DE102012218259A1 - Method for controlling charging of battery of e.g. inline-4 engine for supplying energy to pump of motor car, involves charging battery via auxiliary generator when charging condition of battery lies below high threshold value - Google Patents

Abstract

The method involves conducting intake air through a throttle bypass (204) around a throttle (62) and through a turbine (206) for driving an auxiliary generator (210), and charging a battery (212) via the auxiliary generator when a charging condition of the battery lies below a high threshold value. The valve is arranged in an intake channel of an engine (10). A mechanically driven primary generator (214) is used for charging the battery in addition to the auxiliary generator only when the charging condition of the battery is smaller than a low threshold value or when a vehicle runs slow. An independent claim is also included for a system controlling charging of a battery of a multi-cylinder engine.

Description

The present application relates to methods and systems for an engine system including a throttle-valve turbine generator.

Some engine systems may include devices such as throttle turbine generators to use energy from a pressure differential across a throttle valve that is otherwise wasted in an intake passage of an engine. In some examples, the throttle-turbine generator includes a turbine that is mechanically coupled to a generator that can generate power that is supplied to a battery of the engine. By charging the battery with such a generator, the fuel economy of the engine system can be improved as compared to charging the battery with a motor-driven generator.

However, the turbine-powered generator may not provide enough power to sustain the battery charge under some conditions. Thus, the engine system may include a turbine-operated generator (eg, a throttle-valve turbine generator) and a motor-driven generator. With such a configuration, the fuel economy of the engine may decrease when the engine-operated generator is used, thereby reducing the overall efficiency of the engine system.

The inventors of the present invention have recognized the above problem and have devised a solution to at least partially solve it. Thus, a method for an engine is disclosed. In one example, when a state of charge of a battery is below a threshold, the method includes directing intake air through a throttle bypass around a throttle disposed in an intake passage of the engine and through a turbine for driving an auxiliary generator. Furthermore, the method includes charging the battery via the additional generator.

In such an approach, the battery may be charged by the auxiliary generator when the state of charge of the battery is below the threshold. The threshold value may be a first, high threshold, which corresponds for example to a maximum state of charge of the battery. In some examples, a mechanically driven primary generator for charging the battery in addition to the auxiliary generator may be used only under some conditions, for example, when the state of charge is less than a second, low threshold or when a vehicle in which the engine is positioned slows down , In this way, the charging of the battery between the primary generator and the auxiliary generator is coordinated so that the charging of the battery via the primary generator is reduced. Thus, fuel consumption due to use of the primary generator can be reduced.

It should be understood that the summary above is intended to introduce in simplified form a selection of concepts that are further described in the detailed description. It is not intended to disclose key or essential features of the claimed subject matter whose scope is defined solely 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 other part of this disclosure.

Brief description of the drawings

1 shows a schematic diagram of an engine.

2 shows a schematic diagram of a throttle-valve turbine generator in an engine system.

3 FIG. 12 is a flowchart illustrating a routine for controlling a valve position of a throttle bypass valve in a throttle-valve generator. FIG.

4 FIG. 10 is a flowchart illustrating a routine for controlling the charging of a battery in an engine system with a throttle-valve generator. FIG.

5 FIG. 10 is a flowchart illustrating a routine for controlling airflow to an engine during a transient operating condition. FIG.

6 shows a block diagram of an engine airflow calculation model.

7 shows graphs showing the throttle position and air flow through the throttle during a transient operating condition.

8th shows graphs showing the throttle position and air flow through the throttle during a transient operating condition.

Detailed description

The following description relates to systems and methods for an engine having a Throttle turbine generator. In one example embodiment, when a state of charge of a battery is below a threshold, a method includes directing intake air through a throttle bypass around a throttle disposed in an intake passage of the engine and through a turbine to drive an auxiliary generator. Furthermore, the method includes charging the battery via the additional generator. In such an example, the threshold may be a first, high threshold corresponding to a maximum state of charge of the battery. Thus, the boost generator supplies power to charge the battery whenever charging is required while intake air flows through the throttle bypass. However, under some conditions, such as under idle conditions, where airflow through the throttle bypass may be disrupted, a mechanically driven primary generator may be used to charge the battery when the state of charge is below a second, low threshold. In this way, charging of the battery by the primary generator can be performed only under some conditions, so that the fuel economy of the engine system is improved.

In some embodiments, an exemplary engine system includes a throttle bypass around a throttle located in an intake system of the engine system. Furthermore, the throttle bypass includes a turbine that communicates with an auxiliary generator. An exemplary method includes adjusting an operating parameter based on airflow to cylinders of an engine during a transient operating condition. In such an approach, airflow to cylinders of the engine is measured so that airflow to the cylinders in the transient operating condition is known. Thus, one or more engine operating parameters may be adjusted to compensate for the slowed or retarded airflow. For example, operating parameters such as fuel injection timing, fuel injection amount, and / or throttle position may be adjusted if a delay in airflow during the transient operating condition is expected. In one particular example, the throttle position may be adjusted to open the throttle to permit greater airflow through the throttle under a transient tip-in condition. Thus, an air-fuel ratio and torque can be maintained, so that engine operating efficiency, exhaust emissions, and performance during the transient operating state are maintained or improved. In another example, the fuel injection timing may be retarded and / or the fuel injection amount may be adjusted to maintain the air-fuel ratio. In this way, engine operating efficiency and exhaust emissions during transient operating conditions may be maintained or improved. In another example, the throttle opening may be adjusted to maintain the desired airflow to the engine during transient conditions. In this way, the engine operating behavior during transient operating conditions can be maintained or improved.

