WO2023181285A1

WO2023181285A1 - Hybrid vehicle

Info

Publication number: WO2023181285A1
Application number: PCT/JP2022/014067
Authority: WO
Inventors: 京太郎小山; 洋史矢倉; 宏樹林
Original assignee: 三菱自動車工業株式会社
Priority date: 2022-03-24
Filing date: 2022-03-24
Publication date: 2023-09-28

Abstract

Disclosed is a hybrid vehicle (1) comprising an engine (2), a motor (3) for driving the wheels and carrying out regenerative braking, a generator (4) for generating power by means of the driving force of the engine (2) and driving the engine (2), and a battery (5) connected to the motor (3) and the generator (4). In addition, this hybrid vehicle comprises a control device (10) for executing a regenerative motoring control wherein regenerative power of the motor (3) is supplied to the generator (4) and the engine (2) is motored at a prescribed target rotation speed during driving while the accelerator is off. The control device (10) stops regenerative motoring control when the accelerator is on during regenerative motoring control, and executes a first power generation control for causing the generator (4) to generate power while firing of the engine (2) is carried out, with the rotation speed of the engine fixed at the target rotation speed at that point in time.

Description

hybrid vehicle

This case relates to a hybrid vehicle that implements regenerative motoring control.

Hitherto, hybrid vehicles have been known that can obtain regenerative braking force by charging a battery with regenerative power generated in a driving motor. In this type of hybrid vehicle, there is a risk that regenerative braking power may not be obtained if the battery charging is restricted (for example, when the battery is near full charge or when the battery fails). . Therefore, a control (regenerative motoring control) has been proposed that balances the power balance by causing a motor other than the travel motor to consume regenerative power and idle the engine. Through such control, regenerative braking force can be ensured while limiting charging of the battery (see, for example, Patent Document 1).

Japanese Patent Application Publication No. 2020-049974

In the regenerative motoring control described above, the rotational speed when the engine is idle is set according to the magnitude of the regenerative power. On the other hand, if the engine starting conditions are met when the accelerator pedal is pressed during regenerative motoring control and regenerative power generation ends, the engine will rotate independently at a rotation speed that corresponds to the accelerator opening. controlled by. This causes a problem in that the rotational speed of the engine changes rapidly, which may give a sense of discomfort to the driver.

For example, if the accelerator pedal is lightly depressed in a situation where the engine rotational speed is relatively high during regenerative motoring control, the engine rotational speed may suddenly decrease, causing engine noise and vibration to become extremely low. At this time, the driver feels as if the engine is sluggish even though he/she is trying to accelerate the vehicle. Therefore, the driver feels that the operation of the vehicle and the actual behavior of the vehicle are not in harmony, and a good driving feeling cannot be obtained.

One of the purposes of this invention, which was created in light of the above-mentioned issues, is to provide a hybrid vehicle that can improve the driving feeling. In addition, this purpose is not limited to this purpose, and it is also possible to achieve effects derived from each configuration shown in "Details for Carrying Out the Invention" that will be described later, which cannot be obtained with conventional techniques. It is positioned as a purpose.

The disclosed hybrid vehicle can be realized as the embodiments or application examples disclosed below, and solves at least part of the above problems.
The disclosed hybrid vehicle includes an engine, a motor that drives wheels and performs regenerative braking, a generator that generates electricity using the driving force of the engine and drives the engine, and a battery that is connected to the motor and the generator. Be prepared. The vehicle also includes a control device that performs regenerative motoring control that supplies regenerative power of the motor to the generator while the vehicle is running and the accelerator is off to motor the engine at a predetermined target rotational speed. The control device stops the regenerative motoring control when the accelerator is turned on while the regenerative motoring control is being performed, and controls the firing of the engine while fixing the engine rotational speed to the target rotational speed at that time. A first power generation control is performed in which the generator is caused to generate power while performing the first power generation control.

According to the disclosed hybrid vehicle, when the accelerator is turned on while regenerative motoring control is being performed, regenerative motoring control is stopped and first power generation control is performed. The first power generation control is control that causes the generator to generate power while firing the engine while keeping the engine rotation speed fixed at the target rotation speed at that time. By implementing such first power generation control, it is possible to suppress fluctuations in engine speed during the transition process from regenerative motoring control to first power generation control, and the generator can be controlled without changing engine noise or vibration. power generation can be carried out. Therefore, the drive feeling during acceleration from regenerative motoring control can be improved.

