal combustion engine having a mechanism for directly injecting fuel into a drive train. There is disclosed a hybrid drive unit in which an engine is integrated and a separation clutch is disposed between the internal combustion engine and at least one electric drive unit.

JP 2009-527411 A

  By the way, the hybrid drive unit described in Patent Document 1 described above starts the engine by direct injection when the stop position of the crankshaft is 100 ° to 120 °, and controls otherwise. The separation clutch is controlled by the unit, and the engine is started by dynamic direct connection without starter support. For example, there is room for further improvement in terms of more reliable engine start.

  The present invention has been made in view of the above circumstances, and an object thereof is to provide a vehicle control system and a control device that can reliably start an internal combustion engine.

  In order to achieve the above object, a vehicle control system according to the present invention is capable of connecting a direct injection internal combustion engine and a rotating electrical machine, which are driving power sources for a vehicle, and the internal combustion engine and the rotating electrical machine. Combustion of the internal combustion engine after controlling a clutch, the internal combustion engine, the rotating electrical machine, and the clutch, and making the clutch in a slip state and rotating the output shaft of the internal combustion engine by power from the rotating electrical machine side A first start control for injecting and igniting fuel into the chamber to start the internal combustion engine; and injecting and igniting fuel into the combustion chamber of the internal combustion engine with the output shaft of the internal combustion engine stopped rotating A control device capable of performing a second start control for assisting the rotation of the output shaft by the power from the rotating electrical machine side via the clutch and starting the internal combustion engine after rotating the shaft; A detection device that detects a pressure in a combustion chamber of a combustion engine, and the control device performs the second start control, injects fuel into the combustion chamber and ignites, and then detects the detection device. When the pressure in the combustion chamber does not increase, the internal combustion engine is started by switching from the second start control to the first start control.

  In the vehicle control system, when the control device executes the second start control, injects fuel into the combustion chamber and ignites, the pressure in the combustion chamber detected by the detection device decreases. When the internal combustion engine is started by switching from the second start control to the first start control and the pressure in the combustion chamber detected by the detection device does not decrease, the second start control is continued and the second start control is continued. The internal combustion engine can be started.

  In the vehicle control system, the control device executes the second start control, injects fuel into the combustion chamber and ignites, and before the determination time set in advance elapses, When the detected pressure in the combustion chamber does not become larger than a preset determination value, the internal combustion engine can be started by switching from the second start control to the first start control.

  In the vehicle control system, when the second start control is executed, the control device injects fuel into the combustion chamber of the internal combustion engine and ignites the pressure in the combustion chamber detected by the detection device. , The assist of rotation of the output shaft of the internal combustion engine can be started by the power from the rotating electric machine side via the clutch regardless of the rotation of the output shaft of the internal combustion engine. .

  In the vehicle control system, the control device, as the second start control, injects fuel into the combustion chamber of the internal combustion engine after the clutch is slipped to such an extent that the output shaft of the internal combustion engine does not rotate. Then, after ignition and rotation of the output shaft of the internal combustion engine, the transmission torque of the clutch is increased to start the internal combustion engine.

  In order to achieve the above object, a control device according to the present invention includes a direct injection type internal combustion engine, a clutch, and driving power as a driving power source with respect to a power transmission path to driving wheels of a vehicle. A control device that controls a drive device arranged in order of a rotating electrical machine that is a source, and controls the internal combustion engine, the rotating electrical machine, and the clutch, puts the clutch into a slip state, and from the rotating electrical machine side First start control for rotating the output shaft of the internal combustion engine by power and then injecting and igniting fuel into the combustion chamber of the internal combustion engine to start the internal combustion engine, and rotation of the output shaft of the internal combustion engine stopped In this state, fuel is injected into the combustion chamber of the internal combustion engine and ignited to rotate the output shaft, and then the rotation of the output shaft is assisted by the power from the rotating electrical machine via the clutch to start the internal combustion engine. First When the second start control is executed, and after the fuel is injected into the combustion chamber and ignited, the pressure in the combustion chamber detected by the detection device does not increase. The internal combustion engine is started by switching from 2 start control to the first start control.

  The vehicle control system and the control device according to the present invention have an effect that the internal combustion engine can be reliably started.

FIG. 1 is a schematic configuration diagram of a vehicle control system according to the embodiment. FIG. 2 is a partial cross-sectional view including a combustion chamber of the engine of the vehicle control system according to the embodiment. FIG. 3 is a diagram for explaining the in-cylinder pressure of the engine of the vehicle control system according to the embodiment. FIG. 4 is a flowchart illustrating an example of control by the ECU of the vehicle control system according to the embodiment. FIG. 5 is a time chart illustrating an example of the operation of the vehicle control system according to the embodiment.

  Embodiments according to the present invention will be described below in detail with reference to the drawings. In addition, this invention is not limited by this embodiment. In addition, constituent elements in the following embodiments include those that can be easily replaced by those skilled in the art or those that are substantially the same.

[Embodiment]
1 is a schematic configuration diagram of a vehicle control system according to an embodiment, FIG. 2 is a partial cross-sectional view including a combustion chamber of an engine of the vehicle control system according to the embodiment, and FIG. 3 is a diagram of the vehicle control system according to the embodiment. FIG. 4 is a flowchart illustrating an example of control by the ECU of the vehicle control system according to the embodiment, and FIG. 5 is a time chart illustrating an example of operation of the vehicle control system according to the embodiment. It is.

The present embodiment is a so-called one-motor parallel hybrid type vehicle control system including one motor generator and one engine. The present embodiment is applied to a vehicle and typically includes the following components.
(1) A direct injection engine equipped with an in-cylinder pressure sensor (CPS).
(2) A clutch that can freely connect and disconnect the engine and the motor generator.

  In the present embodiment, when the engine is started with these components, for example, the first start control and the second start control are switched based on the in-cylinder pressure, so that the engine can be started more reliably according to the situation. Is realized.

