Vehicle control device

Abstract

A vehicle control device capable of avoiding deterioration of NV characteristics of a vehicle and properly starting an internal combustion engine by crank rotation of an electric motor. A control device (30) controls a vehicle provided with an engine (11), a motor generator (12) coupled to the engine, and drive wheels (DW) driven by output of at least one of the engine and the motor generator, and the vehicle (1) is capable of starting the engine (11) by crank rotation driven by the motor generator (12), in the case where the engine (11) is started, before the engine (11) is in a fully combusting state, the control device (30) controls motoring torque of the motor generator (12) based on intake air pressure; after the engine (11) is in the fully combusting state, the control device (30) controls regenerative torque of the motor generator (12) based on fuel injection amount to the engine 11 until the engine speed converges within a prescribed range.

Description

TECHNICAL FIELD

[0001] The present application relates to a vehicle control device. BACKGROUND

[0002] In the past, in a vehicle equipped with an internal combustion engine, it has been desired to reduce vibrations generated at the time of starting the internal combustion engine. For example, in Patent Literature 1, there is disclosed a technology in which, in a hybrid vehicle equipped with an engine and a motor generator and capable of starting the engine by rotation of a crankshaft driven by the motor generator, valve timing control that advances the closing timing of an intake valve of the engine so as to cross a bottom dead center is executed at the time of starting the engine, and at the time of executing the valve timing control, the motor generator is controlled so that the output torque of the motor generator becomes a torque obtained by adding a vibration damping torque determined in accordance with the intake pressure and the closing timing to a crankshaft rotation torque required for rotation of the crankshaft of the engine.

[0003] In addition, in Patent Literature 2, there is disclosed a technology in which a torque pulsation generated in a torque from an internal combustion engine is detected, and a motor generator is controlled to generate a reduction torque in phase with the torque pulsation.

[0004] PRIOR ART DOCUMENTS

[0005] PATENT LITERATURE

[0006] Patent Literature 1: Japanese Patent Application Publication No. 2020-045035

[0007] Patent Literature 2: Japanese Patent Application Publication No. 2004-222439 SUMMARY

[0008] PROBLEMS TO BE SOLVED BY THE INVENTION

[0009] In a vehicle equipped with an internal combustion engine, a motor linked to the internal combustion engine, and drive wheels driven by the output of at least one of the internal combustion engine and the motor, the internal combustion engine is started by rotation of a crankshaft driven by the motor. In this case, in order to shorten the period of generation of vibrations that can cause discomfort to a driver, it is necessary to increase the motoring torque of the motor at the time of starting the internal combustion engine to start the internal combustion engine quickly. On the other hand, if the motoring torque of the motor is maintained even after the internal combustion engine is started, the rotational speed of the internal combustion engine overshoots, which can cause deterioration of the NV (Noise, Vibration) characteristics of the vehicle.

[0010] The present application provides a vehicle control device that can avoid deterioration of the NV characteristics of a vehicle and appropriately start an internal combustion engine by rotation of a crankshaft driven by a motor.

[0011] MEANS FOR SOLVING THE PROBLEMS

[0012] The vehicle control device of the present application controls a vehicle that has:

[0013] an internal combustion engine; an electric motor coupled to the internal combustion engine; and drive wheels driven by an output of at least one of the internal combustion engine and the electric motor, and the vehicle is capable of starting the internal combustion engine by rotation of a crankshaft of the electric motor,

[0014] wherein, in a case where the internal combustion engine is started by rotation of the crankshaft of the electric motor, the vehicle control device performs the following processing:

[0015] controlling a motoring torque of the electric motor based on an intake air pressure of the internal combustion engine before the internal combustion engine is in a full combustion state,

[0016] controlling a regenerative torque of the electric motor based on a fuel injection amount injected to the internal combustion engine after the internal combustion engine is in the full combustion state until a rotational speed of the internal combustion engine converges within a prescribed range including a target rotational speed.

[0017] Effects of the Invention

[0018] The vehicle control device of the present application can avoid deterioration of NV characteristics of a vehicle and appropriately start an internal combustion engine by rotation of a crankshaft of an electric motor. BRIEF DESCRIPTION OF DRAWINGS

[0019] Figure 1 is a view that shows an example of a vehicle of the present embodiment.

[0020] Figure 2 is a view that shows an example of a transmission provided in the vehicle of the present embodiment.

[0021] Figure 3A is a view that shows an example of control performed by the control device in a case where the engine is started in a throttle closed state.

[0022] Figure 3B is a view that shows an example of control performed by the control device in a case where the engine is started in a throttle closed state. Figure 3A is a view that shows an example of control performed by the control device in a case where the engine is started in a throttle closed state.

