JP7263801B2 - Hybrid vehicle control device - Google Patents

Description

The present invention relates to a hybrid vehicle control device.

Patent Document 1 discloses a motor generator connected to an input shaft of a manual transmission via a first clutch that operates when a clutch pedal is depressed, and a rotor shaft of the motor generator connected via a second clutch. A hybrid vehicle with an internal combustion engine is disclosed.

This hybrid vehicle controls the motor generator so that power is output from the motor generator when the first clutch is in the engaged state, the second clutch is in the disengaged state, and the accelerator pedal is depressed. It has a controller. When the speed of the hybrid vehicle is higher than a predetermined judgment speed, the control device executes low-speed travel control to control the motor generator so that power is output from the motor generator even when the accelerator pedal is not depressed. According to the control device for a hybrid vehicle described in Patent Document 1, when the vehicle is driven at a low speed for a long time after starting in a traffic jam, the driver does not need to keep depressing the accelerator pedal. It is possible to reduce the burden on the driver.

JP 2013-216152 A

However, in the hybrid vehicle disclosed in Patent Literature 1, when the vehicle speed becomes equal to or lower than a predetermined determination speed during execution of low-speed travel control in the EV travel mode, low-speed travel control is stopped. When the low-speed travel control is stopped during the EV travel mode, power is not output from the motor generator and the second clutch is released, so the load applied to the drive wheels from the transmission side is reduced. , the vehicle may move unintentionally by the driver.

For example, during the EV driving mode and during execution of the low-speed driving control, when the driving road is switched from a flat road to an uphill road and the vehicle speed becomes a predetermined judgment speed or less and the low-speed driving control is stopped, the driver unintentional rolling of the vehicle may occur.

Further, as in the hybrid vehicle described in Patent Document 1, if the driving operation by the driver at the time of starting the vehicle differs between the EV driving mode and the engine driving mode, the driver can select which driving mode for each driving mode. There is a possibility of confusion as to whether the operation should be performed.

The present invention has been made in view of the circumstances as described above, and provides a hybrid vehicle that can prevent the driver from confusing driving operations regardless of the driving mode while suppressing unintended movement of the vehicle by the driver. The object is to provide a control device.

In order to achieve the above object, the present invention provides a control device for a hybrid vehicle in which an engine and a motor are connected via an automatic clutch, and the motor and a transmission are connected via a manual clutch, the hybrid vehicle comprising: As vehicle running modes, an EV mode in which the automatic clutch is released and the vehicle runs by the power of the motor, and an HEV mode in which the automatic clutch is engaged and the vehicle runs by the power of the engine or the engine and the motor. a controller for outputting power of the motor when the rotational speed of the motor is higher than a predetermined rotational speed with the manual clutch engaged and an accelerator pedal is depressed; has a configuration in which the automatic clutch is engaged when the rotational speed of the motor is equal to or lower than the predetermined rotational speed during the EV mode, and the load of the engine at rest is applied to the driving wheels .

Advantageous Effects of Invention According to the present invention, it is possible to provide a control device for a hybrid vehicle that can prevent the driver from confusing driving operations regardless of the driving mode while suppressing movement of the vehicle that is not intended by the driver.

FIG. 1 is a schematic configuration diagram of a hybrid vehicle according to one embodiment of the present invention. FIG. 2 is a flow chart showing the flow of automatic clutch switching control processing executed by the ECU installed in the hybrid vehicle according to one embodiment of the present invention. FIG. 3 is a time chart showing an example of a case in which the vehicle is in the EV mode of the hybrid vehicle according to the embodiment of the present invention, and the vehicle is subjected to the downhill control.

A control device for a hybrid vehicle according to an embodiment of the present invention is a control device for a hybrid vehicle in which an engine and a motor are connected via an automatic clutch, and a motor and a transmission are connected via a manual clutch. , as driving modes of the hybrid vehicle, there are an EV mode in which the clutch is automatically released and the vehicle is driven by the power of the motor, and an HEV mode in which the automatic clutch is engaged and the vehicle is driven by the power of the engine or the engine and the motor, A controller is provided for outputting power of the motor when the rotational speed of the motor is higher than a predetermined rotational speed with the manual clutch engaged and the accelerator pedal is depressed. is equal to or lower than a predetermined rotational speed, the automatic clutch is engaged. As a result, the hybrid vehicle control apparatus according to the embodiment of the present invention can prevent the driver from confusing driving operations regardless of the driving mode while suppressing movement of the vehicle unintended by the driver.