  Specifically, as shown in FIG. 1, the vehicle control system 1 of this embodiment is a system that is mounted on a vehicle 2 and controls the vehicle 2. Typically, the engine of the vehicle 2 is stopped. An engine start control system that controls start from a state. The vehicle 2 is a so-called “hybrid vehicle” in which an engine 7 as an internal combustion engine and a motor generator 10 as a rotating electrical machine are mounted as a driving power source (prime mover) for driving the vehicle 2. More specifically, the vehicle 2 is a so-called 1MG + AT type “parallel hybrid vehicle” that includes one motor generator 10 and a transmission 12 that is an automatic transmission.

  The vehicle control system 1 includes a drive device 4 that drives the drive wheels 3 of the vehicle 2, a state detection device 5 that detects the state of the vehicle 2, and an ECU 6 as a control device that controls each part of the vehicle 2 including the drive device 4. With.

  The drive device 4 constitutes a parallel hybrid type power train in the vehicle 2, has one engine 7 and one motor generator 10, and drives the drive wheels 3 to rotate.

  The drive device 4 includes an engine 7, a damper mechanism 8, a K0 clutch 9 as a clutch, and a motor generator 10. Further, the drive device 4 includes a torque converter 11, a transmission 12, a propeller shaft 13, a differential gear 14, and a drive shaft 15. The torque converter 11 includes a lockup mechanism 16 and a fluid transmission mechanism 17. The transmission 12 includes a C1 clutch 18 and a transmission main body 19.

  The drive device 4 includes an engine 7, a damper mechanism 8, a K0 clutch 9, a motor generator 10, a lockup mechanism 16 for the torque converter 11, and a fluid transmission mechanism with respect to the transmission path of power to the drive wheels 3. 17, the C1 clutch 18 of the transmission 12, the transmission main body 19, the propeller shaft 13, the differential gear 14, and the drive shaft 15 are arranged so as to be able to transmit power to each other in this order. In this case, the drive device 4 includes a damper mechanism 8 and a K0 clutch in which a crankshaft 20 that is an output shaft (an internal combustion engine output shaft) of the engine 7 and a rotor shaft 21 that is an output shaft (motor output shaft) of the motor generator 10 are combined. 9 is connected. Further, in the drive device 4, the rotor shaft 21 and the drive wheel 3 are connected via a torque converter 11, a transmission 12, a propeller shaft 13, a differential gear 14, a drive shaft 15, and the like.

  More specifically, the engine 7 is a heat engine that converts fuel energy into mechanical work and outputs it as power by burning the fuel in the combustion chamber 71 (see FIG. 2). The engine 7 can generate mechanical power (engine torque) on the crankshaft 20 as the fuel burns, and can output this mechanical power from the crankshaft 20.

  Here, as shown in FIG. 2, the engine 7 of the present embodiment is a so-called multi-cylinder direct injection internal combustion engine. That is, the engine 7 directly injects the fuel spray 70 a into the combustion chamber 71 by the fuel injection device (injector) 70. The engine 7 is a so-called four-cycle engine that performs a series of four strokes while a piston 73 that is reciprocally movable in the cylinder bore 72 is reciprocated twice. The engine 7 typically has an intake pipe, a surge tank, an intake manifold, an intake port 75, etc. as the intake valve 74 is opened as the piston 73 descends from the top dead center of the intake stroke in the cylinder bore 72. The air is sucked into the combustion chamber 71 through the intake passage 76 (intake stroke). In the engine 7, the air is compressed by the piston 73 ascending in the cylinder bore 72 through the intake stroke bottom dead center (compression stroke). At this time, the engine 7 injects fuel from the fuel injection device 70 into the combustion chamber 71 in the intake stroke or compression stroke, and the fuel and air mix to form an air-fuel mixture. When the piston 73 approaches the top dead center of the compression stroke, the engine 7 ignites the air-fuel mixture by the spark plug 77, the air-fuel mixture ignites and burns, and lowers the piston 73 by the combustion pressure (expansion stroke). ). The air-fuel mixture after combustion rises again toward the intake stroke top dead center via the expansion stroke bottom dead center, and as the exhaust valve 78 is opened, the exhaust gas is converted into exhaust gas through the exhaust port 79. Released (exhaust stroke). The reciprocating motion of the piston 73 in the cylinder bore 72 is transmitted to the crankshaft 20 (see FIG. 1) via the connecting rod, where it is converted into a rotational motion and taken out as an output. The piston 73 reciprocates in the cylinder bore 72 as the crankshaft 20 rotates as the crankshaft 20 further rotates together with the counterweight due to the inertial force. By rotating the crankshaft 20 twice, the piston 73 reciprocates the cylinder bore 72 twice, during which a series of four strokes including an intake stroke, a compression stroke, an expansion stroke, and an exhaust stroke are performed, and once in the combustion chamber 71. Explosion takes place.

  The engine 7 can be switched between an operating state and a non-operating state regardless of whether the vehicle 2 is stopped or traveling. Here, the operating state of the engine 7 (the state in which the engine 7 is operated) is a state in which power to be applied to the drive wheels 3 is generated, and thermal energy generated by burning fuel in the combustion chamber 71 is converted to torque or the like. It is in a state of outputting in the form of mechanical energy. That is, the engine 7 generates power that burns fuel in the combustion chamber 71 and acts on the drive wheels 3 of the vehicle 2 in the operating state. On the other hand, the non-operating state of the engine 7, that is, the state where the operation of the engine 7 is stopped is a state where generation of power is stopped, fuel supply to the combustion chamber 71 is cut (fuel cut), and combustion is performed. This is a state in which no fuel is burned in the chamber 71 and no mechanical energy such as torque is output.