In another exemplary embodiment, a method based on airflow to the engine includes adjusting a throttle bypass valve to direct at least a portion of the airflow through a throttle bypass around a throttle disposed in an intake passage of the engine and to a turbine coupled to an auxiliary generator. The throttle bypass valve may be, for example, an on / off valve or a flow modulating valve. By adjusting the throttle bypass valve, flow through the throttle bypass can be controlled as desired. For example, if airflow to the engine is below a first threshold, the bypass valve may be adjusted to reduce flow through the throttle bypass so that airflow to the engine is maintained at the desired altitude. Under some conditions, as power generated by the auxiliary generator is increased, power generation by a primary generator can be reduced, thereby improving the fuel economy of the engine system. As another example, if airflow to the engine is relatively low, the bypass valve may be adjusted to reduce airflow through the bypass, but in some cases not be completely reduced. As another example, if airflow to the engine is relatively high, the bypass valve may be adjusted to increase airflow through the bypass. Thus, under conditions where airflow through the throttle bypass is sufficient to allow the turbine to drive the auxiliary generator to charge a battery of the engine, the flow of air through the throttle bypass may be controlled to provide the engine with desired airflow and improve fuel economy ,

1 is a schematic diagram showing a cylinder of a multi-cylinder engine 10 shows, which may be included in a drive system of a motor vehicle. The motor 10 can be at least partially controlled by a control system that has a controller 12 contains, and by input from a driver 132 via an input device 130 to be controlled. In this example, the input device contains 130 an accelerator pedal and a pedal position sensor 134 for generating a proportional pedal position signal PP. The combustion chamber (that is the Cylinder) 30 of the motor 10 can be combustion chamber walls 32 with piston positioned in it 36 contain. The piston 36 can with the crankshaft 40 be coupled, so that the reciprocating motion of the piston is converted into a rotational movement of the crankshaft. The crankshaft 40 can be coupled via an intermediate gear system with at least one drive wheel of a vehicle. Furthermore, a starter motor via a flywheel with the crankshaft 40 be coupled to a startup operation of the engine 10 to enable.

The combustion chamber 30 may intake air from the intake manifold 44 over the inlet channel 42 receive and can combustion gases through the exhaust duct 48 Drain. The intake manifold 44 and the outlet channel 48 can via a respective inlet valve 52 or exhaust valve 54 specifically with the combustion chamber 30 get in contact. In some embodiments, the combustion chamber 30 have two or more intake valves and / or two or more exhaust valves.

In this example, the inlet valve 52 and the exhaust valve 54 by cam actuation via respective cam actuation systems 51 and 53 to be controlled. The cam actuation systems 51 and 53 may each include one or more cams and systems for cam profile switching (CPS) and / or variable cam timing (VCT) and / or variable valve timing (VVS) and / or variable valve lift (VVL) ) use by the controller 12 can be operated to change the valve operation. The position of the inlet valve 52 and the exhaust valve 54 can through position sensors 55 respectively. 57 be determined. In alternative embodiments, the inlet valve 52 and / or the exhaust valve 54 be controlled by electric valve actuation. For example, the cylinder 30 alternatively, an intake valve controlled by electric valve actuation and an exhaust valve controlled via cam actuation, including CPS and / or VCT.

In the illustration is a fuel injector 66 directly with the combustion chamber 30 coupled to fuel proportional to the pulse width of the controller 12 via the electronic driver 68 Inject injected signal FPW therein. In this way, the fuel injector 66 a so-called direct injection of fuel into the combustion chamber 30 ready. The fuel injection valve may be mounted, for example, in the side of the combustion chamber or in the upper part of the combustion chamber. Fuel may be the fuel injector 66 supplied by a not-shown fuel system including a fuel tank, a fuel pump, and a fuel rail. In some embodiments, the combustion chamber 30 alternatively or additionally, in a configuration involving a so-called port injection of fuel into the intake passage upstream of the combustion chamber 30 one in the intake manifold 44 arranged fuel injection valve included.

The inlet channel 42 can a throttle 62 with a throttle plate 64 contain. In this particular example, the position of the throttle plate 64 through the controller 12 can be varied via a signal that is an electric motor or an actuator connected to the throttle 62 is included, this configuration commonly referred to as electronic throttle control (ETC). That way the throttle can work 62 be pressed to that of the combustion chamber 30 to vary intake air supplied under other engine cylinders. The position of the throttle plate 64 can the controller 12 be supplied by a throttle position signal TP. The inlet channel 42 can be an air mass sensor 120 and / or an intake manifold absolute pressure sensor 122 included to the controller 12 to supply respective signals MAF and MAP.

Furthermore, a throttle valve turbine generator 202 with the inlet channel 42 in a bypass around the throttle 62 coupled around. The butterfly valve generator 202 , referring to 2 is described in more detail includes a turbine that drives an additional generator. The booster generator may charge a battery of the engine in addition to being charged by a mechanically driven primary generator and / or as a main charging source, for example when the primary generator is degraded or failed.

The ignition system 88 can the combustion chamber 30 over a spark plug 92 in response to an ignition advance signal SA from the controller 12 provide a spark under selected operating modes. Although spark ignition components are shown, in some examples, the combustor 30 or one or more other combustion chambers of the engine 10 be operated in a self-ignition mode with or without sparks.

The illustration shows an exhaust gas sensor 126 upstream of the emission control device 70 with the outlet channel 48 connected. The sensor 126 Any suitable sensor for providing an indication of exhaust gas air / fuel ratio, such as a linear oxygen sensor or universal or wide-range exhaust gas oxygen (UEGO), a two-state oxygen sensor or an EGO, a HEGO ( heated EGO), a NOx, a HC or a CO sensor. The emission control device 70 is in the illustration along the outlet channel 48 downstream of the exhaust gas sensor 126 arranged. The device 70 may be a three-way catalyst (TWC), NOx trap, various other emission control devices, or combinations thereof. In some examples, the emission control device may 70 during operation of the engine 10 be reset by operating at least one cylinder of the engine in a certain air / fuel ratio regularly.

In the in 1 The illustration shown is the control 12 a microcomputer, which is a microprocessor unit 102 , Input / output ports (I / O) 104 , a read only memory (ROM) chip in this particular example 106 shown electronic storage medium for executable programs and calibration values, a random access memory (RAM) 108 , a conservation memory (KAM) 110 and a data bus. The control 12 In addition to the previously discussed signals different signals from the engine 10 Received coupled sensors, including measurement of the incoming air mass (MAF) from the air mass sensor 120 ; the engine coolant temperature (ECT) of that with the cooling sleeve 114 coupled temperature sensor 112 ; a spark ignition pickup signal (PIP) from that with the crankshaft 40 coupled Hall sensor 118 (or other type of sensor); the throttle position (TP) from a throttle position sensor; and an absolute manifold pressure signal, MAP, from the sensor 122 , The engine speed signal RPM can be controlled by the controller 12 be generated from the signal PIP. Intake manifold pressure signal MAP from a manifold pressure sensor may be used to provide an indication of vacuum or pressure in the intake manifold. It should be noted that various combinations of the above sensors may be used, such as a MAF sensor without a MAP sensor or vice versa. For stoichiometric operation, the MAP sensor may provide an indication of engine torque. Further, this sensor, along with sensed engine speed and other signals, may provide an estimate of the charge (including air) injected into the cylinder. In one example, the sensor 118 , which may also be used as an engine speed sensor, generate a predetermined number of equally spaced pulses each revolution of the crankshaft.