FIG. 1 is a block diagram showing the configuration of a hybrid vehicle. It is a graph illustrating the relationship between accelerator opening and driver requested output. It is a graph which illustrates the relationship between vehicle speed and target rotational speed of an engine. It is a flowchart which illustrates the flow of first power generation control and second power generation control. It is a time chart illustrating the effect of the first power generation control and the second power generation control. It is a graph illustrating the output characteristics of an engine.

The disclosed hybrid vehicle can be implemented by the following embodiments.

[1. Device configuration]
FIG. 1 is a block diagram illustrating the configuration of a hybrid vehicle 1 as an example. This hybrid vehicle 1 (also simply referred to as vehicle 1) is a hybrid vehicle (hybrid electric vehicle, HEV, Hybrid Electric Vehicle) or plug-in hybrid electric vehicle (PHEV, Plug-in Hybrid Electric Vehicle). A plug-in hybrid vehicle means a hybrid vehicle in which the battery 5 can be externally charged or power can be externally supplied from the battery 5. Plug-in hybrid vehicles are equipped with a charging port (inlet) into which a charging cable that supplies power from an external charging facility is inserted, and an outlet (outlet) for external power supply.

The engine 2 is, for example, an internal combustion engine such as a gasoline engine or a diesel engine. A generator 4 is connected to the drive shaft of the engine 2 . The generator 4 is a generator (electric motor/generator) that has both the function of driving the engine 2 with the electric power of the battery 5 and the function of generating electricity using the driving force of the engine 2. The power generated by the generator 4 is used to drive the motor 3 and charge the battery 5. A transmission mechanism (not shown) may be interposed on the power transmission path connecting the engine 2 and the generator 4.

The motor 3 is an electric motor (motor/generator) that has both the function of driving the vehicle 1 using the electric power of the battery 5 and the electric power generated by the generator 4, and the function of charging the battery 5 with electric power generated by regenerative power generation. The battery 5 is, for example, a secondary battery such as a lithium ion secondary battery or a nickel hydride battery. A drive shaft of the motor 3 is connected to drive wheels of the vehicle 1. A transmission mechanism (not shown) may be interposed on the power transmission path connecting the motor 3 and the drive wheels.

A clutch 6 is interposed on the power transmission path connecting the engine 2 and the motor 3. The engine 2 is connected to the driving wheels via the clutch 6, and the motor 3 is arranged closer to the driving wheels than the clutch 6. Furthermore, the generator 4 is connected closer to the engine 2 than the clutch 6 is. When the clutch 6 is disengaged (released), the engine 2 and generator 4 are disconnected from the drive wheels, and the motor 3 is connected to the drive wheels. Therefore, for example, by operating only the motor 3, "EV driving (motor independent driving)" is realized. In addition to this, "series running" is realized by operating the engine 2 and causing the generator 4 to generate electricity. Series running means running with the driving force of the motor 3 while causing the generator 4 to generate electricity using the driving force of the engine 2.

On the other hand, when the clutch 6 is connected (fastened), the engine 2, motor 3, and generator 4 are connected to the drive wheels. Therefore, for example, by operating only the engine 2, "engine running (engine independent running)" is realized. In addition to this, "parallel running" is realized by driving the motor 3 and generator 4. Both the series running and parallel running described above are also called "hybrid running."

The operating states of the engine 2, motor 3, generator 4, battery 5, and clutch 6 are controlled by a control device 10. The control device 10 is a computer (electronic control unit, ECU, Electronic Control Unit) that has a function of controlling at least the operating states of the engine 2 and the generator 4. The control device 10 includes a processor (arithmetic processing unit) and a memory (storage device). The contents of control (control program) executed by the control device 10 are stored in a memory, and are executed by being read into the processor as appropriate.

