JP7438637B2 - Hybrid vehicle control device - Google Patents

Description

The present invention relates to a control device for controlling a hybrid vehicle equipped with a driving electric motor and an internal combustion engine.

In recent years, hybrid vehicles equipped with two types of power sources, an electric motor and an internal combustion engine, have become popular to a certain extent. A series type hybrid vehicle (for example, refer to the following patent document) generates electricity by driving a power generation motor generator with an internal combustion engine, and stores the generated electricity in a power storage device, such as a lithium ion secondary battery or a nickel metal hydride secondary battery. It is stored in a battery and/or a capacitor such as the like, and is supplied to a motor generator for driving. Then, the driving motor generator rotates the drive wheels of the vehicle to drive the vehicle.

Not only the power generation motor generator but also the driving motor generator can generate power by regenerative braking, and the generated power can be stored in the power storage device. If the power storage device has already stored electric charge to its full capacity, the electric power obtained through regenerative braking is purposely supplied to the power generation motor generator, which operates as an electric motor to perform motoring that rotates and drives the internal combustion engine. This consumes excess electricity.

In a hybrid vehicle, it is possible to drive the vehicle using the rotational driving force output from the driving motor generator without performing firing in which the internal combustion engine burns fuel to generate rotational driving force. Therefore, even when the vehicle is in operation, the internal combustion engine may continue to stop rotating.

When the amount of charge stored in the power storage device decreases, or when the required output from the motor generator for driving is large, the internal combustion engine is started, fuel is supplied to the cylinders, and the fuel is combusted. The power drives the power generation motor generator, generates power, charges the power storage device, or increases the power supplied to the travel motor generator.

In a series hybrid vehicle, the power generation motor generator also serves to motor, ie crank, the internal combustion engine in preparation for starting the stopped internal combustion engine. During cranking, the necessary power is supplied from the power storage device.

JP 2019-131035 Publication

When starting a stopped internal combustion engine and driving the power generation motor generator to generate electricity, cranking is first performed to start the internal combustion engine so that the engine can rotate independently. If so, end the cranking. Thereafter, the power generated by the power generation motor generator driven by the internal combustion engine is increased from zero.

In the above process, it is customary to provide a transition period between the end of cranking and the start of power generation, during which firing of the internal combustion engine is performed while the power generated by the power generation motor generator remains at zero. It has become.

The reason for providing the transient period is to wait for the combustion of fuel in the combustion chamber of the cylinder of the internal combustion engine to become sufficiently stable before starting power generation by the power generation motor generator, that is, increasing the engine load. This is to prevent engine stall and achieve reliable power generation control. In addition, while the internal combustion engine is not firing, its exhaust passage and exhaust purification catalyst are filled with oxygen, and the temperature of the catalyst also decreases. These events reduce the efficiency of the catalyst in purifying harmful substances in the exhaust gas. The transition period is also a period in which excess oxygen in the catalyst is purged by maintaining the minimum exhaust flow rate and the temperature of the catalyst is increased, thereby suppressing an increase in emissions of harmful substances.

The main trigger for starting a stopped internal combustion engine is when the driver of the vehicle depresses the accelerator pedal to request acceleration of the vehicle. In order to accelerate the vehicle, it is necessary to increase the output of the driving motor generator, and for this purpose, a necessary and sufficient amount of electric power must be supplied to the driving motor generator.

When the amount of depression of the accelerator pedal by the driver is not large and gradual acceleration is required, even if the start of power generation by the power generation motor generator is delayed due to the existence of a transition period after starting the internal combustion engine, the on-board power storage The device can supply the power consumed by the driving motor generator to meet demand.

However, when the amount of depression of the accelerator pedal by the driver is large and rapid acceleration is required, the power storage device may not be able to sufficiently supply the electric power consumed by the driving motor generator. In this case, it becomes necessary for the power generation motor generator to generate electricity to compensate for the shortage of power, but during the above transition period, no power is generated, and the driving force output from the driving motor generator does not meet the acceleration request. The driver will not be able to obtain the desired acceleration response.