[0023] Figure 4 is a view that shows an example of control performed by the control device in a case where the engine is started in a throttle closed state.

[0024] Explanation of Reference Numerals

[0025] 1 vehicle

[0026] 11 engine (internal combustion engine)

[0027] 12 motor generator (electric motor)

[0028] 30 control device

[0029] DW drive wheels DETAILED DESCRIPTION

[0030] Hereinafter, one embodiment of a vehicle control device of the present application will be described in detail with reference to the drawings.

[0031]

Vehicle

[0032] As Figure 1 shown, the vehicle 1 of the present embodiment is a so-called hybrid electrical vehicle, and is provided with an engine 11 as an example of an internal combustion engine, a motor generator 12 as an example of an electric motor, a transmission TM, drive wheels DW, a storage battery 20, a power conversion device 21, and a control device 30 that controls the entire vehicle 1. In addition, in the present embodiment, the engine 11 is a so-called cylinder deactivation engine configured to be able to switch between full cylinder operation in which all cylinders are operated and cylinder deactivation operation in which a part of the cylinders is stopped. Figure 1 In the present embodiment, a thick solid line indicates mechanical connection, a double dotted line indicates electrical wiring, and a solid arrow indicates a control signal.

[0033] The engine 11 is, for example, a so-called cylinder deactivation engine configured to be able to switch between full cylinder operation in which all cylinders are operated and cylinder deactivation operation in which a part of the cylinders is stopped. As an example, the engine 11 is a V-type 6-cylinder engine provided with a variable valve timing mechanism (not shown), and is configured to be able to stop three cylinders of one cylinder bank by the variable valve timing mechanism. That is, in the engine 11, 6-cylinder operation using six cylinders of two cylinder banks is performed at the time of full cylinder operation, and 3-cylinder operation using only three cylinders of one cylinder bank is performed at the time of cylinder deactivation operation. In addition, the engine 11 is configured to be able to change, for example, the valve opening period, the opening / closing timing, the lift amount, and the like of each intake valve by the variable valve timing mechanism.

[0034] The engine 11 outputs mechanical energy (power) generated by burning fuel (for example, gasoline) supplied thereto by rotating a crankshaft 11a (refer to Figure 2 ). Specifically, the engine 11 is provided with an injector (not shown). The injector is controlled by the control device 30 using pulse width modulation (PWM) control, and fuel is supplied to the engine 11.

[0035] Specifically, the injector is opened only during a period corresponding to the pulse width of a pulse signal (voltage signal) received as a fuel injection signal from the control device 30, and injects fuel into each cylinder of the engine 11. Hereinafter, the amount of fuel injected by the injector in each 1-pulse fuel injection signal will also be referred to as the fuel injection amount. The fuel injection amount is proportional to the pulse width of the fuel injection signal, and the longer the pulse width, the more the fuel injection amount can be increased.

[0036] In addition, the fuel is supplied to the injectors via an injection pump (not shown). The injection pump supplies the fuel to the injectors at a fuel injection pressure controlled by the control device 30. The fuel injection amount is also proportional to the fuel injection pressure, and the higher the fuel injection pressure, the greater the fuel injection amount. For example, by supplying a fuel injection pressure equal to or greater than a prescribed value (also referred to as injection allowable pressure, refer to Figure 3A and Figure 4 ), the injectors are able to inject fuel into each cylinder of the engine 11.

[0037] The power output from the engine 11 (hereinafter, also simply referred to as the output of the engine 11) is transmitted to the drive wheels DW via a transmission TM mechanically linked to the engine 11, for the vehicle 1 to travel.

[0038] In addition, the engine 11 is also mechanically linked to a motor generator 12. The motor generator 12 is, for example, a three-phase alternating current motor, and functions as a motor that outputs power by being supplied with electric power. Specifically, a rotor (not shown) of the motor generator 12 is linked to the crankshaft 11a of the engine 11. Therefore, the power plant torque output from the power plant including the engine 11 and the motor generator 12 is the sum of the torque output from the engine 11 (hereinafter, also referred to as engine torque) and the torque output from the motor generator 12 (hereinafter, also referred to as motor torque) at the torque at the shaft end of the crankshaft 11a, that is, the crankshaft end torque. Furthermore, in the following description, the positive (+) motor torque is also referred to as power running torque, and the negative (-) motor torque is also referred to as regenerative torque.

[0039] By mechanically linking the engine 11 and the motor generator 12, motor assist is possible in the vehicle 1, that is, the drive of the drive wheels DW using the output of the engine 11 (that is, the travel of the vehicle 1) is assisted using the power output from the motor generator 12 (hereinafter, also simply referred to as the output of the motor generator 12).