A hybrid vehicle equipped with a control device according to an embodiment of the present invention will be described below with reference to the drawings.

As shown in FIG. 1, the hybrid vehicle 1 according to the present embodiment includes an engine 2, a motor generator 3 as a motor, a manual transmission 4 as a transmission, a differential 5, and a drive shaft 60. It includes a wheel 6 and an ECU (Electric Control Unit) 10 as a control section.

A plurality of cylinders are formed in the engine 2 . In this embodiment, the engine 2 is constructed so that each cylinder performs a series of four strokes consisting of an intake stroke, a compression stroke, an expansion stroke and an exhaust stroke.

The motor generator 3 has a function as an electric motor driven by electric power supplied from the battery 31 via the inverter 30 and a function as a generator that generates power by reverse driving force input from the manual transmission 4 . The motor generator 3 is provided with a rotation speed sensor 33 that detects the rotation speed of the motor generator 3 (hereinafter referred to as “MG rotation speed”). The rotation speed sensor 33 is connected to the ECU 10 and transmits the detected MG rotation speed to the ECU 10 .

Under the control of the ECU 10, the inverter 30 converts the DC power supplied from the battery 31 into three-phase AC power and supplies it to the motor generator 3, or converts the three-phase AC power generated by the motor generator 3 into DC power. to charge the battery 31. The battery 31 is composed of a secondary battery such as a lithium ion battery, for example.

The manual transmission 4 is configured by a manual transmission that outputs the rotation output from the engine 2 or the motor generator 3 or both at a gear ratio corresponding to one of a plurality of gear stages. The manual transmission 4 is connected to left and right drive shafts 60 via a differential 5 .

Gear stages that can be established by the manual transmission 4 include, for example, gear stages for running from 1st to 4th gears and reverse gears. The number of speed stages for running varies depending on the specifications of the hybrid vehicle 1, and is not limited to the first to fourth speed stages described above.

The gear stage of the manual transmission 4 is switched according to the operating position of a shift lever 40 operated by the driver. The operating position of the shift lever 40 is detected by a shift position sensor 41 . The shift position sensor 41 is connected to the ECU 10 and transmits detection results to the ECU 10 .

A neutral switch 42 is provided in the manual transmission 4 . Neutral switch 42 is connected to ECU 10 . The neutral switch 42 is for detecting that the manual transmission 4 is in a state in which none of the gear stages are established, that is, in a neutral state, and is turned on when the manual transmission 4 is in the neutral state.

An automatic clutch 7 is provided in a power transmission path between the engine 2 and the motor generator 3 . As the automatic clutch 7, for example, a friction clutch can be used. The engine 2 and motor generator 3 are connected via an automatic clutch 7 .

The automatic clutch 7 is operated by a clutch actuator 70 to switch between an engaged state in which power is transmitted between the engine 2 and the motor generator 3 and a released state in which power is not transmitted. The clutch actuator 70 is connected to the ECU 10 and controlled by the ECU 10 .

A manual clutch 8 is provided in a power transmission path between the motor generator 3 and the manual transmission 4 . Motor generator 3 and manual transmission 4 are connected via manual clutch 8 .

The manual clutch 8 is a mechanical clutch that operates in conjunction with the depression amount of a clutch pedal 80 operated by the driver. As the manual clutch 8, for example, a friction clutch can be used.

The depression amount of the clutch pedal 80 is detected by a clutch pedal sensor 81 . The clutch pedal sensor 81 is connected to the ECU 10 and transmits to the ECU 10 a signal corresponding to the depression amount of the clutch pedal 80 .

The hybrid vehicle 1 has an accelerator pedal 90 operated by the driver. The depression amount of the accelerator pedal 90 is detected by an accelerator opening sensor 91 . The accelerator opening sensor 91 is connected to the ECU 10 , detects the depression amount of the accelerator pedal 90 as an accelerator opening, and transmits a signal corresponding to the accelerator opening to the ECU 10 .

The ECU 10 is a computer having a CPU (Central Processing Unit), a RAM (Random Access Memory), a ROM (Read Only Memory), a flash memory for storing backup data, an input port, and an output port. made up of units.

The ROM of the computer unit stores a program for causing the computer unit to function as the ECU 10 along with various constants, various maps, and the like. That is, the computer unit functions as the ECU 10 in this embodiment by the CPU executing a program stored in the ROM using the RAM as a work area.