The read-only memory medium 106 may be programmed with computer readable data representing instructions issued by the processor (CPU) 102 for carrying out the methods described below as well as variations thereof which are expected but not specifically mentioned.

As described above, shows 1 only one cylinder of a multi-cylinder engine, and that each cylinder may also include its own set of intake / exhaust valves, a fuel injector, a spark plug, and so on.

Further on 2 Referring to, the throttle-valve generator becomes 202 in an engine system 200 shown the above with reference to 1 described engine 10 contains. The butterfly valve generator 202 contains the turbine 206 and the throttle bypass valve 208 that in the throttle bypass 204 are arranged, and the additional generator 210 from the turbine 206 is driven. In some embodiments, the throttle-valve generator may not include the throttle bypass valve 208 , Instead, for example, the throttle may include a wedge-shaped flap which, under some conditions, blocks airflow to the throttle bypass.

The butterfly valve generator 202 uses energy that is usually wasted by throttling engine intake air. For example, the change in pressure at the throttle 62 for directing air flow through the turbine 206 be used. The turbine 206 drives the additional generator 210 on, the battery 212 Supplying power. With such a configuration, the efficiency of the engine system can be improved because, for example, under some operating conditions, the charging of the battery 212 via a mechanically driven primary generator 214 can be reduced and charging via the auxiliary generator 210 can be increased.

As shown, intake air flows through the intake passage 42 and through the throttle 62 , As described above, a throttle position can be adjusted by the controller 12 are changed, so that an intake air amount supplied to cylinders of the engine is changed. The throttle bypass 204 directs intake air from a position upstream of the throttle 62 and the throttle 62 to a position downstream of the throttle 62 , Intake air may be due to, for example, a pressure differential across the throttle by the throttle bypass 204 be directed. Furthermore, the throttle valve generator includes 202 at the in 2 shown exemplary embodiment, the throttle bypass valve 208 , The throttle bypass valve 208 can be modulated to control the flow of intake air through the throttle bypass 204 to change as with reference to below 3 described. In some examples, the Throttle bypass valve 208 to act on an on / off valve, which is the throttle bypass 204 opens and closes. In other examples, the throttle bypass valve may be 208 to act a Strömungsmodulierventil that a variable amount of air flow through the throttle bypass 204 controls. The throttle bypass valve 208 may be a piston or gate valve, a gate valve, a flap valve, or any other suitable flow control device. Furthermore, the throttle bypass valve 208 by a solenoid, a pulse width modulated solenoid, a DC motor, a stepping motor, a negative pressure diaphragm, or the like.

Through the throttle bypass 204 directed air flow flows through the turbine 206 that the auxiliary generator 210 With the air flow removed energy turns. The additional generator 210 generates electricity, that of the battery 212 is supplied. The battery 212 can be different components of an electrical system of the vehicle in which the engine system 200 are arranged, such as lamps, pumps, blower, fuel injection, ignition, air conditioning and the like, to power. The battery 212 can continue through the primary generator 214 be charged by the engine 10 is mechanically driven. As below with reference to 4 described, charging the battery 212 between the primary generator 214 and the additional generator 210 be coordinated so that the overall efficiency of the system is increased. For example, the auxiliary generator 210 the battery 212 Supply power under conditions that include supplying power to the battery 212 through the primary generator 214 increase fuel consumption, such as during cruise or vehicle acceleration. Furthermore, the additional generator 210 the battery 212 Supply power when the primary generator 214 impaired or failed. The additional generator 210 For example, it may be a less powerful generator that generates less power than the primary generator 214 ,

The 3 - 5 10 are flowcharts illustrating routines for operating an engine system including a throttle-valve generator, such as that described above with reference to FIG 2 described butterfly valve generator 202 , represent. The flowchart in 3 FIG. 12 shows a throttle bypass valve adjustment control routine for controlling the flow of air through the throttle bypass and therefore through the turbine based on the flow of air to the engine. The flowchart in 4 shows a control routine for charging the battery via the throttle valve generator (eg the auxiliary generator) and the primary generator. The flowchart in 5 FIG. 12 shows a control routine for adjusting the air flow to the cylinders during a transient engine operating condition when, for example, a throttle position changes rapidly and / or a rotational speed of the turbine changes. Each routine may be performed at different times or concurrently by the same controller. For example, the throttle bypass valve may be controlled to adjust the air flow through the throttle bypass while controlling the charging of the battery via the auxiliary generator and / or the primary generator. As another example, during a transient condition, the throttle bypass valve may be adjusted based on the change in airflow through the throttle.

3 shows a flowchart illustrating a control routine 300 for adjusting a throttle bypass valve for controlling the flow of air through a throttle bypass, such as that described above with reference to FIG 2 described throttle bypass valve 208 , represents. In particular, the routine determines 300 the airflow to the engine and adjusts the throttle bypass position based on the airflow. In some examples, the controller may use proportional-integral-derivative (PID) controllers. In other examples, the controller may use an open loop or open loop component plus feedback. For example, the feedback may be airflow and the airflow may be the measured actual airflow to cylinders of the engine and / or based on intake manifold pressure and / or engine speed.

at 302 the routine 300 the operating conditions are determined. The operating conditions may include engine speed, engine load, intake air temperature and / or pressure (MAP), and / or air flow rate (MAF), and the like.

After determining the operating conditions, the routine goes 300 to 304 via where it is determined whether the air flow is below a threshold air flow (threshold value of an air flow, eg air mass flow measured with air mass sensor 120 ) lies. The airflow used for this determination may be the measured actual airflow or the current airflow derived from other parameters such as engine speed and MAP, or the current desired airflow based on other parameters such as the desired torque. Or the airflow used for this determination may be a measured or derived parameter or airflow predicted by setpoint parameters that will occur soon. The threshold airflow used for this determination may be a minimum airflow required, for example, for the turbine to drive the auxiliary generator. In some examples the threshold airflow can be a constant value. In other examples, the threshold airflow may vary based on one or more operating parameters, such as engine speed, engine load, intake air temperature and / or pressure, and engine temperature.