[0040] In addition, by mechanically linking the engine 11 and the motor generator 12, it is also possible to rotate drive the motor generator 12 by the output of the engine 11, or to rotate drive the engine 11 by the output of the motor generator 12. Specifically, in the vehicle 1, it is possible to start the engine 11 by the rotation of the crankshaft driven by the motor generator 12.

[0041] The motor generator 12 is electrically connected to a storage battery 20 via a power conversion device 21. The storage battery 20 is, for example, a storage battery having a plurality of storage cells connected in series, and configured to be able to output a prescribed voltage (for example, 50 to 200 [V]). As the storage cell of the storage battery 20, a lithium ion battery, a nickel hydrogen battery, or the like can be used.

[0042] The electric power conversion device 21 has an inverter, a DC / DC converter (none of which is shown), and the like, and is a device that is controlled by the control device 30 to perform electric power conversion. For example, the electric power conversion device 21 converts direct-current electric power supplied from the battery 20 into three-phase alternating-current electric power and supplies the electric power to the motor generator 12, or converts three-phase alternating-current electric power supplied from the motor generator 12 into direct-current electric power and supplies the electric power to the battery 20. The electric power of the battery 20 is supplied to the motor generator 12 via the electric power conversion device 21, whereby the above-described motor assist can be performed.

[0043] In addition, the motor generator 12 also functions as a generator that generates electric power by being rotationally driven. As described above, the motor generator 12 can be rotationally driven by the output of the engine 11, and in addition thereto, the motor generator 12 can be rotationally driven by power input from the drive wheels DW side in association with braking of the vehicle 1 or the like. Electric power generated by the motor generator 12 is supplied to the battery 20 via the electric power conversion device 21, and is used to charge the battery 20.

[0044] The transmission TM is a multi-stage transmission having a plurality of shift stages (for example, seven stages), and is provided in a power transmission path from the engine 11 to the drive wheels DW. Specifically, as shown in FIG. 1, the transmission TM is configured to include a torque converter 13 and a gear box 14. Figure 2

[0045] The torque converter 13 has a pump impeller 131, a turbine 132, a stator 133, and a lock-up clutch 134. The pump impeller 131 is mechanically linked to the engine 11 and the motor generator 12 (specifically, the crankshaft 11a), and rotates integrally in association with the rotational driving of the engine 11 and the motor generator 12. The turbine 132 has a working oil flow inlet that is disposed in proximity to a working oil discharge outlet of the pump impeller 131, and is mechanically linked to and rotates integrally with an input shaft 141 of the gear box 14. The stator 133 is disposed between the turbine 132 and the pump impeller 131, and deflects the flow direction of working oil that is returned from the turbine 132 to the pump impeller 131. In addition, the stator 133 is supported to a housing (not shown) or the like of the torque converter 13 via a one-way clutch 135. By circulating working oil in a circulation path formed between the pump impeller 131 and the turbine 132, the torque converter 13 can transmit power (rotational power) from the pump impeller 131 to the turbine 132 via the working oil.

[0046] The lock-up clutch 134 is a clutch that can disconnect or connect the mechanical connection of the engine 11 and the input shaft 141 of the gear box 14. By making the lock-up clutch 134 in an engaged state, the output of the engine 11 can be directly transmitted to the input shaft 141 of the gear box 14. That is, when the lock-up clutch 134 is in the engaged state, the crankshaft 11a of the engine 11 and the input shaft 141 of the gear box 14 rotate integrally.​

[0047] The transmission 14 has an input shaft 141 to which the output of the engine 11 or the motor generator 12 is transmitted via the torque converter 13, a plurality of shift mechanisms 142, 143 that can variably transmit power to the input shaft 141, and an output member 144 that includes an output gear 144a that outputs power, which is variably transmitted by any one of the plurality of shift mechanisms, to the drive wheels DW side.

[0048] The plurality of shift mechanisms included in the transmission 14 include a first shift mechanism 142 and a second shift mechanism 143. The first shift mechanism 142 has a first shift clutch 142a, a first drive gear 142b that rotates integrally with the input shaft 141 when the first shift clutch 142a is in an engaged state, and a first driven gear 142c that rotates integrally with the output member 144. The second shift mechanism 143 has a second shift clutch 143a, a second drive gear 143b that rotates integrally with the input shaft 141 when the second shift clutch 143a is in an engaged state, and a second driven gear 143c that rotates integrally with the output member 144.

[0049] Further, in Figure 2 , only the first shift mechanism 142 and the second shift mechanism 143 are illustrated as the shift mechanisms included in the transmission 14, but the transmission 14 also includes shift mechanisms (not illustrated) other than the first shift mechanism 142 and the second shift mechanism 143.