A vehicle speed sensor 11 and an EV mode switch 12 are connected to the ECU 10 in addition to the sensors described above. The vehicle speed sensor 11 detects the vehicle speed of the hybrid vehicle 1 and transmits the detection result to the ECU 10 . The EV mode switch 12 is a switch that sets the driving mode to the EV mode, which will be described later, when turned on by the passenger's operation.

The ECU 10 switches the running modes of the hybrid vehicle 1 . An EV mode and an HEV mode are set as the running modes in this embodiment.

The EV mode is a driving mode in which the automatic clutch 7 is released and the hybrid vehicle 1 is driven by the power of the motor generator 3 . The HEV mode is a driving mode in which the automatic clutch 7 is engaged and the hybrid vehicle 1 is driven by the power of the engine 2 or the engine 2 and the motor generator 3 .

The ECU 10 switches between the EV mode and the HEV mode depending on whether or not a predetermined EV condition is satisfied. The ECU 10 sets the EV mode as the driving mode when a predetermined EV condition is satisfied.

In this embodiment, the predetermined EV condition is, for example, that the state of charge of the battery 31 (hereinafter referred to as “SOC (State of charge)”) is equal to or higher than a predetermined SOCth and that the accelerator opening detected by the accelerator opening sensor 91 is reached. is less than a predetermined degree of opening, or the EV mode switch 12 is ON. The predetermined SOCth is the lower limit of the SOC at which the hybrid vehicle 1 can be driven by the power of the motor generator 3 .

For example, the ECU 10 sets the running mode to the EV mode when the SOC is equal to or greater than a predetermined SOCth and the accelerator opening is less than the predetermined opening. Further, the ECU 10 sets the running mode to the EV mode when the EV mode switch 12 is ON regardless of the SOC or accelerator opening.

Next, with reference to FIG. 2, processing of automatic clutch switching control executed by the ECU 10 according to this embodiment will be described. The automatic clutch switching control shown in FIG. 2 is repeatedly executed at predetermined time intervals while the hybrid vehicle 1 is running.

As shown in FIG. 2 , the ECU 10 determines whether or not the flag for executing the vehicle-skid control is ON (step S1). The trailing control implementation flag is a flag that is turned ON when the trailing control, which will be described later, is being implemented.

When the ECU 10 determines that the vehicle-skid-down control execution flag is not ON, the ECU 10 determines whether or not the predetermined EV condition described above is satisfied (step S2). When the ECU 10 determines that the predetermined EV condition is not satisfied, the ECU 10 engages the automatic clutch 7 (step S7) and terminates the automatic clutch switching control.

When the ECU 10 determines that the predetermined EV condition is satisfied in step S2, the ECU 10 releases the automatic clutch 7 (step S3). As a result, the power transmission path between the engine 2 and the motor generator 3 is cut off, and the running mode of the hybrid vehicle 1 is set to the EV mode.

Next, the ECU 10 determines whether the hybrid vehicle 1 is in the process of starting (step S4). In this embodiment, the transition to start means that the MG rotation speed is at a predetermined speed corresponding to the idling rotation speed of the engine 2 after the manual clutch 8 changes from the engaged state to the disengaged state while the hybrid vehicle 1 is stopped. It refers to the period until the rotation speed reaches MG_idle as the rotation speed. Based on the detection result of the clutch pedal sensor 81 and the MG rotation speed detected by the rotation speed sensor 33, the ECU 10 determines whether the hybrid vehicle 1 is in the process of starting or not.

When the ECU 10 determines in step S4 that the hybrid vehicle 1 is in the process of starting, the ECU 10 ends the automatic clutch switching control.

When the ECU 10 determines in step S4 that the hybrid vehicle 1 is not in the process of starting, it determines whether or not the MG rotation speed is equal to or lower than the MG_idle rotation speed (step S5). The MG_idle rotation speed is a rotation speed corresponding to the idle rotation speed of the engine 2 as described above.

When the ECU 10 determines in step S5 that the MG rotational speed is not equal to or lower than the MG_idle rotational speed, the ECU 10 ends the automatic clutch switching control. If the MG rotational speed is not equal to or lower than the MG_idle rotational speed, the hybrid vehicle 1 is not traveling at a speed that is not extremely low just before stopping in the EV mode.