If it is determined that the first threshold airflow is below the threshold airflow, the routine proceeds 300 to 308 over and the throttle bypass valve is closed. In some examples, the throttle bypass valve may be an on / off valve, and the throttle bypass valve is closed by setting the throttle bypass valve to the off position. In other examples, the throttle bypass valve may be a flow modulating valve. In such an example, the throttle bypass valve is set to a fully closed position to close the throttle bypass valve. For example, in an operating condition, such as in an engine idling condition, the throttle bypass valve may be adjusted to a fully closed position.

On the other hand, if it is determined that the airflow is greater than the first threshold airflow, the routine will proceed 300 to 306 where the extent of throttle bypass valve opening and throttle position are adjusted to maintain airflow to the cylinders of the engine to meet torque requirements. For example, as the torque request increases, the throttle position may be adjusted, for example, so that the throttle is further opened and airflow through the throttle increases. Likewise, the throttle bypass valve may be adjusted so that the throttle bypass opening increases with increasing torque demand. However, in some examples, the throttle bypass opening may be decreased as the throttle position increases. For example, the throttle bypass opening may be reduced or closed when a state of charge of the battery being charged by the throttle turbine generator approaches a threshold and charging by the throttle turbine generator is no longer desired. As another example, the throttle bypass opening may be closed as the throttle position approaches a wide open throttle.

In this way, the throttle bypass valve may be controlled to maintain a desired air flow to the engine. For example, if the airflow is less than the threshold airflow, the valve port is closed so that no airflow flows through the throttle bypass. When the airflow is greater than the threshold airflow, the valve opening and throttle position are adjusted so that airflow to the cylinders of the engine is such that the torque requirements are met while charging the battery, if desired.

4 shows a flowchart illustrating a control routine 400 for charging a battery in an engine system such as that described above with reference to FIG 2 described battery 212 , represents. In particular, routine determines 400 a state of charge of the battery. Based on the state of charge of the battery and other operating conditions (eg, vehicle slowdown, primary generator degradation, etc.), charging of the battery is accomplished via a throttle turbine generator and / or a mechanically driven primary generator.

at 402 the routine 400 determines whether the state of charge (SOC) of the battery is higher than a first threshold value. The first threshold may be a high threshold corresponding, for example, to a state of charge in which the battery is full or maximum charged. If it is determined that the state of charge of the battery is higher than the first threshold, then the routine proceeds 400 to 412 over and the battery is not charged with the primary generator or the choke turbine generator.

On the other hand, if it is determined that the state of charge of the battery is less than the first threshold, then the routine proceeds 400 to 404 and it is determined whether the state of charge of the battery is less than a second threshold. The second threshold may be a low threshold corresponding, for example, to a minimum charge level of the battery below which the battery can not provide enough power to operate various components of the vehicle's electrical system. As another example, the second threshold may correspond to a charge level that may provide energy for a particular duration. Thus, the second threshold is less than the first threshold.

If it is determined that the state of charge of the battery is higher than the second threshold, the routine proceeds 400 to 406 about where it is determined if the vehicle is slowing down. A deceleration of the vehicle may be determined when a speed of the vehicle decreases when an operator of the vehicle is not exerting pressure on an accelerator pedal when an operator of the vehicle applies pressure to brakes of the vehicle and / or in any other suitable manner.

If it is determined that the vehicle is slowing down, the routine goes 400 to 408 where the battery is being charged with the primary generator and the throttle-valve generator (eg, the auxiliary generator). During deceleration of the vehicle, the primary generator can generate power for charging the battery, for example via regenerative braking, without increasing fuel consumption. Furthermore, the auxiliary generator can also provide power for charging the battery. In this way charging of the battery can be maximized when the vehicle slows down.

On the other hand, if it is determined that the vehicle is not slowing down, the routine goes 400 to 410 over and the battery is charged with the choke turbine generator. For example, since the state of charge of the battery is higher than the second threshold, and since charging the battery via the primary generator under non-deceleration conditions may increase fuel consumption, the battery may be charged only via the auxiliary generator driven by the turbine of the butterfly-type turbine generator.

If, too 404 Returning, it is determined that the state of charge of the battery is less than the second threshold, the routine goes 400 to 414 where it is determined if the primary generator is affected. A generator degradation may be determined, for example, based on a decreasing amount of current generated by the generator or generated voltage, a lack of power or voltage for the battery, or the like.

If it is determined that the primary generator is degraded, the routine proceeds 400 to 420 Over and under pressure in the intake manifold is maximized so that charging the battery via the turbine is reduced. For example, by increasing the negative pressure in the intake manifold, the pressure differential across the throttle is increased, thereby increasing intake airflow to the throttle bypass and increasing energy available to the turbine. The intake manifold vacuum may be increased, for example, by adjusting the air-fuel ratio and / or the exhaust gas recirculation (EGR) and / or the variable valve timing and / or the gear ratio and / or deactivating the cylinder deactivation and / or turning on a mechanically driven negative pressure pump. In one example, the gear ratio may be adjusted by downshifting to increase the negative pressure in the intake manifold. As another example, an EGR amount may be reduced to increase negative pressure in the intake manifold. In another example, the air-fuel ratio may be reduced (eg, stoichiometric operation rather than lean) to increase negative pressure in the intake manifold.

In some examples, such actions may be performed to increase intake manifold vacuum, thereby increasing charging by the auxiliary generator, even if the primary generator is not compromised. In general, however, such actions may increase fuel economy, thereby reducing fuel economy. In some examples, the controller may calculate the fuel economy disadvantage of increasing the intake manifold vacuum versus operation of the primary generator and choose the more efficient way of increasing the electrical power to the battery.

On the other hand, if it is determined that the primary generator is not affected, the routine goes 400 to 416 about where it is determined if the vehicle is slowing down. As described above, slowing down of the vehicle may be determined when a speed of the vehicle decreases when an operator of the vehicle is not pressing an accelerator pedal when an operator of the vehicle applies pressure to brakes of the vehicle and / or in any other suitable manner , as described above.