The present invention has been made by focusing on the above problem, and in a vehicle in which the internal combustion engine drives a generator and the generated electric power is supplied to the driving electric motor, the combustion of fuel immediately after the internal combustion engine starts. The intended purpose is to achieve both stabilization of the vehicle and suppression of harmful substance emissions, as well as the acceleration response desired by the driver.

In the present invention, an internal combustion engine is used to burn fuel and operate the engine, the internal combustion engine drives a generator, the generated electric power is supplied to the electric motor for driving, and the driving force output by the electric motor for driving is supplied to the driving wheels. There is a cranking period in which fuel is supplied and combusted while the internal combustion engine is rotated by an electric motor in order to start a stopped internal combustion engine, and internal combustion The intake air of the internal combustion engine compared to the power generation period during which the internal combustion engine is operated by burning fuel with the opening of the throttle valve on the intake passage of the engine further expanded and the generator generates electricity. The length of the transition period in which the internal combustion engine is operated by burning fuel with the opening of the throttle valve on the passageway further reduced, but the generator does not generate electricity, is determined by the amount of time the driver presses the accelerator pedal at that time. A control device for a hybrid vehicle that expands or contracts in accordance with the amount of driving force required for the electric motor for driving has been constructed.

Note that with regard to "expanding or contracting the length of the transition period," the length of the transition period may be set to substantially 0, and power generation may be started immediately after the cranking period ends in the power generation period.

In addition, after the cranking period for starting the internal combustion engine ends and the transition period begins, the transition period changes from the transient period to the power generation period, with the necessary condition that the air-fuel ratio of the gas flowing through the exhaust passage of the internal combustion engine reaches a predetermined value. It is also possible to take the form of transitioning to .

According to the present invention, in a vehicle in which electric power generated by driving a generator with an internal combustion engine is supplied to a driving electric motor, stabilization of fuel combustion immediately after starting the internal combustion engine and suppression of emission of harmful substances, It is possible to achieve both the acceleration response desired by the driver.

1 is a diagram showing a schematic configuration of a series-type hybrid vehicle and a control device according to an embodiment of the present invention. FIG. 3 is a diagram showing an outline of an internal combustion engine installed in the hybrid vehicle of the embodiment. FIG. 3 is a flow diagram showing an example of a procedure of processing executed by the control device according to the embodiment according to a program. FIG. 4 is a timing diagram showing a pattern of control performed by the control device of the embodiment.

An embodiment of the present invention will be described with reference to the drawings. FIG. 1 shows a schematic configuration of the main systems of a hybrid vehicle in this embodiment. This hybrid vehicle includes an internal combustion engine 1, a power generation motor generator 2 that is driven by the internal combustion engine 1 to generate electricity, a power storage device 3 that stores the power generated by the power generation motor generator 2, and the power generation motor generator 2 and/or the power generation motor generator 2. Alternatively, it includes a driving motor generator 4 that receives power from the power storage device 3 and drives the drive wheels 62 of the vehicle.

The hybrid vehicle of this embodiment is a series hybrid electric vehicle that uses the internal combustion engine 1 only for power generation, and the drive wheels 62 of the vehicle are exclusively supplied with driving force for running from the running motor generator 4. The internal combustion engine 1 and the drive wheels 62 are mechanically separated, and originally no rotational driving force is transmitted between them. Therefore, the internal combustion engine 1 can rotate completely independently of the driving motor generator 4 and the drive wheels 62, and can also stop completely independently. Therefore, even when the vehicle is in operation with the ignition switch (power switch or ignition key) turned ON and the vehicle is ready to run when the driver depresses the accelerator pedal, the power storage device 3 is not fully charged. In a situation where electric charges are stored and the brake booster 15 stores sufficient negative pressure, the internal combustion engine 1 may not be operated with fuel combustion.

A crankshaft, which is a rotating shaft of the internal combustion engine 1, is mechanically connected to a rotating shaft of a power generation motor generator 2 via a gear mechanism. Then, by inputting the rotational driving force output by the internal combustion engine 1 to the power generation motor generator 2, the power generation motor generator 2 generates power. The generated electric power is charged to the power storage device 3 and/or supplied to the motor generator 4 for driving. The power generation motor generator 2 also functions as a motoring electric motor that generates rotational driving force and rotationally drives the crankshaft of the internal combustion engine 1. For example, the power generation motor generator 2 performs cranking in preparation for starting the stopped internal combustion engine 1.