When the ECU 10 determines in step S5 that the MG rotation speed is equal to or lower than the MG_idle rotation speed, the ECU 10 carries out a slip-down control that engages the automatic clutch 7 (step S6). In this step S6, the ECU 10 turns on the slipping control execution flag and ends the automatic clutch switching control.

The sliding down control in step S6 engages the automatic clutch 7 in order to apply a load such as a pumping loss as a load of the engine 2 to the drive shaft 60 when the MG rotation speed is equal to or lower than the MG_idle rotation speed. be. As a result, the load of the engine 2 is applied to the drive shaft 60 during the drift control, and the load acts as a braking force to suppress the movement of the hybrid vehicle 1 unintended by the driver.

For example, when the vehicle speed decreases on an uphill road to a vehicle speed just before stopping, the above-described skid-down control is performed to suppress the hybrid vehicle 1 from skidding unintended by the driver. Further, even if the hybrid vehicle 1 rolls down during the execution of the above-described riding control, the speed increase of the rolling down is suppressed.

Furthermore, since the load of the engine 2 also acts on the motor generator 3 during the execution of the drift control, the MG rotational speed decreases more than before the drift control is implemented, causing a pseudo engine stall. It can be felt by the driver.

It should be noted that when the sliding control is performed in step S6, the fuel injection and ignition to the engine 2 are stopped because the EV mode is in progress.

When the ECU 10 determines in step S<b>1 that the slipping control execution flag is ON, it determines whether or not a condition for canceling the slipping control is satisfied (step S<b>8 ). The condition for canceling the sliding control is satisfied when the neutral switch 42 is ON and the clutch pedal 80 is depressed, that is, when the manual clutch 8 is in the released state.

When the ECU 10 determines in step S8 that the condition for canceling the control of slipping is not satisfied, the ECU 10 ends the automatic clutch switching control. As a result, the slippage control is continued.

If the ECU 10 determines in step S8 that the condition for canceling the slipping control is satisfied, the ECU 10 turns off the slipping control execution flag (step S9), and terminates the automatic clutch switching control. As a result, in step S1 of the automatic clutch switching control for the next period, the ECU 10 determines that the drift control execution flag is not ON.

Therefore, after the automatic clutch 7 is engaged in step S6, the manual transmission 4 is in the neutral state, the clutch pedal 80 is depressed, and the condition for canceling the slip-down control is satisfied in step S8. When the conditions are satisfied, the automatic clutch 7 is released.

Next, with reference to the time chart of FIG. 3, an example of a case in which the vehicle rides down control is performed during the EV mode will be described.

As shown in FIG. 3, when the manual clutch 8 changes from the engaged state to the disengaged state at time t0 while the hybrid vehicle 1 is stopped, the hybrid vehicle 1 is in the process of starting. After that, the hybrid vehicle 1 is maintained during the start transition until time t1 when the MG rotation speed reaches the MG_idle rotation speed. The automatic clutch 7 has been released since time t0.

During the start transition of the hybrid vehicle 1, the MG rotational speed increases as the torque of the motor generator 3 (hereinafter referred to as “MG torque”) increases in response to an increase in the depression amount of the accelerator pedal 90, for example.

After that, at time t1, when the MG rotation speed reaches the MG_idle rotation speed, the start transition state ends. The automatic clutch 7 is maintained in the released state even after time t1.

After time t1, when the manual clutch 8 is switched from the disengaged state to the engaged state via the half-clutch state, the power of the motor generator 3 is output to the manual transmission 4, that is, the MG torque is transmitted to the drive shaft 60, and the vehicle speed increases. Rise. After time t1, the hybrid vehicle 1 is driven by the motive power of the motor generator 3 and is in an EV running state.

After that, when the MG torque is not increased even though the hybrid vehicle 1 moves from the flat road to the uphill road, the load applied to the output shaft of the motor generator 3 increases and the MG rotation speed decreases. . As a result, the vehicle speed also decreases.

Thereafter, when the accelerator pedal 90 is released and the MG rotation speed becomes equal to or lower than the MG_idle rotation speed at time t2 during EV running, the driving of the motor generator 3 is stopped. At this time, along with stopping the driving of the motor generator 3, the automatic clutch 7 is engaged by carrying out the slipping control. During the execution of the slipping control, the manual transmission 4 is in a gear position for running. Thereby, the load of the engine 2 is applied to the drive shaft 60 . Therefore, the load of the engine 2 acts as a braking force, and movement of the hybrid vehicle 1 not intended by the driver is suppressed. Further, when the hybrid vehicle 1 slides down, the increase in the speed of the slide down is suppressed.