  Returning to FIG. 1, the K0 clutch 9 can connect the crankshaft 20 of the engine 7 and the rotor shaft 21 of the motor generator 10 via the damper mechanism 8. The K0 clutch 9 is in an engaged state in which the crankshaft 20 and the rotor shaft 21 are engaged so that power can be transmitted, a released state in which the engagement is released, and a slip state between the engaged state and the released state. Switching is possible. When the K0 clutch 9 is in an engaged state, the crankshaft 20 and the rotor shaft 21 are connected to each other via the damper mechanism 8 so as to be integrally rotatable, and power can be transmitted between the engine 7 and the motor generator 10. It becomes a state. On the other hand, when the K0 clutch 9 is in the released state, the crankshaft 20 and the rotor shaft 21 are disconnected, and the power transmission between the engine 7 and the motor generator 10 is cut off.

  Various clutches can be used as the K0 clutch 9, and for example, a friction type disk clutch device such as a wet multi-plate clutch or a dry single-plate clutch can be used. Here, the K0 clutch 9 is, for example, a hydraulic device that operates according to a clutch hydraulic pressure that is a hydraulic pressure of hydraulic oil supplied to the K0 clutch 9. The K0 clutch 9 is in a released state in which the engagement is completely released when the engagement force corresponding to the clutch oil pressure (the pressing force for engaging the clutch plate) is 0, and the slip state ( The semi-engaged state is brought into the fully engaged state. The transmission torque in the K0 clutch 9 is 0 in the disengaged state, becomes a magnitude corresponding to the engaging force in the slip state, and becomes maximum in the engaged state. The C1 clutch 18 and the lockup clutch 25 described below are substantially the same as the K0 clutch 9.

  The motor generator 10 is, for example, an AC synchronous motor. In the motor generator 10, a stator 22 as a stator is fixed to a case or the like, and a rotor 23 as a rotor is disposed radially inward of the stator 22 and coupled to the rotor shaft 21 so as to be integrally rotatable. The motor generator 10 has a function (power running function) as an electric motor that converts electric power supplied from a battery 24 as a power storage device via an inverter or the like into mechanical power, and an inverter that converts input mechanical power into electric power. This is a rotating electrical machine that also has a function (regenerative function) as a generator that charges the battery 24 via, for example. The motor generator 10 is driven by receiving AC power from the battery 24 via an inverter, for example, and generates mechanical power (motor torque) on the rotor shaft 21. The mechanical power is output from the rotor shaft 21. Is possible.

  The torque converter 11 is a kind of fluid coupling and is connected to the rotor shaft 21 of the motor generator 10. The torque converter 11 includes a lockup mechanism 16 that transmits power from the engine 7 or the motor generator 10 via a lockup clutch 25 and a fluid transmission mechanism 17 that transmits the hydraulic power via hydraulic oil (working fluid). The lockup mechanism 16 can connect the rotor shaft 21 and the output shaft (fluid transmission device output shaft) 26 of the torque converter 11 via the lockup clutch 25. The fluid transmission mechanism 17 includes a pump (pump impeller) 17p, a turbine (turbine runner) 17t, a stator 17s, a one-way clutch 17c, and the like, and is filled with hydraulic oil as a working fluid. The pump 17p is connected to the rotor shaft 21 so as to be integrally rotatable, and the turbine 17t is connected to the output shaft 26 so as to be integrally rotatable. The lock-up clutch 25 is in an engaged state in which the rotor shaft 21 and the turbine 17t are engaged to transmit power, a released state in which the engagement is released, and a slip state between the engaged state and the released state. Switching is possible. The torque converter 11 transmits the power from the engine 7 or the motor generator 10 to the output shaft 26 via the lockup mechanism 16 or the fluid transmission mechanism 17 in accordance with the state of the lockup clutch 25, and this output shaft 26 can be output.

  The transmission 12 transmits the power from the torque converter 11 to the transmission main body 19 via the C1 clutch 18, and the transmission main body 19 changes the speed and outputs it to the drive wheel 3 side. The C1 clutch 18 can connect the output shaft 26 of the torque converter 11 and the drive wheel 3 via the transmission main body 19, the propeller shaft 13, the differential gear 14, the drive shaft 15, and the like. Here, the C1 clutch 18 is in an engaged state in which the output shaft 26 of the torque converter 11 and the input shaft 27 of the transmission main body 19 are engaged so as to be able to transmit power, a released state in which this engagement is released, It is possible to switch to a slip state between a state and a released state. The transmission main body 19 is a so-called stepped automatic transmission (AT), continuously variable automatic transmission (CVT), multi-mode manual transmission (MMT), sequential manual transmission (SMT), dual clutch transmission (DCT), or the like. It is an automatic transmission. Here, for example, a stepped automatic transmission is applied to the transmission main body 19.

  The differential gear 14 transmits the power from the propeller shaft 13 to each drive wheel 3 via each drive shaft 15. The differential gear 14 absorbs a difference in rotational speed between the center side of the turn, that is, the inner drive wheel 3 and the outer drive wheel 3 that occurs when the vehicle 2 turns.

  The drive device 4 configured as described above uses the power generated by the engine 7 from the crankshaft 20 to the damper mechanism 8, the K0 clutch 9, the rotor shaft 21, the torque converter 11, the transmission 12, the propeller shaft 13, and the differential gear. 14, and can be transmitted to the drive wheel 3 via the drive shaft 15. Further, the drive device 4 transmits the power generated by the motor generator 10 from the rotor shaft 21 via the torque converter 11, the transmission 12, the propeller shaft 13, the differential gear 14, and the drive shaft 15, without passing through the K0 clutch 9. Can be transmitted to the drive wheel 3. As a result, the vehicle 2 can travel by generating a driving force [N] on the ground contact surface between the driving wheel 3 and the road surface.