The driving motor generator 4 generates driving force for driving the vehicle, and inputs the driving force to the driving wheels 62 via the reduction gear 61. Further, the driving motor generator 4 generates electricity by being rotated by the driving wheels 62, and recovers the kinetic energy of the vehicle as electrical energy. The electric power generated by this regenerative braking charges the power storage device 3.

However, if the power storage device 3 has already been charged to its full capacity and it is difficult to charge it further, the electric power regenerated by the driving motor generator 4 may be supplied to the power generating motor generator 2 to generate electricity. The motor generator 2 is operated as an electric motor to rotationally drive the internal combustion engine 1. This allows excess power to be used up while maintaining the vehicle's braking performance. Further, at this time, since the rotation of the internal combustion engine 1 is maintained, a fuel cut in which the fuel supply to the cylinders of the internal combustion engine 1 is temporarily stopped can be executed.

The generator inverter 21 converts AC power generated by the power generation motor generator 2 into DC power. Then, the DC power is input to the power storage device 3 or the drive inverter 41. Furthermore, when operating the power generation motor generator 2 as an electric motor, the generator inverter 21 converts the DC power supplied from the power storage device 3 and/or the drive inverter 41 into AC power, and then converts the power generation motor generator 2 into AC power. Enter.

The drive inverter 41 converts the DC power supplied from the power storage device 3 and/or the generator inverter 21 into AC power, and inputs the AC power to the driving motor generator 4 . Furthermore, the drive inverter 41 converts the AC power generated by the driving motor generator 4 into DC power when performing regenerative braking of the vehicle, and inputs the DC power to the power storage device 3 or the generator inverter 21 . The generator inverter 21 and the drive inverter 41 form part of a PCU (Power Control Unit).

Power storage device 3 is a battery, a capacitor, or the like. The battery is a high voltage secondary battery with high energy density, such as a lithium ion secondary battery or a nickel hydride secondary battery. The power storage device 3 charges and stores electric power generated by each of the power generation motor generator 2 and the traveling motor generator 4. In addition, the power storage device 3 discharges electric power for operating each of the power generation motor generator 2 and the traveling motor generator 4 as electric motors, and supplies necessary electric power to these motor generators 2 and 4.

FIG. 2 shows an outline of the internal combustion engine 1 installed in the hybrid vehicle of this embodiment. The internal combustion engine 1 is a spark ignition four-stroke engine, and includes a plurality of cylinders 11 (for example, three cylinders, one of which is shown in FIG. 1). An injector 111 is provided near the intake port of each cylinder 11 to inject fuel toward the intake port. Furthermore, a spark plug 112 is attached to the ceiling of the combustion chamber of each cylinder 11. The spark plug 112 causes a spark discharge between a center electrode and a ground electrode upon application of an induced voltage generated in an ignition coil.

The intake passage 13 for supplying intake air takes in air from the outside and guides it to the intake port of each cylinder 11. On the intake passage 13, an air cleaner 131, an electronic throttle valve 132, a surge tank 133, and an intake manifold 134 are arranged in this order from upstream. The air cleaner 131 is located at the most upstream position in the intake passage 13, that is, at the intake port that takes in air. The intake port opens at the front of the vehicle to take in cold air and improve the charging efficiency of the internal combustion engine.

The exhaust passage 14 for discharging exhaust gas guides exhaust gas generated as a result of burning fuel within the cylinders 11 from the exhaust port of each cylinder 11 to the outside. An exhaust manifold 142 and a three-way catalyst 141 for purifying exhaust gas are arranged on the exhaust passage 14.

An ECU (Electronic Control Unit) 0, which is a control device that controls the internal combustion engine 1, the power generation motor generator 2, the power storage device 3, the inverters 21 and 41, and the driving motor generator 4, includes a processor, memory, input interface, output interface, etc. It is a microcomputer system with The ECU0 includes a plurality of ECUs, namely an EFI (Electronic Fuel Injection) ECU01 that controls the internal combustion engine 1, a generator ECU02 that controls the power generation motor generator 2 and the generator inverter 21, and a BMS (Battery Management) that controls the power storage device 3. System) ECU 03, drive machine ECU 04 that controls the driving motor generator 4 and drive machine inverter 41, etc., and HV (Hybrid Vehicle) ECU 00, which is a higher-level controller that controls these, are connected to CAN (Controller Area Network), etc. They are communicably connected to each other via telecommunication lines.