If it is determined that the vehicle is slowing down, the routine goes 400 to 408 over and the battery is charged via the choke turbine generator and the primary generator as described above. The charging of the battery can be maximized, for example, as it is charged via both the auxiliary generator and the primary generator, while reducing an effect on fuel economy due to charging with the primary generator.

On the other hand, if it is determined that the vehicle is not slowing down, the routine goes 400 to 418 over and the battery is charged as much as the intake manifold vacuum allows via the choke turbine generator and the battery is charged with the primary generator only enough to meet the target total battery charge. For example, because the fuel economy may be reduced by increasing the intake manifold vacuum, the battery may only be charged as much as the current intake manifold negative pressure via the boost generator. Because the primary generator can reduce fuel economy, the primary generator can be operated analogously to generate only enough power for the battery to meet the total charge of the battery. Thus, in some examples, more power may be supplied to the battery from the boost generator than from the primary generator (eg, when the pressure drop across the throttle is relatively high). In other examples, more power may be supplied to the battery from the primary generator than from the auxiliary generator (eg, when the pressure drop across the throttle is relatively low).

In this way, the charging of the battery between the primary generator and the auxiliary generator can be coordinated to increase the overall efficiency of the system. For example, upon deceleration, when a fuel economy disadvantage is small, power may be supplied to the battery from both the auxiliary generator and the primary generator, thereby maximizing the charging of the battery. Under conditions where a fuel economy disadvantage is high, power can be supplied to the battery only from the booster, so that fuel consumption is reduced.

Further on 5 Turning to, a routine becomes 500 to control the flow of air to the engine during transient conditions. In particular, the routine determines 500 whether a transient condition is occurring, and adjusts the airflow to the cylinders of the engine (eg, load) accordingly, while taking rotational inertia of the turbine into account. For example, the turbine may have high rotational inertia, and turbine speed may vary from zero RPM at idle and relatively high loads when the throttle bypass valve is closed to over 70,000 RPM at low to medium loads. Thus, transient changes in throttle position may not cause immediate corresponding changes in airflow.

at 502 the routine 500 the operating conditions are determined. The operating conditions may include engine speed, engine load, intake air flow rate and / or pressure, throttle position, accelerator pedal position, ambient pressure, ambient temperature, and the like.

After determining the operating conditions, the routine goes 500 to 504 about where it is determined whether a transient state occurs. For example, a transient condition may be identified based on a change in transmission ratio, a relatively rapid change in throttle or pedal position, a change in turbine speed, and / or changes in intake manifold pressure or airflow.

If it is determined that there is no transient condition (for example, the engine is in a non-stationary state), the routine proceeds 500 to 506 where airflow to the engine is determined using a first load calculation based on measurements from an air mass sensor. For example, since no transient condition occurs, the measured airflow directly corresponds to the airflow to the cylinders. Thus, the first load calculation may be on one of an air mass sensor positioned in an intake passage of the engine, such as the air mass sensor described above with reference to FIG 120 , measured air mass.

On the other hand, if it is determined that a transient condition is occurring, the routine proceeds 500 to 508 where airflow to the engine is determined using a second load calculation, and an operating parameter is set based on the airflow to the cylinders of the engine. The air flow into the cylinders (eg, load) may be calculated, for example, via the second load calculation, since the first load calculation may be inaccurate due to the delay caused by the rotational inertia of the turbine.

As an example, at 510 Speed density calculated from the manifold air pressure instead of the air mass used to calculate the load. As another example, in 512 the load is based on a time constant of the turbine. For example, the time constant may be a function of a parameter such as air flow through the throttle, change in pressure at the throttle, turbine speed, and / or current generated by the auxiliary generator. In one example, the airflow to the engine is based on an airflow model, such as that in FIG 6 shown engine airflow calculation model 600 , certainly. In such an example, the airflow measured by the air mass sensor becomes 602 meted out. For example, it is determined what percentage of the airflow is directed through the throttle bypass and what percentage of the airflow is through the throttle. For example, the percentage of airflow passing through the throttle bypass may vary based on the opening of the throttle bypass valve and the throttle position. Similarly, the percentage of airflow passing through the throttle may vary based on the opening of the throttle bypass valve and the throttle position.

As described above, due to the rotational inertia of the turbine during unsteady conditions, the airflow leaving the turbine is different from the airflow entering the throttle bypass. Thus, the percentage of airflow passing through the throttle bypass and therefore the turbine is dictated by the turbine model 604 set. The turbine model 604 may apply one or more filters to the airflow percentage, including one Time constants of the turbine include. For example, the turbine model 604 an inertial model that quantifies turbine airflow delay during transient conditions. In this way, flow through the throttle bypass and the turbine and into the intake manifold can be determined.

After application of the turbine model 604 The set airflow and the percentage of airflow passing through the throttle valve will contribute 606 summed to determine the flow of air through the intake manifold downstream of the throttle. Then the manifold filling model becomes 608 applied to the airflow to determine the flow of air into the cylinders of the engine (for example, load). The manifold filling model 608 may depend on such parameters as intake manifold size and volume, engine speed and variable valve timing and the like.

Further on 5 Referring to the calculation of airflow into the cylinders, one or more operating parameters, such as fuel injection timing and / or fuel injection amount, may be adjusted according to the actual airflow. For example, one or more operating parameters may be adjusted in response to an airflow change due to the delay of up or down the turbine. In one example, the fuel injection amount is reduced in response to a reduction in the airflow. The reduction in airflow may be due to an increase in throttle opening and a delayed change in airflow due to rotational inertia of the turbine during the transient condition. As another example, the fuel injection timing is retarded in response to a decrease in airflow to the cylinders of the engine. For example, in this way during the transient operating state, the accuracy of the air-fuel ratio control can be enhanced and exhaust emissions can be reduced.

In some examples, an operating parameter may be included 514 based on steady state mapping of airflow versus throttle position and changing the pressure on the throttle. For example, the throttle position may be adjusted to be moved further and / or faster to increase airflow through the throttle during transient operating conditions in response to a reduction in airflow through the throttle bypass due to rotational inertia of the turbine. For example, the modified throttle position may be based on a calculation of the throttle position required to deliver the desired airflow during the transient state (eg, the transient airflow), taking into account the time constant of the turbine. In this way, the accuracy of the output of the target torque can be increased, whereby the driveability, for example, during the transient operating state, is improved.