An accelerator opening sensor 7, a brake opening sensor 8, and a vehicle speed sensor 9 are connected to the control device 10 of this embodiment. The accelerator opening sensor 7 is a sensor that detects parameters (accelerator opening, accelerator pedal stroke, throttle opening, etc.) corresponding to the amount of depression of the accelerator pedal. The brake opening sensor 8 is a sensor that detects parameters (brake opening, brake pedal stroke, brake fluid pressure, etc.) corresponding to the amount of depression of the brake pedal. The vehicle speed sensor 9 is a sensor that detects the traveling speed (vehicle speed) of the vehicle 1. Information detected by each of these sensors 7 to 9 is transmitted to the control device 10.

FIG. 2 is a graph illustrating a characteristic defining the relationship between the accelerator opening [%] detected by the accelerator opening sensor 7 and the driver required output [kW] set by the control device 10. The accelerator opening degree is the amount of depression of the accelerator pedal (for example, the accelerator pedal stroke, the rotation angle of the accelerator pedal with respect to the fulcrum, etc.) expressed as a percentage. Further, the driver-required output is a parameter corresponding to the magnitude of the output (in other words, horsepower, electric power, and power) that the driver requests in order to run the vehicle 1. Generally, the driver request output is set to a larger value as the accelerator opening degree becomes larger. Note that the output of the drive source of the vehicle 1 is controlled such that, for example, the larger the driver requested output or vehicle speed is, the larger the output is.

FIG. 3 is a graph illustrating the relationship between the vehicle speed [km/h] detected by the vehicle speed sensor 9 and the target rotational speed [rpm] of the engine 2. The solid line graph in FIG. 3 shows the characteristics when engine 2 is motoring (when vehicle 1 is decelerating), and the broken line graph in FIG. 3 shows the characteristics when engine 2 is firing (when vehicle 1 is accelerating). show. Motoring means running the engine 2 idly using the generator 4 (driving the engine 2 to rotate without burning the fuel mixture in the cylinder), and firing means running the engine 2 idly using the generator 4. This means that the cylinder rotates independently by supplying intake air (burning the fuel mixture in the cylinder). Firing can be performed at least in a driving mode in which the engine 2 is operating, and can be performed, for example, during series driving.

The target rotational speed of the engine 2 during motoring is set to increase as the vehicle speed increases, as shown by the solid line graph in FIG. However, in a high-speed region where the vehicle speed is equal to or higher than a predetermined vehicle speed, the target rotational speed of the engine 2 is fixed to a predetermined upper limit rotational speed. Further, the target rotational speed of the engine 2 during firing is set to a smaller value than the target rotational speed set during motoring for the same vehicle speed, as shown by the broken line graph in FIG.

If the setting of the target rotational speed as shown in FIG. 3 is strictly adhered to, the target rotational speed will inevitably decrease when the state of the engine 2 transitions from the motoring state to the firing state, and the drive feeling may deteriorate. For example, when the accelerator pedal is depressed during regenerative motoring control and the engine 2 enters a firing state, the rotational speed of the engine 2 (engine rotational speed) decreases rapidly, giving the driver a sense of discomfort. In consideration of such issues, the control device 10 of the present embodiment is configured to operate as shown in the broken line graph in FIG. Set a target rotation speed that is different from the characteristics of.

[2. Control configuration]
The control device 10 performs at least regenerative motoring control and first power generation control. Preferably, in addition to these controls, second power generation control is performed.
Regenerative motoring control means that regenerative power from the motor 3 is supplied to the generator 4 while driving and when the accelerator is off (the accelerator opening is below a predetermined opening, the driver required torque and the driver required output are below a threshold). This is a control in which the engine 2 is motored (idle running) at a predetermined target rotational speed. The conditions for implementing the regenerative motoring control include at least that the vehicle 1 is traveling and the accelerator is off. In addition, conditions such as the charging rate of the battery 5, presence or absence of battery failure, battery temperature, brake opening, braking force required of the vehicle 1, operating state of the friction brake device (not shown), and road surface condition are checked for the regenerative motor. It may be included in the ring control execution conditions.

The first power generation control is a control that is executed instead of the regenerative motoring control when the accelerator is turned on while the regenerative motoring control is being performed, and the rotational speed of the engine 2 is adjusted at that moment (when the accelerator is turned on). This control is to cause the generator 4 to generate electricity while firing the engine 2 while keeping the target rotational speed fixed at the target rotational speed at the time point). In other words, the first power generation control means that when the accelerator is turned on during regenerative motoring control, setting of the target rotation speed based on the broken line graph in FIG. 3 is suspended, and the target rotation speed at that point is It is a control that maintains the As a result, sudden changes in the noise and vibration of the engine 2 before and after the accelerator is turned on are suppressed, and the driving feeling is improved.