[0050] Whether each clutch included in the transmission TM, such as the lock-up clutch 134, the first shift clutch 142a, and the second shift clutch 143a (hereinafter, also simply referred to as the clutches of the transmission TM), is in an engaged state or a disengaged state is controlled by the control device 30.

[0051] Returning to Figure 1 , the control device 30 is a device that controls the engine 11, the transmission TM, the power conversion device 21, and the like. In addition, the control device 30 can also control the motor generator 12 via the control of the power conversion device 21. The control device 30 is realized by, for example, an electronic control unit (ECU: Electronic Control Unit) that includes a processor that performs various calculations, a storage device that stores various information, an input / output device that controls input and output of data between the inside and the outside of the control device 30, and the like. In addition, the control device 30 can be realized by one ECU or by a plurality of ECUs that act in coordination.

[0052] The control device 30 is connected with various sensors, and controls the engine 11, the transmission TM, the electric power conversion device 21 (i.e., the motor generator 12), and the like, based on information input from these various sensors. As the sensors connected with the control device 30, for example, there can be mentioned a rotational speed sensor 17 that detects the rotational speed (hereinafter, also referred to as engine rotational speed) of the engine 11 (crankshaft 11a), and a vehicle speed sensor 18 that detects the speed (hereinafter, also referred to as vehicle speed) of the vehicle 1. Also, as the sensors connected with the control device 30, there can be mentioned an AP sensor that detects the operation amount (hereinafter, referred to as AP opening degree) on the accelerator pedal, a brake sensor that detects the operation amount on the brake pedal, a gear position sensor that detects the shift stage of the transmission TM, a battery sensor that detects the output or temperature of the battery 20, an intake air pressure sensor (none of which is shown in the figure) that detects the intake air pressure of the engine 11, and the like. In addition, the control device 30 can also be connected with an atmospheric pressure sensor (none of which is shown in the figure) that detects the atmospheric pressure.

[0053] For example, the control device 30 derives a target torque (hereinafter, also referred to as crank end required torque) with respect to the sum of the engine torque and the motor torque, i.e., the crank end torque, based on the running state of the vehicle 1. As an example, the control device 30 derives the crank end required torque by referring to the vehicle speed detected by the vehicle speed sensor 18 and the AP opening degree detected by the AP sensor, and a map that determines the crank end required torque required for the running of the vehicle 1 in accordance with the vehicle speed and the AP opening degree. Further, this map is stored in a storage device of the control device 30, for example. Also, the control device 30 controls the engine torque and the motor torque so that the crank end torque becomes the crank end required torque.

[0054] In addition, the control device 30 switches the operation state of the engine 11 between the full cylinder operation and the cylinder deactivation operation, based on the crank end required torque. Specifically, when the crank end required torque is small, the control device 30 controls the engine 11 to perform the cylinder deactivation operation, and when the crank end required torque is large to a certain extent, the control device 30 controls the engine 11 to perform the full cylinder operation. That is, when the crank end required torque is small, the control device 30 controls the engine 11 to perform the cylinder deactivation operation to improve the fuel consumption performance of the vehicle 1, and when the crank end required torque becomes large, the control device 30 controls the engine 11 to perform the full cylinder operation to ensure an appropriate crank end torque corresponding to the running state of the vehicle 1.

[0055] In addition, if a prescribed stop condition is satisfied, the control device 30 executes idle stop control that stops the operation (idling) of the engine 11. As the stop condition, for example, there can be mentioned a condition that the vehicle 1 is in a low speed state or a stop state (i.e., the vehicle speed is below a threshold value) in accordance with a deceleration request to the vehicle 1. The deceleration request is, for example, a brake-on request that the brake pedal of the vehicle 1 is operated (e.g., depressed), an accelerator-off request that the operation of the accelerator pedal of the vehicle 1 is released, or the like.

[0056] In addition, if an acceleration request to the vehicle 1 is present while the operation of the engine 11 is stopped by the idle stop control, the control device 30 starts (i.e., restarts) the engine 11. The acceleration request is, for example, a brake-off request that the operation of the brake pedal of the vehicle 1 is released, an accelerator-on request that the accelerator pedal is operated, or the like.

[0057] At the time of starting the engine 11, the control device 30 starts the engine 11 by the rotation of the crankshaft of the motor generator 12. At the time of starting the engine 11, in order to shorten the period during which vibrations that can cause discomfort to the driver are generated, it is necessary to increase the motoring torque of the motor generator 12 at the time of starting the engine 11, thereby rapidly starting the engine 11. On the other hand, if the motoring torque of the motor generator 12 is maintained even after the engine 11 is started, the engine speed overshoots, resulting in deterioration of the NV (Noise, Vibration) characteristics of the vehicle 1. In addition, if the engine speed thus overshoots, the creep in the vehicle 1 can be too strong, and the vehicle 1 can also jump, which is not desirable for the driver.