  The state detection device 5 detects the state of the vehicle 2, and detects various state quantities and physical quantities representing the state of the vehicle 2, operating states of switches, and the like. The state detection device 5 is electrically connected to the ECU 6 and can exchange information such as a detection signal, a drive signal, and a control command with each other. The state detection device 5 includes, for example, an accelerator opening sensor 50, a brake sensor 51, a vehicle speed sensor 52, a crank angle sensor 53, a charge state detector 54, and the like. The accelerator opening sensor 50 detects an accelerator opening corresponding to an operation amount (accelerator operation amount, acceleration request operation amount) of the accelerator pedal of the vehicle 2 by the driver. The brake sensor 51 detects a master cylinder pressure or a brake depression force corresponding to an operation amount (brake operation amount, braking request operation amount) of the vehicle 2 by the driver. The vehicle speed sensor 52 detects the vehicle speed that is the traveling speed of the vehicle 2. The crank angle sensor 53 detects a crank angle that is a rotation angle of the crankshaft 20. The ECU 6 determines the intake stroke, compression stroke, expansion stroke, and exhaust stroke in each cylinder of the engine 7 based on the crank angle, and calculates the engine rotational speed that is the rotational speed (rotational speed) of the crankshaft 20. be able to. The state of charge detector 54 detects the state of charge SOC according to the amount of charge (charge amount) of the battery 24, the battery voltage, and the like.

  The ECU 6 is a control unit that performs overall control of the vehicle control system 1 and controls the engine 7 and the motor generator 10 in a coordinated manner. The ECU 6 is an electronic circuit mainly composed of a known microcomputer including a CPU, a ROM, a RAM, and an interface. The ECU 6 is electrically connected to the state detection device 5, and is also electrically connected to the fuel injection device 70 of the engine 7, the spark plug 77, the throttle device, the inverter of the motor generator 10, the battery 24, and the like. Further, the ECU 6 is connected to the K0 clutch 9, the lockup clutch 25, the C1 clutch 18, the transmission main body 19, and the like via the hydraulic control device 28, and controls these operations via the hydraulic control device 28. The ECU 6 receives an electrical signal corresponding to the detection result detected by the state detection device 5, and outputs to each part of the drive device 4 such as the engine 7, the inverter of the motor generator 10, and the hydraulic control device 28 according to the input detection result. Drive signals are output to control these drives.

  Here, the hydraulic control device 28 uses the hydraulic pressure of the working oil (oil) as the working fluid to engage the shifting operation of the transmission main body 19 and the engagement elements such as the K0 clutch 9, the lockup clutch 25, and the C1 clutch 18.・ Controls the release / slip operation. The hydraulic control device 28 includes various known hydraulic control circuits controlled by the ECU 6, and includes, for example, a plurality of oil passages, an oil reservoir, an oil pump, and a plurality of electromagnetic valves. The hydraulic control device 28 controls the flow rate or hydraulic pressure of the hydraulic oil supplied to each part of the drive device 4 in accordance with a signal from the ECU 6.

  The ECU 6 controls the throttle device of the engine 7 based on, for example, the accelerator opening, the vehicle speed, etc., adjusts the throttle opening of the intake passage 76, adjusts the intake air amount, and injects fuel in response to the changes. The output of the engine 7 is controlled by controlling the amount and adjusting the amount of the air-fuel mixture filled in the combustion chamber 71. Further, the ECU 6 controls the hydraulic control device 28 based on, for example, the accelerator opening degree, the vehicle speed, etc., and the gear shift operation of the transmission main body 19 and the engagement / release of the K0 clutch 9, the lockup clutch 25, the C1 clutch 18, etc.・ Slip operation is controlled.

  In the vehicle control system 1 configured as described above, the ECU 6 controls the drive device 4 to use the engine 7 and the motor generator 10 together or selectively, thereby allowing the vehicle 2 to travel in various travel modes. it can.

  For example, the ECU 6 puts the K0 clutch 9 into an engaged state (K0 clutch ON) and operates the engine 7 to output power (engine torque) output from the engine 7 of the engine 7 and the motor generator 10 that are driving power sources. Only to the drive wheels 3. At this time, the C1 clutch 18 is in an engaged state (C1 clutch ON). As a result, the vehicle control system 1 can realize the “engine running” mode. Therefore, the vehicle 2 can travel using only the engine 7 of the traveling power source.

  Further, the ECU 6, for example, in the state where the K0 clutch 9 is engaged (K0 clutch ON) and the engine 7 is operated as described above, according to the required driving force and the storage state SOC of the battery 24, the motor generator 10 The power output from the engine 7 and the power output from the motor generator 10 (motor torque) are integrated and transmitted to the drive wheels 3. At this time, the C1 clutch 18 is in an engaged state (C1 clutch ON). Thereby, the vehicle control system 1 can implement the “HV traveling” mode. Therefore, the vehicle 2 can travel using the engine 7 and the motor generator 10 together.

  Further, for example, the ECU 6 puts the K0 clutch 9 in a disengaged state (K0 clutch OFF) and stops the engine 7 to be in an inoperative state. Only the power output from the motor generator 10 out of the generator 10 is transmitted to the drive wheels 3. At this time, the C1 clutch 18 is in an engaged state (C1 clutch ON). Further, since the engine 7 is in an inoperative state and the K0 clutch 9 is in a released state, the rotation of the crankshaft 20 is also stopped. Thereby, the vehicle control system 1 can implement the “EV traveling” mode. Therefore, the vehicle 2 can travel using only the motor generator 10 of the traveling power source. At this time, the vehicle 2 is basically in a state where the crankshaft 20 and the rotor shaft 21 are mechanically separated by the K0 clutch 9, and the rotational resistance of the engine 7 is not activated.

  For example, the ECU 6 controls the motor generator 10 when the vehicle 2 travels at a reduced speed, and regenerates power by the motor generator 10 using the power transmitted from the drive wheels 3 to the rotor shaft 21. The mechanical power (negative motor torque) generated in 21 is transmitted to the drive wheel 3. At this time, the C1 clutch 18 is in an engaged state (C1 clutch ON). Thereby, the vehicle control system 1 can implement the “regenerative travel” mode. Therefore, the vehicle 2 can be decelerated while being regeneratively braked by the motor generator 10.