In the first power generation control, the torque of the engine 2 can be set to be larger as the accelerator opening (or the corresponding driver requested output) is larger. On the other hand, since the target rotational speed is fixed, the actual rotational speed of the engine 2 is maintained. The rotational speed of the engine 2 can be changed by adjusting the load of the generator 4 on the engine 2 (power that the generator 4 converts into electric power). In this way, during the first power generation control, the control device 10 can function to maintain the rotational speed of the engine 2 while increasing the torque of the engine 2 as the accelerator opening becomes larger.

The conditions for ending the first power generation control include at least that the accelerator is off (the accelerator opening is less than or equal to a predetermined opening). If this condition is satisfied, the control device 10 can terminate the first power generation control and restart the regenerative motoring control. Furthermore, the conditions for ending the first power generation control in this embodiment include that the driver requested output exceeds a predetermined value. When this condition is satisfied, the control device 10 ends the first power generation control and implements the second power generation control.

The second power generation control means that during the first power generation control, if the driver requested output exceeds a predetermined value (or if the accelerator opening exceeds a predetermined opening), the first power generation control is stopped and the rotational speed of the engine 2 is changed. This is a control that increases the In other words, the second power generation control is a control that restarts the setting of the target rotational speed based on the broken line graph in FIG. 3 when the driver depresses the accelerator pedal significantly. As a result, the noise and vibration of the engine 2 increase as the accelerator opening degree increases, and a driving feeling that is natural and easy to intuitively understand is realized. Note that the conditions for ending the second power generation control include at least that the accelerator is off. If this condition is satisfied, the control device 10 can end the second power generation control and restart the regenerative motoring control.

[3. flowchart]
FIG. 4 is a flowchart illustrating the flow of the first power generation control and the second power generation control. The control shown in this flowchart is repeatedly executed within the control device 10 at a predetermined period, for example, when the power switch of the vehicle 1 (not shown) is on and the vehicle 1 is ready to travel (in a READY state). Steps A1 to A3 mainly correspond to regenerative motoring control, steps A4 to A8 mainly correspond to first power generation control, and step A9 correspond to second power generation control.

In step A1, it is determined whether conditions for implementing regenerative motoring control are satisfied. If this condition is met, control proceeds to step A2. On the other hand, if the condition of step A1 is not satisfied, the control in this cycle ends.
In step A2, a target rotational speed of the engine 2 is set in accordance with the vehicle speed based on, for example, the characteristics shown in the solid line graph in FIG. Here, the higher the vehicle speed is, the higher the target rotational speed of the engine 2 is set. In other words, the faster the vehicle speed is, the greater the regenerative power generated by the motor 3 becomes, so the target rotational speed of the engine 2 driven by the generator 4 is set so that the generator 4 consumes an amount of power commensurate with the regenerated power. set high.

In step A3, regenerative motoring control is performed based on the target rotational speed set in step A2. That is, the regenerated power of the motor 3 is supplied to the generator 4, and the generator 4 motors the engine 2 so that the rotational speed of the engine 2 reaches the target rotational speed.
In step A4, it is determined whether the accelerator is on. Here, if it is determined that the accelerator is not on, the control in this cycle ends. From the next period onwards, the regenerative motoring control is continued as long as the conditions for implementing the regenerative motoring control are satisfied. On the other hand, if it is determined in step A4 that the accelerator is on, the control proceeds to step A5.

In step A5, the driver required output is calculated based on the accelerator opening based on the characteristics as shown in FIG. 2, for example. The larger the accelerator opening, the larger the driver request output is set. In the following step A6, it is determined whether the driver request output calculated in step A5 is less than or equal to a predetermined value. If this condition is met, control proceeds to step A7.