For the ECU 0, a vehicle speed signal a is output from a vehicle speed sensor that detects the actual vehicle speed, and a crank angle signal b is output from a crank angle sensor that detects the rotation angle and engine speed of the crankshaft of the internal combustion engine 1. , an accelerator opening signal output from a sensor that detects the amount of depression of the accelerator pedal by the driver as the accelerator opening (in other words, the driving force that the driver requests for the vehicle (the traveling motor generator 4)) c, an intake temperature/intake pressure signal e output from a temperature/pressure sensor that detects the intake air temperature and intake pressure in the intake passage 13 (in particular, the surge tank 133 or the intake manifold 134) of the internal combustion engine 1; A cooling water temperature signal f output from a water temperature sensor that detects the temperature of the cooling water, and a battery SOC ( A state of charge) signal g, a negative pressure signal h output from a negative pressure sensor that detects the negative pressure stored in the constant pressure chamber of the brake booster 15, and a state of charge signal h output from a negative pressure sensor that detects the negative pressure stored in the constant pressure chamber of the brake booster 15; An air-fuel ratio sensor signal m output from an air-fuel ratio sensor (linear A/F sensor or O ₂ sensor) that detects the fuel ratio is input.

The ECU0 detects the amount of accelerator pedal depression operated by the driver, the shift position, that is, the position of the shift lever or selector lever, the current vehicle speed, the slope of the road surface, and the power storage device, which are sensed through various sensors. The rotational driving force output by the driving motor generator 4 and the internal combustion engine 1 depend on the amount of charge stored in the motor generator 3, the magnitude of the negative pressure stored in the brake booster 15, the generated power of the motor generator 2 for power generation, etc. The rotational driving force outputted by the power generating motor generator 2 and the magnitude of the electric power generated by the power generating motor generator 2 are controlled to increase or decrease.

In principle, if the power storage device 3 currently stores sufficient charge and the output required for the driving motor generator 4 is small, the fuel supply to the internal combustion engine 1 is cut off and the internal combustion engine 1 is operated. do not. On the other hand, if the amount of charge stored in the power storage device 3 is less than the threshold value, or if the output required for the driving motor generator 4 is large, the internal combustion engine 1 is started and fuel is supplied to the cylinder 11. Firing is performed to burn this, and the rotational driving force output from the internal combustion engine 1 drives the generator motor generator 2 to generate electricity to charge the power storage device 3 or supply it to the motor generator 4 for driving. Increase power.

FIG. 3 shows a procedure of processing executed by the ECU 0 when starting and operating the internal combustion engine 1 that has been stopped. The internal combustion engine 1 is started while the internal combustion engine 1 is not being operated by supplying fuel to the cylinders 11 of the internal combustion engine 1 and the driving motor generator 4 is driving the drive wheels 62 to drive the vehicle. In order to perform power generation by the power generation motor generator 2 (step S1), first, the power generation motor generator 2 is operated as an electric motor, and thereby cranking is performed to start the internal combustion engine 1 ( Step S2). Then, after the crankshaft of the internal combustion engine 1 has rotated for a predetermined number of times or more or for a predetermined angle or more, and cylinder discrimination for learning the current stroke or piston position of each cylinder 11 of the internal combustion engine 1 has been completed, each cylinder of the internal combustion engine 1 Fuel is injected at an appropriate timing in accordance with the stroke of step 11, and firing is started to ignite and burn the fuel at an appropriate timing. The rotation angle and rotation speed of the crankshaft of the internal combustion engine 1, that is, the engine rotation speed, can be detected (in the generator ECU 02) via a resolver attached to the power generation motor generator 2, and the crank angle and rotation speed attached to the internal combustion engine 1 can be detected. It can also be detected via a sensor (at the EFI ECU01).

