JP7697277B2 - Hybrid vehicle control device - Google Patents

Description

The present invention relates to a control device for a hybrid vehicle.

Hybrid vehicles may execute driving assistance control to drive according to a driving plan that assigns either EV driving mode or hybrid driving mode to each section of the planned route from the current location to the destination. Technology has been developed to interrupt driving assistance control by switching the driving mode during driving assistance control (see, for example, Patent Document 1).

JP 2020-0066375 A

The driving mode after the switching operation is determined according to the current driving mode. For this reason, it is difficult for the user to know whether the driving support control has ended or not. Therefore, the present invention aims to provide a control device for a hybrid vehicle that can improve user convenience.

The above object is to provide a control device for a hybrid vehicle which is equipped with an engine, a motor, and a battery, and has a CD (Charge Depleting) mode, a CS (Charge Sustaining) mode, and a CI (Charge Increasing) mode as driving modes, the CD mode including an EV priority mode and an EV auto mode, the EV priority mode being a driving mode in which EV driving, which is electric driving using the motor, is given priority and in which driving force is limited compared to the EV auto mode, the control device is provided with a driving assistance unit which assists driving of the hybrid vehicle, a switching unit which is operable by a passenger of the hybrid vehicle and switches the driving modes , and a control unit which controls the driving modes in response to operation of the switching unit, the switching unit including a first switching unit for switching between the CD mode and the CS mode, a second switching unit for switching between the EV priority mode and the EV auto mode, This can be achieved by a control device for a hybrid vehicle including a driving plan in which the EV auto mode and the CS mode of the CD mode are assigned to each driving section of a planned driving route from a current location to a destination, a second switching unit for switching the mode to the CI mode, and a third switching unit for switching the mode to the CI mode, wherein the driving support unit executes driving support control to drive according to a driving plan in which either the EV auto mode or the CS mode of the CD mode is assigned to each driving section of a planned driving route from a current location to a destination, and when the first switching unit or the second switching unit is operated during execution of the driving support control, the control unit terminates the driving support control and switches the driving mode to the EV priority mode, and when the third switching unit is operated during execution of the driving support control, the control unit terminates the driving support control and switches the driving mode to the CI mode .

The present invention provides a hybrid vehicle control device that can improve user convenience.

FIG. 1 is a block diagram illustrating the configuration of a hybrid vehicle. FIG. 2 is a flowchart that is executed when the switching unit is operated during driving support control.

[General configuration of hybrid vehicle]
Fig. 1 is a block diagram illustrating a configuration of a hybrid vehicle 20. As shown in Fig. 1, the hybrid vehicle 20 according to this embodiment includes an engine EG and a motor MG as power sources. The hybrid vehicle 20 has a CD mode (Charge Depleting mode), a CS mode (Charge Sustaining mode), and a CI (Charge Increasing) mode as driving modes. The hybrid vehicle 20 runs by switching the driving mode automatically or in response to a user operation.

In CD mode, electric driving (EV driving) is prioritized so as to reduce the state of charge (SOC) of the battery 40. CD mode includes an EV priority mode (first mode) and an EV auto mode (second mode), and these can be switched between. In EV priority mode, the driving force is limited more than in EV auto mode, the engine is not operated as much as possible, and EV driving is prioritized. In EV auto mode, the engine is operated to output a larger driving force than in EV priority mode.

On the other hand, in the CS mode, electric driving and hybrid driving are used in combination to maintain the storage ratio SOC of the battery 40 at a target ratio. Electric driving is a mode in which the vehicle runs only on power from the motor MG with the engine EG stopped, and hybrid driving is a mode in which the engine EG is operated and the vehicle runs on power from the engine EG and power from the motor MG.