In step A7, the first power generation control is performed to cause the generator 4 to generate electricity while firing the engine 2 while keeping the rotational speed of the engine 2 fixed at the target rotational speed at that time. As a result, the operating state of the engine 2 shifts from the motoring state to the firing state. The torque of the engine 2 is set according to the driver's requested output. On the other hand, the target rotational speed of the engine 2 in the firing state is maintained at the same speed as the target rotational speed of the engine 2 in the motoring state. Therefore, the noise and vibration of the engine 2 hardly change, and the drive feeling is improved.

In the following step A8, it is determined whether the accelerator is off. Here, if it is determined that the accelerator is not off, the control returns to step A5 and the driver requested output is calculated again. Thereafter, the first power generation control is continued as long as the driver requested output is equal to or less than the predetermined value. Further, if it is determined in step A8 that the accelerator is off, the control in this cycle ends. From the next cycle onward, regenerative motoring control is restarted as long as the conditions for implementing regenerative motoring control are met.

If it is determined in step A6 that the driver requested output exceeds the predetermined value, control proceeds to step A9. In step A9, the second power generation control is performed instead of the first power generation control, and the rotational speed of the engine 2 is changed to a rotational speed higher than the target rotational speed at that time. The torque of the engine 2 is set according to the driver's requested output. During the second power generation control, the output of the engine 2 becomes larger than during the first power generation control, and the power generated by the generator 4 also increases.

In the following step A8, it is determined whether the accelerator is off. Here, if it is determined that the accelerator is not off, the control returns to step A5 and the driver requested output is calculated again. Thereafter, the second power generation control is continued as long as the driver requested output exceeds the predetermined value. Further, if it is determined in step A8 that the accelerator is off, the control in this cycle ends. From the next cycle onward, regenerative motoring control is restarted as long as the conditions for implementing regenerative motoring control are met.

[4. Effect】
FIG. 5 is a time chart illustrating the effects of the first power generation control and the second power generation control. Here, it is assumed that regenerative motoring control has been performed before time _t1 and the accelerator is off. When the accelerator pedal is slightly depressed to turn on the accelerator at time _t1 , the regenerative motoring control is stopped and the first power generation control is started. The state of the engine 2 transitions from a motoring state to a firing state at time _t1 . On the other hand, in the first power generation control, the target rotational speed of the engine 2 is maintained at the target rotational speed before time _t1 , and the actual rotational speed of the engine 2 also becomes a constant value. Therefore, the noise and vibration of the engine 2 hardly change, and the drive feeling is improved.

Note that if the first power generation control is not performed, the target rotational speed of the engine 2 at time _t1 may be set to a relatively low value, so the actual rotational speed of the engine 2 may be changed as shown by the broken line in FIG. It will drop to . However, in this embodiment, since the first power generation control is performed, the rotational speed of the engine 2 does not substantially change and remains constant before and after time _t1 . Furthermore, when the first power generation control is not performed, the torque of the engine 2 may reach a somewhat large value, as shown by the two-dot chain line in FIG.

On the other hand, in this embodiment, the rotational speed of the engine 2 is higher than when the first power generation control is not performed, so the torque value for the same output (power) is smaller. Therefore, by reducing the torque by the amount that the rotational speed of the engine 2 has increased compared to the case where the first power generation control is not performed (in other words, so that the product of the rotational speed and the torque is constant), the generator It becomes possible to maintain the rotational speed of the engine 2 without changing the generated power of the engine 4. Further, the output of the battery 5 (power extracted from the battery 5) is equal to the power consumption of the motor 3 and various auxiliary machines minus the power generated by the generator 4.

When the accelerator pedal is pressed back and the accelerator is turned off at time _t2 , the first power generation control is stopped and the regenerative motoring control is restarted. The state of the engine 2 transitions from the firing state to the motoring state at time _t2 . On the other hand, the target rotational speed of the engine 2 is kept constant even after time _t2 , and the actual rotational speed also remains constant. Therefore, the noise and vibration of the engine 2 hardly change, and the drive feeling is improved.

When the accelerator pedal is depressed again at time _t3 and the accelerator is turned on, the regenerative motoring control is stopped and the first power generation control is restarted. The state of the engine 2 transitions from the motoring state to the firing state at time _t3 . On the other hand, the target rotational speed of the engine 2 is kept constant even after time _t3 , and the actual rotational speed also remains constant. Therefore, the noise and vibration of the engine 2 hardly change, and the drive feeling is improved.