  For example, when the engine 7 is started from a state where the engine 7 is in an inoperative state and the rotation of the crankshaft 20 is stopped, the ECU 6 can start the engine 7 in two different start modes. The ECU 6 can selectively use K0 start control as the first start control and ignition start control as the second start control depending on the situation.

  When executing the K0 start control, the ECU 6 uses the motor generator 10 as a starter motor of the engine 7 to start the engine 7. In this case, the ECU 6 executes the K0 start control as follows. That is, the ECU 6 controls the engine 7, the motor generator 10, and the K0 clutch 9. First, the K0 clutch 9 is set in the slip state and the crankshaft 20 of the engine 7 is rotated (cranking) by power from the motor generator 10 side. Let That is, the ECU 6 rotates the crankshaft 20 with the K0 clutch 9 in the slip state and using a part of the power output from the motor generator 10 as the cranking torque (starting torque) of the crankshaft 20. Then, after rotating the crankshaft 20, the ECU 6 injects fuel from the fuel injection device 70 into the combustion chamber 71 and ignites the spark plug 77 to start the engine 7 (K0). Start). After that, the ECU 6 is in an engaged state in which the K0 clutch 9 is completely engaged when the engine speed becomes a speed at which autonomous operation is possible and the engine 7 is completely started and the engine speed and the motor speed are substantially synchronized. To do.

  Further, since the engine 7 is an in-cylinder direct injection internal combustion engine, the ECU 6 can also start the engine 7 by executing the ignition start control as described below. That is, the ECU 6 controls the engine 7 to inject fuel from the fuel injection device 70 into the combustion chamber 71 in a state where the rotation of the crankshaft 20 is stopped, and ignite by the spark plug 77 to rotate the crankshaft 20 to rotate the engine 7. Start. Here, the ECU 6 controls the engine 7, the motor generator 10, and the K0 clutch 9, and first stops in the combustion chamber 71 of the engine 7, typically in the expansion stroke, with the rotation of the crankshaft 20 stopped. Fuel is injected into the combustion chamber 71 of the cylinder for ignition, and rotation of the crankshaft 20 is started by the combustion energy of the fuel. Thereafter, the ECU 6 increases the transmission torque of the K0 clutch 9 in a state where the crankshaft 20 starts rotating due to combustion, and the crankshaft 20 is rotated by a part of the power from the motor generator 10 side via the K0 clutch 9. To start the engine 7 (ignition start). After that, the ECU 6 is in an engaged state in which the K0 clutch 9 is completely engaged when the engine speed becomes a speed at which autonomous operation is possible and the engine 7 is completely started and the engine speed and the motor speed are substantially synchronized. To do.

  At this time, in this ignition start control, the ECU 6 sets the torque capacity of the K0 clutch 9 to a standby torque capacity that is large enough that the crankshaft 20 does not start rotating until the ignition of the air-fuel mixture is completed. . That is, as the ignition start control, the ECU 6 sets the K0 clutch 9 to the slip state so that the crankshaft 20 does not rotate until ignition is completed, and sets the torque capacity of the K0 clutch 9 as the standby torque capacity. After that, the ECU 6 injects fuel into the combustion chamber 71 to ignite and rotate the crankshaft 20, and then increases the transmission torque (torque capacity) of the K0 clutch 9 to start the engine 7. As a result, the vehicle control system 1 immediately increases the torque capacity of the K0 clutch 9 to the ignition start assist torque capacity as soon as combustion starts and the rotation of the crankshaft 20 starts. Assist torque can be transmitted to 20. As a result, the vehicle control system 1 can start the engine 7 more reliably and quickly. The standby torque capacity may be zero. In this case, as the ignition start control, the ECU 6 injects fuel into the combustion chamber 71 in a state where the rotation of the crankshaft 20 is stopped, ignites and rotates the crankshaft 20, and then puts the K0 clutch 9 in the slip state. The transmission torque (torque capacity) is increased and the engine 7 is started.

  The ECU 6 controls the hydraulic control device 28 to adjust the K0 pressure, which is the clutch hydraulic pressure supplied to the K0 clutch 9, and to adjust the torque capacity of the K0 clutch 9, so that the K0 at the start of the engine 7 is adjusted. The transmission torque of the clutch 9 (hereinafter sometimes referred to as “K0 torque”) can be adjusted. Here, when comparing the K0 start and the ignition start, the torque capacity of the K0 clutch 9 is relatively larger at the K0 start and relatively smaller at the ignition start. . In other words, the assist torque of the crankshaft 20 in the ignition start control is equal to the crankshaft 20 rotation in the K0 start control because the crankshaft 20 starts rotating using the combustion energy in the combustion chamber 71 in the ignition start. Less than the cranking torque. For this reason, the transmission torque capacity of the K0 clutch 9 can be relatively smaller in the ignition start control than in the case of the K0 start control. Therefore, the vehicle control system 1 can relatively reduce the load of the motor generator 10 by suppressing power consumption in the ignition start control. Here, the ECU 6 is able to start ignition in accordance with, for example, an estimated value of the air amount in the combustion chamber 71, a stop position (stop crank angle) of the crankshaft 20, an elapsed time after the engine stops, and the like. Actively perform ignition start control. Thereby, the vehicle control system 1 can suppress power consumption and improve fuel consumption performance.

  By the way, when the vehicle control system 1 performs the ignition start described above, when the crankshaft 20 starts rotating, the vehicle control system 1 distinguishes whether the rotation is caused by fuel combustion energy or K0 torque. It is preferable to change the starting pattern by changing the above. However, there is a possibility that the ECU 6 cannot properly distinguish between the rotation start due to the combustion energy of the fuel and the rotation start due to the K0 torque, based on the detection result by the rotation speed sensor such as the crank angle sensor 53.

  Therefore, the vehicle control system 1 of the present embodiment is configured such that the state detection device 5 includes an in-cylinder pressure sensor 55 as a detection device. For example, the ECU 6 determines whether combustion has started based on the detection result by the in-cylinder pressure sensor 55. The engine is more reliably started by changing the starting pattern.