[0058] Therefore, in the case where the engine 11 is started by the rotation of the crankshaft of the motor generator 12, before the engine 11 is in a fully combusting (perfectly combusting) state, the control device 30 controls the motoring torque of the motor generator 12 on the basis of the intake air pressure of the engine 11. Specifically, at this time, the control device 30 controls so that the motoring torque becomes a torque obtained by adding a damping torque determined on the basis of the intake air pressure to a crankshaft rotation torque required for the rotation of the crankshaft of the engine 11. As an example, here, the control device 30 determines the damping torque on the basis of the negative pressure amount that is the difference between the intake air pressure and the atmospheric pressure. Thus, it is possible to determine the damping torque having a magnitude corresponding to the compression reaction force of the engine 11.

[0059] Thus, before the engine 11 is in the fully combusting state, the control device 30 controls the motoring torque of the motor generator 12 on the basis of the intake air pressure of the engine 11, whereby it is possible to suppress vibrations that can cause discomfort to the driver and to rapidly start the engine 11. Further, for example, in the case where the engine speed is equal to or greater than a prescribed speed (e.g., 1000 [rpm]), the control device 30 determines that the engine 11 is in the fully combusting state.

[0060] In addition, after the engine 11 is in the full combustion state, the control device 30 controls the regenerative torque of the motor generator 12 based on the fuel injection amount to the engine 11. As an example, the control device 30 controls the regenerative torque with reference to a map in which the fuel injection amount (or the engine torque output from the engine 11 according to the fuel supply based on the fuel injection amount. That is, the combustion torque described later) and the regenerative torque correspond to each other. Further, the map is stored in a storage device of the control device 30, for example, in advance. Then, the control device 30 continues to control the regenerative torque based on the fuel injection amount until the engine speed converges within a prescribed range including a target speed (for example, 1000 [rpm]). Here, the target speed and the prescribed range are set in the control device 30, for example, in advance.

[0061] Specifically, at this time, the control device 30 controls the regenerative torque to match the engine torque (also referred to as combustion torque) output from the engine 11 according to the fuel supply of the injector. Thereby, it is possible to suppress overshooting of the engine speed at the time of starting the engine 11, to suppress deterioration of the NV characteristics of the vehicle 1, or to prevent occurrence of the vehicle 1 flight that the driver does not desire.

[0062] Hereinafter, an example of the control by the control device 30 will be described in detail. Further, each example described below is an example in the case of starting the engine 11 stopped by the idling stop control (that is, re-starting).

[0063]

Throttle Closed Start

[0064] First, with reference to Figure 3A and Figure 3B , an example of starting the engine 11 when the throttle of the vehicle 1 is in the closed state (that is, the state in which the accelerator is closed, hereinafter, also simply referred to as the throttle closed state) will be described. In addition, in Figure 3A , the period relationship of (a) vehicle speed, (b) brake, (c) motor torque, (d) engine speed, (e) intake pressure, (f) fuel injection pressure, (g) fuel injection signal, and (h) ignition signal (that is, the ignition timing of the engine 11) is shown. In addition, in Figure 3B , the motor torque, the engine speed, and the fuel injection signal in a certain period immediately after the period t12 in Figure 3A are shown in an enlarged manner.

[0065] In Figure 3AAt the indicated time t11, since the driver has closed the brakes, in order to start the engine 11, which has been stopped by the idle stop control, the control device 30 begins to rotate the crankshaft of the engine 11 via the electric generator 12. At this time, the control device 30 first sets the control mode of the electric generator 12 to the first mode. Here, the first mode is a control mode determined by controlling the torque of the electric generator 12 based on the intake pressure of the engine 11.

[0066] Then, the control device 30 controls the torque of the electric generator 12 in the first mode until the engine 11 is in a state of complete combustion (see reference). Figure 3A (The part enclosed by the single-dot dashed line indicated by reference numeral 301 in the attached drawing). When set to the first mode in this manner, the control device 30 controls the operation of the electric generator 12 so that the torque for power operation is the torque obtained by adding the crankshaft rotation torque to the damping torque. As a result, the control device 30 can be simplified, reducing its processing burden, suppressing vibrations that may cause discomfort to the driver, and quickly starting the engine 11.