When further depression of the accelerator pedal is started at time _t4 , the torque of the engine 2 is set to be greater as the accelerator opening degree is greater. On the other hand, since the target rotational speed of the engine 2 is kept constant even after time _t4 , the output of the engine 2 (the product of rotational speed and torque) increases as the torque increases, and the power generated by the generator 4 also gradually increases. increases to Thereafter, when the driver requested output exceeds a predetermined value at time _t5 , second power generation control is performed instead of first power generation control. In the second power generation control, setting of the target rotation speed based on the broken line graph in FIG. 3 is restarted. As a result, the rotational speed of the engine 2 increases, and the torque of the engine 2 and the power generated by the generator 4 also increase. Therefore, as the accelerator opening degree increases, the noise and vibration of the engine 2 increase, and a natural and intuitively understandable drive feeling is realized.

FIG. 6 is a graph illustrating the output characteristics (relationship between rotational speed and torque) of the engine 2. The thick solid line in FIG. 6 shows the relationship between the rotational speed of the engine 2 and the maximum torque. The thin solid lines in FIG. 6 are curves connecting operating points at which the same thermal efficiency (fuel efficiency) can be obtained at fixed thermal efficiency intervals, and are contour lines regarding the level of thermal efficiency. The operating point P ₀ in FIG. 6 is the operating point of the engine 2 when the first power generation control is not performed at times t ₁ to t ₂ and times t ₃ to t ₄ in FIG. 5, and the operating point P ₁ is This is the operating point of the engine 2 when the first power generation control is performed at times t ₁ to t ₂ and times t ₃ to t ₄ in FIG. 5 .

The operating point _P1 is set so that the output (product of rotational speed and torque) at the operating point _P1 is the same as the output at the operating point _P0 . Therefore, the power generated by the generator 4 does not need to be changed depending on whether the first power generation control is performed or not. Furthermore, the thermal efficiency at the operating point _P1 is slightly lower than that at the operating point _P0 . From this, it can be seen that implementing the first power generation control is slightly more disadvantageous in terms of fuel efficiency than not implementing the first power generation control.

Further, the operating point P ₂ in FIG. 6 is the operating point of the engine 2 when the torque is increased while the rotational speed of the engine 2 is fixed from time t ₄ to t ₅ in FIG. 5, and the operating point P ₃ is an operating point of the engine 2 in the second power generation control after time t5 in FIG. ₅ , and is an operating point located near the maximum torque of the engine 2, for example. Operating point _P2 has a slightly higher thermal efficiency than operating point _P1 . From this, it can be seen that in the first power generation control, the disadvantage in terms of fuel consumption decreases as the accelerator opening degree increases. Furthermore, since the operating point _P3 is located to the upper right of the operating point _P2 in FIG. 6, it can be seen that the output (the product of rotational speed and torque) is increasing.

[5. effect]
(1) The hybrid vehicle 1 of this embodiment includes an engine 2, a motor 3 that drives wheels and performs regenerative braking, a generator 4 that generates electricity using the driving force of the engine 2 and drives the engine 2, and a motor 3 and a generator that drive the engine 2. 4 and a battery 5 connected to the battery 5. The vehicle also includes a control device 10 that performs regenerative motoring control that supplies regenerative power from the motor 3 to the generator 4 and motors the engine 2 at a predetermined target rotational speed when the vehicle is running and the accelerator is off. When the accelerator is turned on while the regenerative motoring control is being performed, the control device 10 stops the regenerative motoring control and performs the first power generation control. The first power generation control is control that causes the generator 4 to generate electricity while firing the engine 2 while keeping the rotational speed of the engine 2 fixed at the target rotational speed at that time.

By implementing such control, fluctuations in the rotational speed of the engine 2 can be suppressed in the transition process from regenerative motoring control to first power generation control. In other words, when transitioning from the motoring state to the firing state, the target rotational speed of the engine 2 in the firing state can be made the same as the target rotational speed of the engine 2 in the motoring state. Changes in noise and vibration can be suppressed. Therefore, the drive feeling during acceleration from regenerative motoring control can be improved.