  The in-cylinder pressure sensor 55 of this embodiment detects an in-cylinder pressure that is a pressure in the combustion chamber 71. The ECU 6 switches between the K0 start control and the ignition start control based on the in-cylinder pressure detected by the in-cylinder pressure sensor 55.

  Specifically, the ECU 6 executes the ignition start control, injects fuel into the combustion chamber 71 and ignites, and then changes from the ignition start control to the K0 start control when the in-cylinder pressure detected by the in-cylinder pressure sensor 55 does not increase. The engine 7 is started by switching.

  More specifically, the ECU 6 executes the ignition start control, and injects fuel into the combustion chamber 71 of the cylinder stopped in the expansion stroke and ignites it. The in-cylinder pressure of the combustion chamber 71 detected by the in-cylinder pressure sensor 55 is detected. To monitor. When the in-cylinder pressure detected by the in-cylinder pressure sensor 55 is reduced after the ignition start control is executed and fuel is injected into the combustion chamber 71 and ignited, the ECU 6 switches the ignition start control to the K0 start control and switches the engine 7 on. Start. On the other hand, when the in-cylinder pressure detected by the in-cylinder pressure sensor 55 does not decrease, the ECU 6 continues the ignition start control and starts the engine 7.

  Here, FIG. 3 represents an example of the in-cylinder pressure at the start of ignition. In FIG. 3, the horizontal axis is the crank angle, and the vertical axis is the in-cylinder pressure. In FIG. 3, the solid line L11 represents the in-cylinder pressure during proper combustion, and the dotted line L12 represents the in-cylinder pressure during non-combustion. In FIG. 3, the crank angle θ1 represents a position before start processing, the crank angle θ2 represents a position where rotation can be detected by a rotation speed sensor or the like, and the crank angle θ3 represents an exhaust valve 78 opening position. As is apparent from this figure, when the combustion is properly generated in the combustion chamber 71 by the ignition start, the in-cylinder pressure rises as indicated by a solid line L11. On the other hand, when combustion does not properly occur in the combustion chamber 71 and the rotation of the crankshaft 20 is started by K0 torque or the like, typically, fuel is not combusted in the combustion chamber 71, and Since the piston 73 stopped in the expansion stroke descends and the volume of the combustion chamber 71 increases, the in-cylinder pressure tends to decrease as indicated by the dotted line L12.

  Therefore, as shown by the solid line L11 in FIG. 3, the ECU 6 appropriately ignites and burns the fuel (air mixture) in the combustion chamber 71 when the in-cylinder pressure does not decrease and rises, and the combustion energy of the fuel It can be estimated that the crankshaft 20 has started to rotate properly. In this case, the ECU 6 continues the ignition start control as it is and starts the engine 7.

  On the other hand, when the in-cylinder pressure decreases, for example, when [in-cylinder pressure <in-cylinder pressure before start × 0.95] is satisfied, the ECU 6 uses the fuel (air mixture) as shown by a dotted line L12 in FIG. Although ignited, the fuel in the combustion chamber 71 is not properly ignited and combusted. Therefore, it can be estimated that the crankshaft 20 has started to rotate by the K0 torque, not by the combustion energy of the fuel. In this case, when the fuel is not properly ignited or combusted in the combustion chamber 71, the ECU 6 generates a shock at the time of starting due to abnormal combustion or fails to start (engine stall) even if ignition start is continued. Therefore, the ignition start control is stopped, and the engine 7 is started by switching to the K0 start control.

  In addition, when the vehicle control system 1 starts ignition, for example, if the crankshaft 20 starts rotating before the fuel is ignited and combustion is started properly, the amount of air in the cylinder changes or the exhaust valve 78 is started. If the ignition start is continued in the state as it is, not only will the start fail, but there is a risk of exhaust performance deterioration and catalyst deterioration.

  On the other hand, in the vehicle control system 1, as described above, the ECU 6 monitors the in-cylinder pressure detected by the in-cylinder pressure sensor 55 at the start of ignition, so that the rotation of the crankshaft 20 is caused by the combustion energy of the fuel. Or whether it is due to the K0 torque, can be quickly and accurately distinguished. As a result, the ECU 6 can accurately determine the presence / absence of combustion when starting the ignition, and if it is determined that the fuel is combusting properly, the engine 7 is started as it is by starting the ignition. be able to. On the other hand, if the ECU 6 determines that the fuel is not combusting properly, it shifts to the K0 start, thereby causing a shock due to abnormal combustion, start failure, exhaust performance deterioration, catalyst deterioration, etc. during engine start. Therefore, the engine 7 can be started properly.

  Here, the ECU 6 preferably executes the ignition start control, injects fuel into the combustion chamber 71 and ignites, and then detects the cylinder detected by the cylinder pressure sensor 55 until a predetermined determination time elapses. When the internal pressure does not become larger than a preset determination value, it is preferable to start the engine 7 by switching from the ignition start control to the K0 start control. Here, for example, the determination time is set according to the time during which the fuel (air mixture) in the combustion chamber 71 is ignited and then properly ignited and the flame propagates. In addition, the determination value is set according to an in-cylinder pressure that is slightly higher than the in-cylinder pressure at the time of ignition, for example. The determination time and the determination value are preset according to the actual vehicle evaluation and stored in the storage unit of the ECU 6.

  If the in-cylinder pressure detected by the in-cylinder pressure sensor 55 does not become larger than the determination value even after the determination time has elapsed after injecting fuel into the combustion chamber 71 and igniting, that is, the in-cylinder pressure is as expected. If it does not rise, it can be presumed that although it has ignited, ignition has failed or it has misfired. In this case, the ECU 6 stops the ignition start control, switches to the K0 start control, and starts the engine 7 as described above.