In some examples, the throttle bypass valve may be closed when a large increase in transient airflow is requested, such as during a tip-in. In this way, the full intake air flow is available to the cylinders of the engine without delay due to the rotational inertia of the turbocharger.

Thus, during transient engine operating conditions, one or more operating parameters may be adjusted to improve engine operating efficiency and / or exhaust emissions and / or driveability.

7 FIG. 12 is a graph illustrating the airflow delay due to rotational inertia of the turbine during a transient operating condition. FIG. The solid line 702 shows the throttle position as a function of time. As shown, the throttle position begins in a first position and opens between the time t ₁ and the time t ₂ in a second position. The solid line 704 shows the ideal airflow through the throttle to the intake manifold. The ideal airflow corresponds to the throttle opening so that as the throttle position opens (or closes), airflow to the intake manifold increases (or decreases) by an amount corresponding to the change in throttle opening. The dashed line 706 shows the actual air flow through the throttle and the throttle bypass to the intake manifold. As shown, there is a delay in the increase in airflow between the increase in throttle opening and the increase in airflow. For example, the ideal airflow is achieved only some time after time t ₂ . This is due, for example, to the rotational inertia of the turbine as the turbine speed changes.

8th FIG. 12 shows diagrams showing a modified throttle control system, with reference to FIG 5 is described. The solid line 802 shows the standard throttle position as a function of time (for example, the in 7 by line 702 shown throttle position) during a transient engine operating condition. Like that in 7 example shown, the throttle position begins with a first position and opens between the time t ₁ and the time t ₂ in a second position. The dashed line 804 shows the modified throttle position. As shown, according to the modified throttle control, the throttle valve is opened to a greater extent than the standard throttle valve, starting at time t ₁ and ending at time t ₃ .

The solid line 806 shows the flow of air through the throttle, the one through the line 802 in a system that does not include a throttle-valve generator, throttle position shown. The white-dotted line 808 FIG. 12 shows the flow of air through the throttle during a transient condition in a system including a throttle-valve generator, such as that described above with reference to FIG 1 described engine system. As shown, the air flow through the throttle reaches the airflow corresponding to the second throttle position at time t ₃ , which is later than the time t ₂ due to the reduced air flow through the throttle. The black-dotted line 810 shows the flow of air through the throttle when the throttle position according to a modified throttle control, the throttle position line 804 corresponds, is set. As shown, the flow of air through the throttle by adjusting the throttle position in a system including a throttle turbine generator is substantially equal to the flow of air through the throttle in a system that does not include a throttle turbine generator during a transient condition.

Thus, a routine such as that described above with reference to 5 described routine 500 in which the throttle control is modified to adjust the throttle position during transient operating conditions. In this way, airflow through the throttle may remain substantially the same, and a desired torque may be maintained during the transient condition.

In one embodiment, a method for an engine comprises: when a state of charge of a battery is below a threshold, directing intake air through a throttle bypass around a throttle located in an intake passage of the engine and through a turbine to drive an auxiliary generator; and charging the battery via the auxiliary generator.

In another embodiment, the method further comprises slowing down a vehicle in which the engine is positioned, charging the battery via the auxiliary generator, and a primary generator.

In another embodiment, the threshold is a first, high threshold, and further comprising charging the battery via the auxiliary generator when the state of charge is below a second, low threshold.

In another embodiment, the threshold is a first, high threshold, and further comprising, upon deceleration of a vehicle in which the engine is positioned, charging the battery via the auxiliary generator and a primary generator when the state of charge is below a second, low threshold.

In another embodiment, the threshold is a first, high threshold, and further comprising charging the battery via the auxiliary generator and a primary generator when the state of charge is below a second, low threshold and the vehicle is not slowing down.

In another embodiment, the threshold is a first, high threshold, and further comprising charging the battery via the auxiliary generator when the state of charge is below a second, low threshold and a primary generator is compromised. Further, the method includes adjusting the variable valve timing and / or exhaust gas recirculation and / or gear ratio and / or the cylinder deactivation and / or the vacuum pump and / or the air-fuel ratio to increase the charge via the auxiliary generator when the primary generator is impaired ,

In one embodiment, a method for an engine includes: under a first condition, directing intake air through a throttle bypass around a throttle disposed in an intake passage of the engine and through a turbine for driving an auxiliary generator to maintain a state of charge of a battery; and, under a second condition, adjusting an engine operating parameter to increase the charge of the battery via the auxiliary generator.

In another embodiment, the second condition includes that the state of charge of the battery is less than a threshold and a primary generator is compromised. Further, the method comprises increasing the negative pressure in an intake manifold of the engine downstream of the throttle to increase the charge of the battery via the turbine by adjusting the variable valve timing and / or exhaust gas recirculation and / or gear ratio, wherein the gear ratio is adjusted by downshifting Low pressure in the intake manifold too increase. Furthermore, the method includes reducing an amount of exhaust gas recirculation to increase the negative pressure in the intake manifold. Further, the method includes reducing the air-fuel ratio to increase the negative pressure in the intake manifold.

In another embodiment, the first condition includes slowing down a vehicle in which the engine is positioned, and further comprising, under the first condition, charging the battery via the auxiliary generator and a primary generator.

In one embodiment, a system for an engine includes: a throttle located in an intake passage in the engine; a throttle bypass configured to direct intake air from a position upstream of the throttle to a position downstream of the throttle; a turbine disposed in the throttle bypass, wherein the turbine is configured to drive an auxiliary generator in electrical communication with a battery, the battery further being in electrical communication with a primary generator; and a controller configured to identify a state of charge of the battery and to charge the battery with the primary generator and / or the auxiliary generator based on the state of charge of the battery and an operating condition.

In another embodiment, the controller is further configured to determine whether a vehicle in which the engine is positioned is slowing down.

In another embodiment, the controller is further configured to charge the battery with the primary generator and the auxiliary generator when the state of charge is below a first, high threshold and the vehicle is slowing down.

In another embodiment, the controller is further configured to charge the battery with the auxiliary generator when the state of charge is below a first, high threshold and is greater than a second, lower threshold and the vehicle is not slowing down.