In the CD mode, the hybrid vehicle 20 is controlled to run in EV mode by consuming the power storage rate SOC rather than maintaining the power storage rate SOC of the battery 40. Therefore, in the CD mode, the power storage rate SOC gradually decreases as the travel distance of the hybrid vehicle 20 increases. In contrast, in the CS mode, the hybrid vehicle 20 is controlled to run in EV mode so that maintaining the power storage rate SOC is prioritized over maintaining the power storage rate SOC.

The CI mode is a driving mode in which the battery 40 is charged and the SOC is restored. The target value of the SOC is set to a predetermined value, such as a fully charged state. The vehicle is driven by the engine, power is generated by the motor MG, the battery 40 is charged, and the SOC is increased to the target value.

The hybrid vehicle 20 shown in FIG. 1 includes, in addition to a power source, an ECU 50, an ignition switch 21, a GPS (Global Positioning System, Global Positioning Satellite) 22, an onboard camera 24, a millimeter wave radar 26, an acceleration sensor 28, a speed sensor 30, an accelerator sensor 32, a brake sensor 34, a switching unit 31, a battery actuator 38, a battery 40, a hybrid electronic control unit (hereinafter referred to as hybrid ECU) 52, an accelerator actuator 60, a brake actuator 62, a brake device 64, a display device 66, a meter 68, a communication device 70, a navigation system 80, and the like.

The ECU 50 is configured as, for example, a microcomputer, and includes an arithmetic unit such as a CPU (Central Processing Unit), storage devices such as a RAM (Random Access Memory), a ROM (Read Only Memory) and a flash memory, input ports, output ports, communication ports, etc. The ECU 50 functions as a control unit for driving assistance control and for switching driving modes in response to the user's operation of the switching unit 31.

The ECU 50 includes a driving assistance unit 51 as a functional block. When a route from the current location to the destination is set by the navigation system 80 and driving assistance control can be performed, the driving assistance unit 51 performs driving assistance by assigning either the EV auto mode or the CS mode of the CD mode to the driving mode of each section of the route.

In cruise assist control, the driving mode is either EV auto mode or CS mode. On the other hand, EV priority mode in CD mode and CI mode are driving modes other than the driving modes set in cruise assist control. In other words, when the driving mode is EV priority mode or CI mode, cruise assist control is not being performed.

The engine EG is configured as, for example, an internal combustion engine. The motor MG is configured as, for example, an electric motor that also functions as a generator, such as a synchronous motor. The motor MG is connected to the battery 40 via an inverter (not shown), and can output driving force using power supplied from the battery 40 and charge the battery 40 with the generated power.

The GPS 22 is a device that detects the position of the vehicle based on signals transmitted from multiple GPS satellites. The onboard camera 24 is a camera that captures images of the surroundings of the vehicle, and includes, for example, a front camera that captures images in front of the vehicle and a rear camera that captures images behind the vehicle. The millimeter wave radar 26 detects the distance and relative speed between the host vehicle and the vehicle in front, and also detects the distance and relative speed between the host vehicle and the vehicle in front.

The acceleration sensor 28 detects, for example, the acceleration in the forward/rearward direction and the left/right direction (lateral direction) of the vehicle. The speed sensor 30 detects the vehicle speed based on the wheel speed and other factors. The accelerator sensor 32 detects the accelerator opening according to the amount of depression of the accelerator pedal by the driver. The brake sensor 34 detects the brake position as the amount of depression of the brake pedal by the driver.

In driving assistance control, the driving mode is automatically switched. On the other hand, when the user intentionally switches the driving mode, the user only needs to operate the switching unit 31. When the switching unit 31 is operated during driving assistance control, the driving assistance control ends, and the user switches the driving mode using the switching unit 31.

The switching unit 31 includes a CD/CS switch 35 (first switching unit), an EV auto/EV priority switch 36 (second switching unit), and a CI switch 37 (third switching unit). The CD/CS switch 35 is located, for example, near the steering wheel of the driver's seat, and is a switch for switching between the CD mode and the CS mode. The EV auto/EV priority switch 36 is located, for example, near the steering wheel of the driver's seat, and is a switch for switching between the EV priority mode and the EV auto mode while the CD mode is being implemented.