Note that the initial value of the torque of the engine 2 in the first power generation control (torque T ₁ at the operating point P ₁ in FIG. 6) is set so that the output at the operating point P ₁ is the same as the output at the operating point P ₀ . be done. With such a setting, the output of the engine 2 can be made the same as the existing control, and the power generated by the generator 4 can also be made the same.

(2) In the first power generation control, the control device 10 described above can perform control to maintain the rotational speed of the engine 2 while increasing the torque of the engine 2 as the accelerator opening is larger. For example, a driver requested output is set based on the characteristics shown in FIG. 2, and the torque of the engine 2 is controlled based on this driver requested output. With such control, it is possible to increase the output of the engine 2 while suppressing changes in noise and vibration of the engine 2, and it is possible to improve the drive feeling during acceleration from regenerative motoring control. Furthermore, by increasing the output of the engine 2, the amount of power generated by the generator 4 can be increased. Therefore, the electric power for driving the motor 3 can be increased, and a good feeling of acceleration can be achieved.

(3) During the first power generation control, the control device 10 described above can perform a second power generation control in which the first power generation control is stopped and the rotational speed of the engine 2 is increased when the driver requested output exceeds a predetermined value. . For example, when the driver required output increases as after time _t5 in FIG. 5, by increasing the rotational speed of the engine 2 within a range equal to or higher than the target rotational speed, it is possible to realize a behavior of the engine 2 that does not cause any discomfort. , can improve drive feeling. Further, by increasing the power generated by the generator 4, the acceleration performance of the vehicle 1 can be improved, and the driving feeling can be improved.

(4) The above control device 10 can restart regenerative motoring control when the accelerator is turned off during execution of first power generation control. With such control, regenerative motoring control can be restarted without changing the noise or vibration of the engine 2 when transitioning from the firing state to the motoring state. Therefore, the drive feeling after the first power generation control can be improved.

[6. others]
The above-described embodiments are merely illustrative, and there is no intention to exclude the application of various modifications and techniques not specified in the present embodiments. Each configuration of this embodiment can be modified and implemented in various ways without departing from the spirit thereof. Further, each configuration of this embodiment can be selected or combined as necessary, or can be combined as appropriate.

For example, in the above embodiment, the control device 10 that performs regenerative motoring control, first power generation control, and second power generation control is illustrated, but the second power generation control can be omitted. Further, in the above embodiment, when the accelerator is turned off during execution of the first power generation control, the regenerative motoring control is restarted, but such control is not essential. Further, the torque of the engine 2 in the first power generation control may be set according to the accelerator opening degree, may be set based on other parameters, or may be set to a preset fixed value. At least, by shifting the regenerative motoring control to the first power generation control while fixing the rotational speed of the engine 2 to the current target rotational speed, the same effects as in the above embodiment can be obtained.

The present invention can be used in the manufacturing industry of hybrid vehicles, and can also be used in the manufacturing industry of control devices for hybrid vehicles.

1 Vehicle (hybrid vehicle)
2 Engine 3 Motor 4 Generator 5 Battery 6 Clutch 7 Accelerator opening sensor 8 Brake opening sensor 9 Vehicle speed sensor 10 Control device

Claims

engine and
A motor that drives the wheels and performs regenerative braking;
a generator that generates electricity using the driving force of the engine and drives the engine;
a battery connected to the motor and the generator;
a control device that performs regenerative motoring control that supplies regenerative power of the motor to the generator while the vehicle is running and the accelerator is off, and motors the engine at a predetermined target rotational speed;
The control device stops the regenerative motoring control when the accelerator is turned on while performing the regenerative motoring control, and fires the engine while fixing the engine rotational speed to the target rotational speed at that time. A hybrid vehicle characterized in that a first power generation control is performed in which the generator is caused to generate electricity while performing the first power generation control.
2. The hybrid vehicle according to claim 1, wherein the control device maintains the engine rotation speed while increasing the torque of the engine as the accelerator opening becomes larger during the first power generation control.
The control device is characterized in that, during the first power generation control, if the driver requested output exceeds a predetermined value, the first power generation control is stopped and the second power generation control is performed to increase the engine rotation speed. , A hybrid vehicle according to claim 1 or 2.
The control device according to any one of claims 1 to 3, wherein the control device restarts the regenerative motoring control when the accelerator is turned off during the execution of the first power generation control. hybrid vehicle.