In another embodiment, the controller is further configured to identify a degradation of the primary generator and, in response to the identification of a degradation of the primary generator, to charge the battery with the auxiliary generator when the state of charge is below a first, high threshold.

In another embodiment, the controller is configured to adjust the variable cam timing and / or the exhaust gas recirculation and / or the gear ratio and / or the cylinder deactivation and / or the vacuum pump and / or the air-fuel ratio to charge by the auxiliary generator increase.

In one embodiment, a method includes: in an engine system including a throttle bypass around a throttle located in an intake passage of the engine system, the throttle bypass including a turbine in communication with an auxiliary generator, setting an operating parameter based on airflow to cylinders a motor during a transient operating state. Furthermore, the method includes determining the airflow based on the engine speed density during the transient operating condition.

In another embodiment, the operating parameter is fuel injection timing and / or fuel injection amount. Further, the method includes adjusting the fuel injection amount during the transient operating condition in response to a change in the airflow due to a delay in a spin up or down of the turbine.

In another embodiment, the method further comprises determining the airflow based on a time constant of the turbine. Further, the time constant is a function of the air flow through the throttle, the pressure drop across the throttle, the speed of the auxiliary generator, or a current or voltage generated by the auxiliary generator. Furthermore, the method includes charging a battery of the engine system via the auxiliary generator.

In another embodiment, the operating parameter is a throttle position, and the method further comprises adjusting the throttle position to change a throttle opening during the transient operating state in response to a change in the air flow due to a retardation during spin up or down of the turbine.

In another embodiment, the method further comprises determining during a transient operating condition Air flow to the engine based on the air mass upstream of a throttle valve.

In another embodiment, the method includes: during a non-stationary operating condition, determining an airflow to the engine based on the air mass upstream of a throttle; and, during a transient operating condition, determining the air flow to the engine based on the velocity density or a time constant of a throttle bypass turbine directing intake air around the throttle and setting an operating parameter based on the air flow to the engine.

In another embodiment, the time constant is a function of the flow of air through the throttle, the pressure drop across the throttle, the speed of the boost generator, or a current or voltage generated by a turbine-driven boost generator.

In another embodiment, the operating parameter is fuel injection timing and / or fuel injection amount and / or throttle position. Further, the method includes adjusting the throttle position to adjust throttle opening in response to a change in airflow to the engine during the transient operating condition due to a delay in spin-up or spin-down of the turbine. Further, the method includes adjusting the amount of fuel injection in response to a change in airflow to the engine during the transient operating condition due to a retardation of spin-up or spin-down of the turbine.

In one embodiment, a system for an engine includes: a throttle located in an intake passage in the engine; a throttle bypass containing a turbine coupled to an auxiliary generator; and a controller configured to identify an airflow to the engine and, during a transient operating condition, to adjust one or more operating parameters in response to the airflow to the engine.

In another embodiment, the one or more operating parameters include fuel injection timing, fuel injection amount, and throttle position. In another embodiment, the controller is further configured to retard the fuel injection timing in response to a decrease in airflow to the engine during the transient operating condition.

In another embodiment, the controller is further configured to adjust the throttle position by adjusting an opening of the throttle in response to a change in airflow to the engine during the transient operating state due to a retardation of spin-up or spin-down of the turbine.

In another embodiment, the controller is further configured to identify the airflow to the engine based on the engine speed density during the transient operating condition.

In another embodiment, the controller is further configured to identify the flow of air to the engine based on a time constant of the turbine, wherein the time constant of the turbine is a function of the air flow through the throttle, the pressure drop across the throttle, the speed of the additional generator, or a / is a current or voltage generated by the additional generator.

In one embodiment, a method for an engine based on air flow to the engine includes adjusting a throttle bypass valve to direct at least a portion of the airflow through a throttle bypass around a throttle disposed in an intake passage of the engine and to a turbine coupled to an auxiliary generator.

In another embodiment, the method further includes closing the throttle bypass valve to reduce airflow through the throttle bypass when the airflow is below a threshold airflow. Further, the method includes adjusting the throttle bypass valve to increase the flow of air through the throttle bypass when the airflow is greater than the threshold airflow. Further, the method includes adjusting a throttle position to maintain airflow to the engine to meet torque requirements.

In another embodiment, the method further comprises adjusting the throttle bypass valve to reduce airflow through the throttle bypass based on a measured airflow and / or intake manifold pressure and / or throttle position and / or the desired torque and / or engine speed.

In another embodiment, the method further comprises adjusting the throttle bypass valve to increase the flow of air through the throttle bypass based on the measured airflow and / or the intake manifold pressure and / or the throttle position and / or the desired torque and / or the engine speed. In another embodiment, the method further comprises driving the Additional generator via the turbine to generate electricity for charging a battery of the engine.

In one embodiment, a method for an engine includes: under a first condition, closing an opening of a throttle bypass valve to direct airflow through a throttle to the engine; and, under a second condition, adjusting the throttle bypass valve and a throttle position to direct airflow to the engine and through a throttle bypass to the throttle and to a turbine that drives an auxiliary generator.

In another embodiment, the method further includes closing the throttle bypass valve when the airflow is below a threshold airflow. In another embodiment, the threshold airflow varies with engine speed and / or engine load and / or manifold air temperature and / or engine temperature. In another embodiment, the threshold air flow is a constant value.

In another embodiment, the method further comprises, under the second condition, adjusting the throttle bypass valve based on a state of charge of a battery that is in electrical communication with the auxiliary generator.

In another embodiment, the method further comprises reducing the opening of the throttle bypass valve in response to a reduced measured airflow and / or a reduced intake manifold pressure and / or a reduced throttle position and / or a reduced target torque and / or a reduced engine speed.

In another embodiment, the method further comprises increasing the opening of the throttle bypass valve in response to increased measured airflow and / or increased intake manifold pressure, and / or increased throttle position, and / or increased target torque, and / or engine speed.

In one embodiment, a system for an engine includes: a throttle located in an intake passage in the engine; a throttle bypass with an adjustable throttle bypass valve; and a turbine disposed in the throttle bypass, wherein the turbine is mechanically coupled to an auxiliary generator.

In another embodiment, the system further includes a controller configured to identify an airflow to the engine and to adjust the throttle bypass valve in response to the airflow to control the airflow through the throttle bypass.