The opening degree of the throttle valve 132 during the cranking period in step S2 is opened to such an extent that the minimum amount of air necessary for starting the internal combustion engine 1 is sucked into the cylinder 11 (rather than fully open). The fuel injection amount during the cranking period is adjusted so that the air-fuel ratio of the air-fuel mixture filled into the cylinder 11 is richer than the stoichiometric air-fuel ratio.

Once the internal combustion engine 1 has started to rotate independently (step S3), in other words, the engine speed can maintain an upward trend even after reducing the output of the power generation motor generator 2. The output of the power generation motor generator 2 operated as an electric motor is reduced to 0 to complete cranking (step S4), and thereafter the power generation motor generator 2 is rotationally driven by the internal combustion engine 1.

After cranking ends, a transition period begins. The transition period is a period in which the power generation motor generator 2 is operated under no load, in which the power generation amount (output voltage or output current) by the power generation motor generator 2 is not increased from 0 even though the internal combustion engine 1 is fired. The purpose of providing the transition period is to wait for the combustion of fuel in the combustion chamber of the cylinder 11 to become sufficiently stable, and to prevent the engine from stalling after the start of power generation. In addition, while the internal combustion engine 1 is not firing, the exhaust passage 14 and the catalyst 141 are filled with oxygen, and the temperature of the catalyst 141 also decreases. All of these reduce the efficiency of purifying harmful substances in the exhaust gas by the catalyst 141. The transition period is also useful for maintaining a minimum exhaust flow rate to purge excess oxygen in the catalyst 141, promoting temperature rise of the catalyst 141, and suppressing an increase in the emission of harmful substances.

During the transition period, the throttle valve 132 is opened to such an extent that the minimum amount of air required to maintain the rotation of the internal combustion engine 1 is sucked into the cylinder 11 (rather than fully open). The fuel injection amount during the transient period is adjusted so that the air-fuel ratio of the air-fuel mixture filled into the cylinder 11 is at or near the stoichiometric air-fuel ratio.

Once the internal combustion engine 1 is in a state where it can stably output the rotational driving force necessary for power generation (step S5), the power generation motor generator 2 is operated as a generator to generate the generated power. It is increased from 0 (step S6).

The condition for transitioning from the transition period to the power generation period in step S5 is, for example, that a required delay time has elapsed since the end of cranking. As will be described later, this delay time can be expanded or contracted depending on the amount of depression of the accelerator pedal by the driver, which triggered starting the stopped internal combustion engine 1, or the required driving force or output for the driving motor generator 4. do. Note that the delay time may be set to substantially 0, that is, the transition period may not be substantially provided, and power generation may be started immediately after the end of cranking.

Alternatively, the condition for transitioning from the transition period to the power generation period may be that the air-fuel ratio of the gas flowing through the exhaust passage 14 of the internal combustion engine 1 reaches a predetermined value. During the cranking period and immediately after the end of cranking, the gas flowing through the exhaust passage 14 and flowing into the catalyst 141 contains a large amount of oxygen, and its air-fuel ratio is leaner than the stoichiometric air-fuel ratio. After the transition to the transition period, the air-fuel ratio of the gas flowing through the exhaust passage 14 and flowing into the catalyst 141 gradually approaches the stoichiometric air-fuel ratio from lean. When the air-fuel ratio of the gas detected via the air-fuel ratio sensor installed in the exhaust passage 14 reaches the stoichiometric air-fuel ratio or a predetermined value close to it, the fuel is stably combusted in the combustion chamber of the cylinder 11. The transition period ends and the power generation period begins.

In step S5, if both the required delay time has elapsed since the end of cranking and the air-fuel ratio of the gas flowing through the exhaust passage 14 has reached a predetermined value, the transition period shifts to the power generation period. (AND condition), or it may be possible to transition from the transition period to the power generation period if at least one of them is satisfied (OR condition).

During the power generation period of step S6, the magnitude of the electric power generated by the power generation motor generator 2 corresponds to the electric power demand of the vehicle, including the required driving force or required output for the traveling motor generator 4. The opening degree of the throttle valve 132 during the power generation period becomes larger as the electric power to be generated by the power generation motor generator 2 increases, that is, as the required driving force or required output for the traveling motor generator 4 increases. Needless to say, as the opening degree of the throttle valve 132 increases, the amount of air taken into the cylinder 1 and the amount of fuel injection increase, and the driving force and output that the internal combustion engine 1 provides to the power generation motor generator 2 increases. The fuel injection amount during the power generation period is adjusted so that the air-fuel ratio of the air-fuel mixture filled into the cylinder 11 is at or near the stoichiometric air-fuel ratio.