  As a result, the ECU 6 can determine misfire when performing ignition start, and if it is determined that misfire has occurred, the ECU 6 shifts to K0 start so that a shock may occur due to abnormal combustion during engine start. Thus, the engine 7 can be started more reliably without failing in starting.

  Furthermore, the ECU 6 of the present embodiment more preferably, when executing the ignition start control, after injecting fuel into the combustion chamber 71 and igniting, the in-cylinder pressure detected by the in-cylinder pressure sensor 55 increases. Regardless of the rotation of the crankshaft 20, it is preferable that the K0 clutch 9 be in a slip state to immediately start assisting the rotation of the crankshaft 20 by the power from the motor generator 10 side.

  In this case, when the in-cylinder pressure detected by the in-cylinder pressure sensor 55 increases, the ECU 6 detects the start of combustion in the combustion chamber 71 earlier than when the rotation of the crankshaft 20 is detected by the crank angle sensor 53 or the like. can do. Even before the rotation of the crankshaft 20 is detected, the ECU 6 properly ignites and burns the fuel in the combustion chamber 71 and the in-cylinder pressure rises. For example, immediately after the ECU 6 becomes larger than the above-described determination value. The hydraulic pressure control device 28 is controlled to increase the K0 pressure supplied to the K0 clutch 9, and the torque capacity of the K0 clutch 9 is increased from the standby torque capacity to the ignition start assist torque capacity.

  Thus, the vehicle control system 1 outputs the fuel injection and ignition signal to the engine 7 at the start of ignition, and before the rotation of the crankshaft 20 is detected, the fuel in the combustion chamber 71 is started before the rotation is started. Can be read in advance when it is confirmed that the ignition is properly ignited and combustion is started, and the rotation of the crankshaft 20 can be immediately assisted by the K0 torque. As a result, the vehicle control system 1 can shorten the start time of the engine 7 and can start the engine 7 more reliably and quickly.

  Next, an example of control by the ECU 6 in the vehicle control system 1 will be described with reference to the flowchart of FIG. Note that these control routines are repeatedly executed at a control cycle of several ms to several tens of ms.

  First, the ECU 6 determines whether or not the ignition start is being performed by executing the ignition start control based on the detection result by the state detection device 5 and the operating state of each part (ST1). When it is determined that the ignition start is not being performed (ST1: No), the ECU 6 ends the current control cycle and shifts to the next control cycle.

  When it is determined that the ignition start is being performed (ST1: Yes), the ECU 6 executes the ignition start control, injects fuel into the combustion chamber 71 and ignites, and then the cylinder pressure detected by the cylinder pressure sensor 55 is detected. It is determined whether or not it has decreased (ST2).

  When it is determined that the in-cylinder pressure has decreased (ST2: Yes), the ECU 6 stops the ignition start control, switches to the K0 start control, shifts to the K0 start (ST3), ends the current control cycle, and Transition to the control cycle. In this case, the ECU 6 controls the hydraulic control device 28 to increase the K0 pressure supplied to the K0 clutch 9 and increase the torque capacity of the K0 clutch 9 from the standby torque capacity to the K0 start cranking torque capacity. By this. The ECU 6 can crank the crankshaft 20 with the K0 torque, and can start the engine 7 with the K0 start.

  When the ECU 6 determines in ST2 that the in-cylinder pressure has not decreased (ST2: No), the ignition start is continued (ST4), and the in-cylinder pressure detected by the in-cylinder pressure sensor 55 increases and becomes greater than the determination value. It is determined whether or not (ST5).

  When the ECU 6 determines that the in-cylinder pressure has increased and becomes larger than the determination value (ST5: Yes), the ECU 6 controls the hydraulic control device 28 to increase the K0 pressure supplied to the K0 clutch 9, and the torque capacity of the K0 clutch 9 Is increased from the standby torque capacity to the ignition start assist torque capacity (ST6), the current control cycle is terminated, and the next control cycle is started. Thereby, the ECU 6 can assist the rotation of the crankshaft 20 by the K0 torque, and can start the engine 7 by the ignition start.

  When the ECU 6 determines that the in-cylinder pressure has not increased and is not greater than the determination value (ST5: No), whether or not the determination time Td has elapsed since the fuel was injected into the combustion chamber 71 and ignited. Is determined (ST7). When it is determined that the determination time Td has not elapsed (ST7: No), the ECU 6 returns to ST5 and repeats the subsequent processes.

  When it is determined that the determination time Td has elapsed (ST7: Yes), the ECU 6 stops the ignition start control, switches to the K0 start control, shifts to the K0 start (ST8), ends the current control cycle, and next time Shift to the control cycle. In this case, the ECU 6 executes almost the same control as ST3.

  Next, an example of operation | movement of the vehicle control system 1 comprised as mentioned above with reference to the time chart of FIG. 5 is demonstrated. In FIG. 5, the horizontal axis is the time axis, and the vertical axis is the K0 pressure set value, the rotation speed, and the in-cylinder pressure. In FIG. 5, the solid line L21 represents the K0 pressure set value, the solid line L22 represents the motor speed, the solid line L23 represents the engine speed, and the solid line L24 represents the in-cylinder pressure. FIG. 5 shows a case where the ignition start control is executed.