[0067] More specifically, in the first mode, the control device 30 controls the intake air pressure to be as low as possible, thereby increasing the power operating torque of the electric generator 12. This effectively suppresses vibrations caused by the compression reaction force when starting the engine 11. Furthermore, in the first mode, in addition to intake air pressure, the control device 30 can also consider the intake valve closing timing, etc., to control the torque (power operating torque) of the electric generator 12.

[0068] exist Figure 3A At time t12, following time t11, when engine 11 is in a state of complete combustion, control device 30 sets (changes) the control mode of electric generator 12 to the second mode. Here, the second mode is a control mode determined by controlling the torque of electric generator 12 based on the fuel injection quantity, i.e., the pulse width of the fuel injection signal.

[0069] Then, the control device 30 controls the torque of the electric generator 12 in the second mode until the engine speed converges to a specified range (e.g., target speed) (see reference). Figure 3A (The part surrounded by the single-dot dashed line indicated by reference numeral 302). When set to the second mode in this manner, the control device 30 controls the regenerative torque of the electric generator 12 to match the combustion torque. As a result, the control of the control device 30 can be simplified and its processing burden reduced, engine speed overshoot can be suppressed when starting the engine 11, and the deterioration of the NV characteristics of the vehicle 1 can be suppressed, or the undesirable event of the vehicle 1 flying off the road can be prevented.

[0070] Combustion torque may increase proportionally with the fuel injection quantity. Therefore, when the control device 30 controls the regenerative torque based on the fuel injection quantity, the greater the fuel injection quantity, the greater the regenerative torque. Specifically, the longer the pulse width of the fuel injection signal, the greater the fuel injection quantity. Therefore, the longer the pulse width of the fuel injection signal, the greater the regenerative torque that the control device 30 can achieve.

[0071] For example, such as Figure 3B As shown, when the pulse width of the fuel injection signal is w1, the control device 30 controls the regenerative torque to be Tq1. Conversely, when the pulse width of the fuel injection signal is w2, which is shorter than w1, the control device 30 controls the regenerative torque to be Tq2, which is smaller than Tq1. Therefore, the regenerative torque can be controlled in a manner matching the combustion torque, and engine speed overshoot can be suppressed. Furthermore, the higher the fuel injection pressure, the greater the fuel injection quantity. Therefore, it is also possible for the control device 30 to increase the regenerative torque as the fuel injection pressure increases.

[0072] As explained above, when the control device 30 starts the engine 11, which has been stopped by idle stop control, while the throttle is closed, the control device 30 sets the control mode to the first mode to control the power operating torque of the electric generator 12 before the engine 11 is in a state of complete combustion. After the engine 11 is in a state of complete combustion, the control device 30 sets the control mode to the second mode to control the regenerative torque of the electric generator 12. This can prevent the deterioration of the NV characteristics of the vehicle 1 and can properly start the engine 11 by rotating the crankshaft of the electric generator 12.

[0073] In contrast, such as Figure 3A As illustrated in the existing example, if the motor torque is set to 0 after the engine 11 is in full combustion, and no control is performed to match the regenerative torque with the combustion torque, then as shown by the dashed line enclosed by reference numeral 303 in the attached figure, the engine speed exceeds the target speed and overshoots. As a result, NV characteristics deteriorate, or an unwanted vehicle roll-off occurs (during periods when the vehicle speed is >0).

[0074] Alternatively, a method could be considered that derives or measures the engine torque output from engine 11 and controls the regenerated torque to match the derived or measured engine torque. However, in this method, the control of the regenerated torque is delayed relative to the engine torque, and this delay may lead to engine speed overshoot, deterioration of NV characteristics, and potentially, unwanted vehicle ejection.

[0075] In this regard, the control device 30 of the present embodiment controls the regenerative torque based on the fuel injection amount as described above, and thus can suppress a delay in control of the regenerative torque relative to the engine torque, and can control the regenerative torque with high precision to match the engine torque.

[0076]

Throttle open start

[0077] Next, an example in which the engine 11 is started while the throttle of the vehicle 1 is open (i.e., the accelerator is on, hereinafter, also simply referred to as the throttle open state) will be described with reference to Figure 4 , and the same applies to Figure 3A . In Figure 4 , the period relationship of (a) vehicle speed, (b) brake, (c) motor torque, (d) engine speed, (e) intake pressure, (f) fuel injection pressure, (g) fuel injection signal, and (h) ignition signal (i.e., ignition timing of the engine 11) is shown. In the following description of Figure 4 , the description will be focused on the points different from Figure 3A , and the same points as Figure 3A will be appropriately omitted or simplified.