The CI changeover switch 37 is a switch for switching the driving mode to the CI mode. The CI changeover switch 37 may be a switch independent of the CD/CS changeover switch 35 and the EV auto/EV priority changeover switch 36, for example, or may be a common switch to these switches. For example, the CI changeover switch 37 may be common to the CD/CS changeover switch 35. When the CD/CS changeover switch 35 is pressed for less than a predetermined time, switching between the CD mode and the CS mode is performed. When the CD/CS changeover switch 35 is pressed for more than a predetermined time, switching to the CI mode is performed.

The battery actuator 38 manages the battery 40 based on the state of the battery 40, such as the terminal voltage, the charge/discharge current, and the battery temperature. The battery actuator 38 calculates the battery 40's storage percentage SOC, the battery 40's maximum allowable output power, and the battery 40's maximum allowable input power. The maximum allowable output power is the upper limit (output limit) of the power output from the battery 40. The maximum allowable input power is the upper limit (input limit) of the power input to the battery 40. The battery actuator 38 calculates the battery storage percentage SOC as the ratio of the remaining storage capacity to the total storage capacity based on the charge/discharge current. The battery actuator 38 calculates the maximum allowable output power and the maximum allowable input power based on the battery storage percentage SOC, the battery temperature, and the like. The battery 40 is configured as a chargeable/dischargeable secondary battery, and may be, for example, a lithium-ion battery, a nickel-metal hydride battery, or a lead-acid battery.

The hybrid ECU 52 is configured as, for example, a microcomputer, and includes an arithmetic unit such as a CPU, storage units such as RAM, ROM and flash memory, input ports, output ports, communication ports, etc. The hybrid ECU 52 sets the driving mode, and sets the target operating point (target rotation speed and target torque) of the engine EG and the torque command of the motor MG based on the driving mode, the accelerator opening from the accelerator sensor 32, the brake position from the brake sensor 34, and the output and input limitations from the battery actuator 38.

The hybrid ECU 52 obtains the accelerator opening from the accelerator sensor 32 and the vehicle speed from the speed sensor 30. When the hybrid vehicle 20 runs on electric power, the hybrid ECU 52 sets the required driving force and required power based on the accelerator opening and the vehicle speed, sets a torque command for the motor MG so that the hybrid vehicle 20 outputs the required driving force and required power, and transmits the set torque command to the accelerator actuator 60.

When the hybrid vehicle 20 is running in hybrid mode, the hybrid ECU 52 sets a target driving point for the engine EG and a torque command for the motor MG so that the hybrid vehicle 20 outputs the required driving force and required power, and transmits the target driving point and torque command to the accelerator actuator 60. When the brake pedal is depressed, the hybrid ECU 52 sets a required braking force based on the brake position from the brake sensor 34 and the vehicle speed from the speed sensor 30, sets a torque command for regeneration to regeneratively control the motor MG based on the required braking force and the vehicle speed, and sets a target braking force by the brake device. The hybrid ECU 52 transmits the torque command to the accelerator actuator 60 and transmits the target braking force to the brake actuator 62.

The accelerator actuator 60 controls the drive of the engine EG and the motor MG according to the target driving point and torque command set by the hybrid ECU 52. The accelerator actuator 60 performs intake air volume control, fuel injection control, ignition control, intake valve opening and closing timing control, etc. so that the engine EG is operated at the target driving point (target rotation speed and target torque). The accelerator actuator 60 also performs switching control of the switching elements of the inverter for driving the motor MG so that the motor MG outputs a torque corresponding to the torque command.

The brake actuator 62 controls the brake device 64 so that the target braking force set by the hybrid ECU 52 is applied to the vehicle by the brake device 64. The brake device 64 is, for example, a hydraulically driven friction brake.