In another embodiment, the throttle bypass valve is closed when the airflow to the engine is below a threshold airflow.

In another embodiment, the controller is further configured to adjust the throttle bypass valve and a throttle position when the airflow is above the threshold airflow. In another embodiment, the controller is further configured to close the throttle bypass valve when the throttle position is a wide open throttle.

In another embodiment, the air flow to the engine corresponds to a motor torque.

In another embodiment, the controller is further configured to adjust the throttle bypass valve according to feedback including measured airflow and / or intake manifold pressure and / or engine speed and / or auxiliary generator speed and / or booster output voltage and / or state of charge of a battery connected to the booster generator in FIG electrical connection is set.

It should be appreciated that the example control and estimation routines included herein can be used with various engine and / or vehicle system configurations. The particular routines described herein may represent one or more of a number of processing strategies, such as event-driven, interrupt-driven, multi-tasking, multi-threading, and the like. Thus, various illustrated acts, operations, or functions may be performed in the illustrated order or in parallel, or omitted in some instances. Also, the processing order need not necessarily achieve the features and advantages of the example embodiments described herein, but is provided for ease of illustration and description. One or more of the illustrated acts or functions may be repeatedly performed depending on the particular strategy being used. Furthermore, the actions described may graphically represent a code to be programmed into the computer-readable storage medium in the engine control system. It should be understood that the configurations and routines disclosed herein are merely exemplary and that these particular embodiments are not to be considered in a limiting sense, as numerous variations are possible. For example, the above technology can be applied to V-6, I-4, I-6, V-12, Boxer 4, and other engine types. The subject matter of the present disclosure thus includes all novel and non-obvious combinations and subcombinations of the various systems and configurations and other features, functions, and / or properties disclosed herein.

The following claims specifically point to certain combinations and subcombinations that are considered to be novel and not obvious. These claims may refer to "a" element or "a first" element or the equivalent thereof. Such claims should be understood to embrace the inclusion of one or more such elements, neither requiring nor excluding two or more such elements. Other combinations and sub-combinations of the disclosed features, functions, elements and / or properties may be claimed through amendment of the present claims or through presentation of new claims in this or a related application.

Such claims, whether their scope is further, narrower, equal, or different with respect to the original claims, are also considered to be within the scope of the present disclosure.

Claims (20)

Method for an engine, comprising: when a state of charge of a battery is below a threshold, directing intake air through a throttle bypass around a throttle located in an intake passage of the engine and through a turbine for driving an auxiliary generator; and Charging the battery via the additional generator. The method of claim 1, further comprising slowing down a vehicle in which the engine is positioned, charging the battery via the auxiliary generator, and a primary generator. The method of claim 1, wherein the threshold is a first, high threshold, and further comprising charging the battery via the auxiliary generator when the state of charge is below a second, low threshold. The method of claim 1, wherein the threshold is a first, high threshold, and further comprising, upon deceleration of a vehicle in which the engine is positioned, charging the battery via the auxiliary generator and a primary generator when the state of charge is below a second, low threshold lies. The method of claim 1, wherein the threshold is a first, high threshold, and further comprising charging the battery via the auxiliary generator and a primary generator when the state of charge is below a second, low threshold and the vehicle is not slowing down. The method of claim 1, wherein the threshold is a first, high threshold, and further comprising charging the battery via the auxiliary generator when the state of charge is below a second, low threshold and a primary generator is compromised. The method of claim 6, further comprising adjusting the variable valve timing and / or the exhaust gas recirculation and / or the gear ratio and / or the cylinder deactivation and / or the vacuum pump and / or the air-fuel ratio to increase the charge via the auxiliary generator, if Primary generator is impaired. Method for an engine, comprising: under a first condition, directing intake air through a throttle bypass around a throttle disposed in an intake passage of the engine and through a turbine for driving an auxiliary generator to maintain a state of charge of a battery; and under a second condition, adjusting an engine operating parameter to increase the charge of the battery via the auxiliary generator. The method of claim 8, wherein the second condition includes that the state of charge of the battery is less than a threshold and a primary generator is compromised. The method of claim 9, further comprising increasing the negative pressure in an intake manifold of the engine downstream of the throttle to increase the charge of the battery via the turbine by adjusting the variable valve timing and / or exhaust gas recirculation and / or the gear ratio and / or the cylinder deactivation and / or the vacuum pump and / or the air-fuel ratio. The method of claim 10, further comprising setting the gear ratio by downshifting to increase the negative pressure in the intake manifold. The method of claim 10, further comprising reducing an amount of exhaust gas recirculation to increase the negative pressure in the intake manifold. The method of claim 10, further comprising decreasing the air-fuel ratio to increase the negative pressure in the intake manifold. The method of claim 8, wherein the first condition includes decelerating a vehicle in which the engine is positioned, and further comprising, under the first condition, charging the battery via the auxiliary generator and a primary generator. System for an engine, comprising: a throttle valve disposed in an intake passage in the engine; a throttle bypass configured to direct intake air from a position upstream of the throttle to a position downstream of the throttle; a turbine disposed in the throttle bypass, wherein the turbine is configured to drive an auxiliary generator in electrical communication with a battery, the battery further being in electrical communication with a primary generator; and a controller configured to identify a state of charge of the battery and to charge the battery with the primary generator and / or the auxiliary generator based on the state of charge of the battery and an operating condition. The system of claim 15, wherein the controller is further configured to determine whether a vehicle in which the engine is positioned is slowing down. The system of claim 16, wherein the controller is further configured to charge the battery with the primary generator and the auxiliary generator when the state of charge is below a first, high threshold and the vehicle is slowing down. The system of claim 16, wherein the controller is further configured to charge the battery with the auxiliary generator when the state of charge is below a first, high threshold and is higher than a second, lower threshold and the vehicle is not slowing down. The system of claim 15, wherein the controller is further configured to identify a degradation of the primary generator, and in response to the identification of a degradation of the primary generator, charging the battery with the auxiliary generator when the state of charge is below a first, high threshold. The system of claim 19, wherein the controller is configured to set the variable cam timing and / or the exhaust gas recirculation and / or the gear ratio and / or the cylinder deactivation and / or the vacuum pump and / or the air-fuel ratio to charge by the Increase additional generator.

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