  When executing the ignition start control, the ECU 6 first controls the hydraulic control device 28 to generate the precharge pressure Pqf, and then the crankshaft 20 rotates the K0 pressure of the K0 clutch 9 as shown in FIG. The pressure is adjusted to the standby hydraulic pressure P1 corresponding to the standby torque that does not start, and the torque capacity of the K0 clutch 9 is set as the standby torque capacity. Then, the ECU 6 controls the engine 7 at time t1, injects fuel into the combustion chamber 71, and starts ignition. At this time, the ECU 6 controls the motor generator 10 to keep the motor speed at a speed at which the engine can be started. Then, the ECU 6 controls the hydraulic control device 28 at time t2 when the in-cylinder pressure becomes larger than the determination value, and increases the K0 pressure of the K0 clutch 9 to the ignition start assist hydraulic pressure P2 corresponding to the assist torque at the start of ignition. The torque capacity of the K0 clutch 9 is set as the ignition start assist torque capacity. In this case, the ECU 6 can start assisting the rotation of the crankshaft 20 earlier than when the rotation of the crankshaft 20 is detected by the crank angle sensor 53 or the like, for example, as indicated by a dotted line L25. The ECU 6 assists the rotation of the crankshaft 20 by a part of the power from the motor generator 10 side and starts the engine 7 completely. Thereafter, the ECU 6 controls the hydraulic control device 28 to control the K0 clutch 9 at a time t3 when the engine speed becomes a speed at which autonomous operation is possible and the engine 7 is completely started and the engine speed and the motor speed are substantially synchronized. The K0 pressure is increased to the engagement hydraulic pressure P3, and the K0 clutch 9 is completely engaged.

  The vehicle control system 1 and the ECU 6 according to the embodiment described above can accurately determine the presence or absence of combustion based on the in-cylinder pressure detected by the in-cylinder pressure sensor 55 when starting ignition. The engine 7 can be reliably started by switching the ignition start and the K0 start more appropriately according to the situation.

  The vehicle control system and the control device according to the above-described embodiments of the present invention are not limited to the above-described embodiments, and various modifications can be made within the scope described in the claims.

  The vehicle control system 1 described above may be configured without the damper mechanism 8 or the like.

  In the vehicle control system 1 described above, a starter is provided in the engine 7 itself, the crankshaft 20 of the engine 7 is rotated (cranking) by the starter, and the engine 7 is started (starter start control). May be used in combination.

  The ECU 6 described above not only switches the ignition start and the K0 start by switching the K0 pressure and the like based on the detection result by the in-cylinder pressure sensor 55, but also the injection amount by the fuel injection device 70 when the engine 7 is started, The retard amount of the ignition timing by the spark plug 77 may be changed.

DESCRIPTION OF SYMBOLS 1 Vehicle control system 2 Vehicle 3 Drive wheel 4 Drive device 5 State detection device 6 ECU (control device)
7 Engine (Internal combustion engine)
9 K0 clutch (clutch)
10 Motor generator (rotary electric machine)
20 Crankshaft (output shaft)
28 Hydraulic control device 55 In-cylinder pressure sensor (detection device)
71 Combustion chamber

Claims (6)

An in-cylinder direct injection internal combustion engine and a rotating electrical machine, which are power sources for driving the vehicle,
A clutch capable of connecting the internal combustion engine and the rotating electrical machine;
The internal combustion engine, the rotating electrical machine, and the clutch are controlled, the clutch is brought into a slip state, the output shaft of the internal combustion engine is rotated by power from the rotating electrical machine side, and then fuel is supplied to the combustion chamber of the internal combustion engine. A first start control for injecting and igniting to start the internal combustion engine; and in a state where the rotation of the output shaft of the internal combustion engine is stopped, fuel is injected into the combustion chamber of the internal combustion engine to ignite and rotate the output shaft. And a second start control that assists rotation of the output shaft with power from the rotating electrical machine side via the clutch and starts the internal combustion engine,
A detection device for detecting the pressure in the combustion chamber of the internal combustion engine,
The control device executes the second start control, injects fuel into the combustion chamber and ignites, and then, when the pressure in the combustion chamber detected by the detection device does not increase, the control device starts from the second start control. Switching to the first start control and starting the internal combustion engine,
Vehicle control system. The control device executes the second start control, injects fuel into the combustion chamber and ignites, and then when the pressure in the combustion chamber detected by the detection device decreases, the control device starts from the second start control. When the internal combustion engine is started by switching to the first start control and the pressure in the combustion chamber detected by the detection device does not drop, the second start control is continued and the internal combustion engine is started.
The vehicle control system according to claim 1. The control device executes the second start control, injects fuel into the combustion chamber and ignites, and then detects a pressure in the combustion chamber detected by the detection device before a predetermined determination time elapses. If not greater than a preset determination value, the internal combustion engine is started by switching from the second start control to the first start control;
The vehicle control system according to claim 1 or 2. When the control device executes the second start-up control, after the fuel is injected into the combustion chamber of the internal combustion engine and ignited, when the pressure in the combustion chamber detected by the detection device rises, the internal combustion engine Regardless of the rotation of the output shaft of the engine, start assisting the rotation of the output shaft of the internal combustion engine by power from the rotating electrical machine side via the clutch,
The vehicle control system according to any one of claims 1 to 3. In the second start control, the control device sets the clutch to a slip state so that the output shaft of the internal combustion engine does not rotate, and then injects and ignites fuel into the combustion chamber of the internal combustion engine to ignite the internal combustion engine. The internal combustion engine is started by increasing the transmission torque of the clutch after rotating the output shaft;
The vehicle control system according to any one of claims 1 to 4. A driving device arranged in the order of an in-cylinder direct injection internal combustion engine, which is a driving power source, a clutch, and a rotating electric machine, which is a driving power source, is controlled with respect to a power transmission path to the driving wheels of the vehicle. A control device,
The internal combustion engine, the rotating electrical machine, and the clutch are controlled, the clutch is brought into a slip state, the output shaft of the internal combustion engine is rotated by power from the rotating electrical machine side, and then fuel is supplied to the combustion chamber of the internal combustion engine. A first start control for injecting and igniting to start the internal combustion engine; and in a state where the rotation of the output shaft of the internal combustion engine is stopped, fuel is injected into the combustion chamber of the internal combustion engine to ignite and rotate the output shaft. A second start control for assisting the rotation of the output shaft by the power from the rotating electrical machine side via the clutch and starting the internal combustion engine;
Further, after executing the second start control, injecting fuel into the combustion chamber and igniting, when the pressure in the combustion chamber detected by the detection device does not increase, the second start control to the first start control The internal combustion engine is started by switching to
Control device.

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