Incidentally, the EFI ECU01, which forms part of the ECU0, acquires various information a, b, c, d, e, f, g, h, and m necessary for operational control of the internal combustion engine 1 via an input interface, and controls the engine. The rotational speed is acquired and the amount of air taken into the cylinder 11 is estimated. Then, the required fuel injection amount commensurate with the intake air amount (necessary to realize the target air-fuel ratio), fuel injection timing (including the number of fuel injections for one combustion), fuel injection pressure, and ignition timing (one time The operating parameters of the internal combustion engine 1, such as the number of ignitions for combustion), the required EGR rate (or EGR gas amount), etc., are determined. This EFI ECU01 outputs various control signals i, j, k, l corresponding to operating parameters to the igniter of the spark plug 112, the injector 111, the throttle valve 132, the EGR valve 123, etc. via the output interface.

FIG. 4 shows how the cranking period, transition period, and power generation period for starting the internal combustion engine 1 are controlled. In FIG. 4, the thin solid line indicates a case where the amount of depression of the accelerator pedal by the driver is relatively small, the driving force or output required of the driving motor generator 4 is relatively small, and slow acceleration with small acceleration should be achieved. represents. After a time t ₀ when the driver starts to press the accelerator pedal, cranking is performed to start the internal combustion engine 1 that has been stopped. Then, after time t ₁ when starting of internal combustion engine 1 is completed and cranking ends, until time t ₂ is defined as a transition period, internal combustion engine 1 is fired and operated without power generation by power generation motor generator 2 .

At time _t2 , the conditions for transitioning from the transient period to the power generation period are satisfied, and the power generated by the power generation motor generator is increased from 0 to start power generation. At this time, an operation is performed to enlarge the opening degree of the throttle valve 132 compared to that during the transition period, and the amount of air and fuel injection taken into the cylinder 11, and the amount of air output from the internal combustion engine 1 and input to the motor generator 2 for power generation, are performed. The driving force during the transition period is increased.

The length of the transition period from time t ₁ to time t ₂ , that is, the delay time from the end of cranking to the start of power generation, depends on the amount of depression of the accelerator pedal by the driver, the driving force required for the motor generator 4 for driving, or the amount of time the driver presses the accelerator pedal. Change depending on the size of the output. For example, in the case of a slow acceleration request where the amount of accelerator pedal depression or the required driving force or output is less than a certain threshold, the delay time is set to a predetermined value (about several hundred milliseconds to several seconds), and the amount of accelerator pedal depression or required driving force or output is less than a certain threshold. In the case of a sudden acceleration request in which the required driving force or output is equal to or greater than the threshold value, the delay time is set to a smaller value (which may be 0 or a minimum value close to 0).

Alternatively, the delay time may be shortened as the amount of depression of the accelerator pedal or the required driving force or output increases.

In FIG. 4, the thick broken line represents a case where the amount of depression of the accelerator pedal by the driver is large, the driving force or output required of the driving motor generator 4 is large, and sudden acceleration with large acceleration should be achieved. . In this case as well, after the time t ₀ when the driver begins to press the accelerator pedal, cranking is performed to start the internal combustion engine 1 that has been stopped.

The difference from the case of a slow acceleration request is that after the start of the internal combustion engine 1 is completed and cranking is finished, time _t1 , the generation period begins as soon as possible, and the power generation motor generator 2 starts generating electricity. At the point. In the illustrated example, the transition period between the cranking period and the power generation period is set to substantially 0, that is, the length of the delay time from the end of cranking to the start of power generation is set to 0 or a minimum value close to 0, Immediately after the cranking end time _t1 , the power generated by the power generation motor generator 2 is increased. The opening degree of the throttle valve 132 at this time is not only larger than that during the transition period, but also larger than the opening degree during the power generation period when slow acceleration is requested. In other words, the larger the amount of depression of the accelerator pedal by the driver, the larger the opening degree of the throttle valve 132 during the power generation period, and the larger the amount of air taken into the cylinder 11 and the amount of fuel injection.