[0078] At the period t21 shown in Figure 4 , since the brake is off and the accelerator is on by the driver, in order to start the engine 11 stopped by the idle stop control, the control device 30 starts to initiate the rotation of the crankshaft of the engine 11 by the motor generator 12. At this time, as in the example of Figure 3A , the control device 30 first sets the control mode of the motor generator 12 to the first mode, and controls the motoring torque of the motor generator 12 by the first mode until the engine 11 is in the fully combusted state (refer to the portion enclosed by the single-dot chain line indicated by reference numeral 401 in Figure 4 ).

[0079] Further, in the throttle open state, the amount of negative pressure of the intake pressure is smaller than in the throttle closed state as shown in Figure 3A , etc. Therefore, the average value of the motoring torque in the period until the engine 11 is in the fully combusted state is larger in the throttle open state than in the throttle closed state.

[0080] At the period t22 after the period t21 shown in Figure 4 , when the engine 11 is in the fully combusted state, the control device 30 sets (changes) the control mode of the motor generator 12 to the second mode, and controls the regenerative torque of the motor generator 12 by the second mode until the engine speed converges within a prescribed range (e.g., target speed) (refer to the portion enclosed by the single-dot chain line indicated by reference numeral 402 in Figure 4 ).

[0081] Furthermore, when the throttle is open, compared to when it is closed... Figure 3A Compared to the throttle closed state, the fuel injection quantity after the engine 11 has just entered a state of complete combustion is increased when the throttle is open. In other words, when the throttle is open, the pulse width of the fuel injection signal after the engine 11 has just entered a state of complete combustion is longer compared to the throttle closed state. Therefore, when the throttle is open, the control device 30 increases the regenerative torque of the engine 11 after it has just entered a state of complete combustion compared to the throttle closed state. As an example, the control device 30 maximizes the regenerative capacity of the electric generator 12 after the engine 11 has just entered a state of complete combustion. In addition, for example, when the throttle is open, the control device 30 also delays the ignition timing of the engine 11 compared to the throttle closed state.

[0082] As explained above, when the control device 30 starts the engine 11, which has been stopped by idle stop control, while the throttle is open, the control device 30 sets the control mode to the first mode to control the power operating torque of the electric generator 12 before the engine 11 is in a state of complete combustion. After the engine 11 is in a state of complete combustion, the control device 30 sets the control mode to the second mode to control the regenerative torque of the electric generator 12. This can prevent the deterioration of the NV characteristics of the vehicle 1 and can properly start the engine 11 by rotating the crankshaft driven by the electric generator 12.

[0083] In contrast, such as Figure 4 As illustrated in the existing example, if the motor torque is set to 0 after the engine 11 is in full combustion, and no control is performed to match the regenerative torque with the combustion torque, then as shown by the dashed line enclosed by reference numeral 403 in the attached figure, the engine speed exceeds the target speed and overshoots. As a result, NV characteristics deteriorate, or an unwanted vehicle roll-off occurs (during periods when the vehicle speed is >0).

[0084] The embodiments of the present invention have been described above, but the present invention is not limited to the above embodiments and can be appropriately modified and improved.

[0085] For example, in the aforementioned embodiments, an example was described where the engine 11, which is stopped by idle stop control, is started. However, the present invention is not limited to this. In other cases where the engine 11 is started, the electric generator 12 can also be controlled in the same way as in the aforementioned embodiments.

[0086] The following are at least the contents described in this specification. Furthermore, the components corresponding to the above embodiments are shown in parentheses, but the present invention is not limited thereto.

[0087] (1) A vehicle control device (control device 30) for controlling a vehicle (vehicle 1) that is provided with an internal combustion engine (engine 11), an electric motor (motor generator 12) linked to the internal combustion engine, and a drive wheel (drive wheel DW) driven by an output of at least one of the internal combustion engine and the electric motor, and that is capable of starting the internal combustion engine by rotation of a crankshaft driven by the electric motor, wherein

[0088] the vehicle control device, in a case where the internal combustion engine is started by rotation of the crankshaft driven by the electric motor, performs the following processing:

[0089] controls a motoring torque of the electric motor based on an intake air pressure of the internal combustion engine before the internal combustion engine is in a fully combusting state,

[0090] controls a regenerative torque of the electric motor based on a fuel injection amount injected to the internal combustion engine after the internal combustion engine is in the fully combusting state until a rotational speed of the internal combustion engine converges within a prescribed range including a target rotational speed.

[0091] According to (1), in a case where the internal combustion engine is started by rotation of the crankshaft driven by the electric motor, the vehicle control device controls a motoring torque of the electric motor based on an intake air pressure of the internal combustion engine before the internal combustion engine is in a fully combusting state, and controls a regenerative torque of the electric motor based on a fuel injection amount injected to the internal combustion engine after the internal combustion engine is in the fully combusting state until a rotational speed of the internal combustion engine converges within a prescribed range including a target rotational speed. Thereby, it is possible to avoid deterioration of NV (Noise, Vibration) characteristics of the vehicle, and to appropriately start the internal combustion engine by rotation of the crankshaft driven by the electric motor.