As described above, the control device for a hybrid vehicle according to the present embodiment performs the slip-down control and engages the automatic clutch 7 when the MG rotation speed is equal to or lower than the MG_idle rotation speed during the EV mode. The load of the engine 2 can be applied to the drive shaft 60 when the MG rotation speed drops below the MG_idle rotation speed during the mode. As a result, the load of the engine 2 acts as a braking force, and movement of the hybrid vehicle 1 not intended by the driver can be suppressed.

Further, as described above, the hybrid vehicle control apparatus according to the present embodiment engages the automatic clutch 7 when the MG rotation speed drops below the MG_idle rotation speed during the EV mode. The braking force can be generated by the load of the engine 2 without generating the braking force by . As a result, there is no need for the motor generator 3 to generate a braking force when the hybrid vehicle 1 is stopped. Therefore, when the vehicle is stopped, the motor generator 3 is deteriorated at an early stage by generating a lock current that leads to an increase in the motor temperature. You can prevent it from happening.

Furthermore, the hybrid vehicle control apparatus according to the present embodiment generates braking force by the load of the engine 2 even when the SOC of the battery 31 is low and the motor generator 3 cannot generate the braking force. can be made Therefore, the hybrid vehicle control apparatus according to the present embodiment can generate braking force without depending on the states of the battery 31 and the motor generator 3 .

In addition, the hybrid vehicle control apparatus according to the present embodiment can make the driver feel a pseudo engine stall by performing the control of rolling downhill, and the behavior of the vehicle during EV running and during engine running can be significantly different. can be prevented. As a result, the driver can be prompted to perform the same driving operation, for example, the start operation after the engine stalls, during EV running and engine running. As a result, the hybrid vehicle control apparatus according to the present embodiment can prevent the driver from confusing driving operations regardless of the driving mode.

Furthermore, the hybrid vehicle control apparatus according to the present embodiment can prevent the vehicle behavior from greatly differing between EV running and engine running as described above, so the vehicle behavior changes between EV running and engine running. This can prevent the driver from getting confused. Therefore, the driver can drive the vehicle with the same feeling as during engine running even during EV running.

Although embodiments of the present invention have been disclosed, it will be apparent that modifications may be made by those skilled in the art without departing from the scope of the invention. All such modifications and equivalents are intended to be included in the following claims.

1 hybrid vehicle 2 engine 3 motor generator (motor)
4 Manual transmission
6 drive wheel 7 automatic clutch 8 manual clutch 10 ECU (control unit)
11 vehicle speed sensor 12 EV mode switch 31 battery 33 rotation speed sensor 40 shift lever 41 shift position sensor 42 neutral switch 60 drive shaft 80 clutch pedal 81 clutch pedal sensor 90 accelerator pedal 91 accelerator opening sensor

Claims (4)

A control device for a hybrid vehicle in which an engine and a motor are connected via an automatic clutch, and the motor and a transmission are connected via a manual clutch,
As driving modes of the hybrid vehicle, an EV mode in which the automatic clutch is released and the vehicle is driven by the power of the motor, and an HEV mode in which the automatic clutch is engaged and the vehicle is driven by the power of the engine or the engine and the motor. and
a control unit that outputs power of the motor when the rotational speed of the motor is higher than a predetermined rotational speed with the manual clutch engaged and an accelerator pedal is depressed;
When the rotation speed of the motor is equal to or lower than the predetermined rotation speed during the EV mode , the control unit engages the automatic clutch to apply the load of the stopped engine to the driving wheels. A hybrid vehicle control device characterized by: After engaging the automatic clutch during the EV mode, the control unit releases the automatic clutch when the transmission is in a neutral state, the manual clutch is released, and a predetermined EV condition is satisfied. The hybrid vehicle control device according to claim 1, characterized in that: An EV mode switch that permits the EV mode,
The predetermined EV condition is that at least the state of charge of the battery that supplies electric power to the motor is such that the vehicle can travel with the power of the motor and the amount of accelerator operation is less than a predetermined amount, or the EV mode. 3. The control device for a hybrid vehicle according to claim 2, wherein the switch is in an ON state. 4. The control device for a hybrid vehicle according to any one of claims 1 to 3, wherein the predetermined rotation speed is a rotation speed corresponding to an idle rotation speed of the engine.

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