In this embodiment, the internal combustion engine 1 burns fuel and operates the internal combustion engine 1, and the internal combustion engine 1 drives the generator 2 to supply the generated electric power to the electric motor 4 for driving, and the electric motor 4 for driving outputs the driving force. A cranking period in which power is supplied to the drive wheels 62 to control the running vehicle, and fuel is supplied and burned while the electric motor 2 rotates the internal combustion engine 1 in order to start the stopped internal combustion engine 1. and a power generation period in which the internal combustion engine 1 is operated by burning fuel with the opening degree of the throttle valve 132 on the intake passage 13 of the internal combustion engine 1 being expanded more than the cranking period, and the generator 2 generates power. The generator 2 generates electricity while operating the internal combustion engine 1 by burning fuel with the opening degree of the throttle valve 132 on the intake passage 13 of the internal combustion engine 1 being more reduced than during the power generation period between A control device 0 for a hybrid vehicle is configured in which the length of a transition period in which no operation is performed is expanded or contracted according to the amount of depression of the accelerator pedal by the driver or the magnitude of the driving force required of the electric motor 4 for driving at that time.

According to the present embodiment, in the case of a slow acceleration request in which the amount of depression of the accelerator pedal by the driver is relatively small, a transition period similar to the conventional one is provided after starting the internal combustion engine 1 and before starting power generation by the generator 2. , it is possible to stabilize the combustion of fuel in the internal combustion engine 1 and to suppress an increase in emissions of harmful substances immediately after the internal combustion engine 1 is started. On the other hand, in the case of a sudden acceleration request that requires a large amount of depression of the accelerator pedal by the driver, the transition period is shortened or eliminated, and the generator 2 starts generating electricity as soon as possible, and the electric motor for driving 4 can be sufficiently increased, and it becomes possible to achieve the acceleration response desired by the driver.

In addition, after completing the cranking period for starting the internal combustion engine 1 and transitioning to the transition period, the transient By making the transition from the period to the power generation period, it is possible to start power generation by the generator 2 after ensuring the stability of fuel combustion in the combustion chamber of the cylinder 11, and to reduce the load on the generator 2. The risk of a drop in engine speed due to the increase is further reduced.

Note that the present invention is not limited to the embodiments detailed above. In particular, the object to which the present invention is applied is not limited to series-type hybrid vehicles.

In addition, the specific configuration and processing contents of each part can be variously modified without departing from the spirit of the present invention.

The present invention can be applied to control of hybrid vehicles.

0...Control unit (ECU)
1... Internal combustion engine 13... Intake passage 132... Throttle valve 2... Generator, motoring motor (power generation motor generator)
3...Power storage device 4...Travel electric motor (travel motor generator)
62...Drive wheel

Claims (2)

The internal combustion engine burns fuel to drive the vehicle, the internal combustion engine drives a generator, the generated electricity is supplied to the electric motor for driving, and the driving force output from the electric motor for driving is supplied to the drive wheels to drive the vehicle. It controls the vehicle,
In order to start a stopped internal combustion engine, an electric motor rotates the internal combustion engine while supplying fuel and combusts it.Compared to the cranking period, the opening degree of the throttle valve on the intake passage of the internal combustion engine is made smaller. A state in which the opening degree of the throttle valve on the intake passage of the internal combustion engine is reduced more than during the power generation period, during which the internal combustion engine is operated by burning fuel in an expanded state and the generator generates electricity. The length of the transition period in which the internal combustion engine is operated by burning fuel at the time, but the generator does not generate electricity, is determined by the amount of accelerator pedal depression by the driver at that time or the amount of driving force required of the electric motor for driving. A hybrid vehicle control device that expands and contracts according to the weather. After completing the cranking period for starting the internal combustion engine and transitioning to the transition period, the transition period transitions to the power generation period with the necessary condition that the air-fuel ratio of the gas flowing through the exhaust passage of the internal combustion engine reaches a predetermined value. The control device for a hybrid vehicle according to claim 1.

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