[0092] (2) The vehicle control device according to (1), wherein

[0093] the vehicle control device is capable of executing an idle stop control that stops an operation of the internal combustion engine when a prescribed stop condition is established,

[0094] the vehicle control device, in a case where the internal combustion engine stopped by the idle stop control is started, performs the following processing:

[0095] controls the motoring torque based on the intake air pressure before the internal combustion engine is in the fully combusting state,

[0096] controls the regenerative torque based on the fuel injection amount after the internal combustion engine is in the fully combusting state until the rotational speed converges within the prescribed range.

[0097] According to (2), in a case where the internal combustion engine stopped by the idling stop control is started, the vehicle control device controls the motoring torque of the electric motor based on the intake pressure before the internal combustion engine is in the fully combusting state, and controls the regenerative torque of the electric motor based on the fuel injection amount after the internal combustion engine is in the fully combusting state until the rotational speed of the internal combustion engine converges within a prescribed range. Thereby, after the idling stop control is performed, it is possible to avoid deterioration of the NV characteristic of the vehicle, and at the same time, it is possible to appropriately start the internal combustion engine by the rotation of the crankshaft driven by the electric motor.

[0098] (3) The vehicle control device according to (1) or (2), wherein

[0099] includes a first mode of controlling the torque of the electric motor based on the intake pressure, and

[0100] a second mode of controlling the torque of the electric motor based on the fuel injection amount,

[0101] before the internal combustion engine is in the fully combusting state, the vehicle control device sets the control mode to the first mode,

[0102] after the internal combustion engine is in the fully combusting state, the vehicle control device sets the control mode to the second mode.

[0103] According to (3), it is possible to appropriately start the internal combustion engine while reducing the processing load by simplifying the control of the vehicle control device.

[0104] (4) The vehicle control device according to any one of (1) to (3), wherein

[0105] in a case where the regenerative torque is controlled based on the fuel injection amount, the more the fuel injection amount, the more the vehicle control device makes the regenerative torque.

[0106] According to (4), it is possible to control the regenerative torque in a manner that matches the torque (combustion torque) of the internal combustion engine that can be increased in proportion to the fuel injection amount, and it is possible to suppress overshooting of the rotational speed of the internal combustion engine.

Claims

1. A vehicle control device for controlling a vehicle, said vehicle comprising: internal combustion engine; An electric motor connected to the internal combustion engine; and A drive wheel driven by the output of at least one of the internal combustion engine and the electric motor. Furthermore, the vehicle can start the internal combustion engine by rotating the crankshaft driven by the electric motor. in, When the internal combustion engine is started by rotating the crankshaft driven by the electric motor, the vehicle control device performs the following processing: Before the internal combustion engine reaches full combustion, the operating torque of the electric motor is controlled based on the intake pressure of the internal combustion engine. After the internal combustion engine is in the state of complete combustion, the regenerative torque of the electric motor is controlled based on the amount of fuel injected into the internal combustion engine until the speed of the internal combustion engine converges to a specified range including the target speed.

2. The vehicle control device according to claim 1, wherein, When the specified stopping conditions are met, the vehicle control device can perform idle stop control to stop the operation of the internal combustion engine. When the vehicle control device starts the internal combustion engine that has been stopped by the idle stop control, it performs the following processing: Before the internal combustion engine reaches the state of complete combustion, the power operating torque is controlled based on the intake pressure. After the internal combustion engine is in the state of complete combustion, the regenerative torque is controlled based on the fuel injection quantity until the speed converges to the specified range.

3. The vehicle control device according to claim 1 or 2, in, include: A first mode based on the intake pressure to control the torque of the electric motor; and A second mode that controls the torque of the electric motor based on the fuel injection quantity. Before the internal combustion engine reaches the state of complete combustion, the vehicle control device sets the control mode to the first mode. After the internal combustion engine is in the state of complete combustion, the vehicle control device sets the control mode to the second mode.

4. The vehicle control device according to claim 1 or 2, wherein, When the regenerative torque is controlled based on the fuel injection quantity, the greater the fuel injection quantity, the greater the regenerative torque is achieved by the vehicle control device.

5. The vehicle control device according to claim 3, wherein, When the regenerative torque is controlled based on the fuel injection quantity, the greater the fuel injection quantity, the greater the regenerative torque is achieved by the vehicle control device.

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