The display device 66 is, for example, built into an installation panel in front of the driver's seat, and displays various information. The display device 66 displays, for example, the currently active driving mode. The meter 68 is, for example, built into an installation panel in front of the driver's seat.

The communication device 70 transmits information about the vehicle to the traffic information management center 100 and receives road traffic information from the traffic information management center 100. The vehicle information includes, for example, the vehicle's position, vehicle speed, driving power, and driving mode. The road traffic information includes, for example, information about current and future congestion, information about the current average vehicle speed and predicted future average vehicle speed in a section of the driving route, information about traffic regulations, information about weather, and information about road surface conditions. The communication device 70 communicates with the traffic information management center 100 at predetermined intervals (for example, every 30 seconds, every minute, or every two minutes).

The navigation system 80 is a system that guides the vehicle to a specified destination, and includes a display unit 82 and a map information database 84. The navigation system 80 can communicate with the traffic information management center 100, and performs navigation in cooperation with the traffic information management center 100. In this case, when a destination is set, the navigation system 80 transmits information about the destination and information about the current location (current vehicle position) acquired by the GPS 22 to the traffic information management center 100, and receives the route set by the traffic information management center 100 in response to this transmission. The navigation system 80 then communicates with the traffic information management center 100 at predetermined intervals (for example, every 3 minutes or every 5 minutes) based on the set route to provide route guidance. The navigation system 80 can also set a route and provide route guidance without cooperating with the traffic information management center 100. In this case, when a destination is set, the navigation system 80 sets a route based on information about the destination, information about the current location, and information stored in the map information database 84.

During driving assistance control, the driving mode is automatically switched. On the other hand, when the user operates the switching unit 31, the driving assistance unit 51 ends the driving assistance control. The driving mode is switched according to the user's operation. In this embodiment, the end of driving assistance control is made easy to understand.

Figure 2 is a flowchart that is executed when the switching unit 31 is operated during driving support control. As shown in Figure 2, the ECU 50 determines whether driving support control is in progress (step S10). If the determination is negative (No), the process ends. The ECU 50 switches the driving mode in response to the operation of each switch of the switching unit 31.

If the determination is positive (Yes), the ECU 50 determines whether the CD/CS changeover switch 35 has been operated (step S12). If the determination is negative, the ECU 50 determines whether the EV auto/EV priority changeover switch 36 has been operated (step S14).

If either the CD/CS changeover switch 35 or the EV auto/EV priority changeover switch 36 is operated, one of steps S12 and S14 is determined to be positive. In this case, the ECU 50 ends the driving support control and switches the driving mode to the EV priority mode (step S16). After step S16, the process ends.

If the determination is negative in steps S12 and S14, the ECU 50 determines whether the CI changeover switch 37 has been operated (step S18). If the determination is negative, the process ends. If the determination is positive, the ECU 50 ends the driving assistance control and switches the driving mode to the CI mode (step S20). After step S20, the process ends.

Table 1 shows the driving mode when the switching unit 31 is operated during driving support control in the comparative example. During driving support control, the driving mode (current mode) is the EV auto mode or the CS mode.

In the example of Table 1, when the CD/CS changeover switch 35 is operated while driving in EV auto mode, the mode is switched from EV auto mode to CS mode. When the CD/CS changeover switch 35 is operated while driving in CS mode, the mode is switched from CS mode to EV priority mode. When the EV auto/EV priority changeover switch 36 is operated while driving in EV auto mode, the mode is switched from EV auto mode to EV priority mode. When the EV auto/EV priority changeover switch 36 is operated while driving in CS mode, the mode is switched from CS mode to EV auto mode. When the CI changeover switch 37 is operated, the mode is switched from EV auto mode and CS mode to CI mode.

In driving assistance control, switching between CS mode and EV auto mode is performed automatically. In the example of Table 1, switching to CS mode is performed by operating the CD/CS changeover switch 35 while driving in EV auto mode. Switching from CS mode to EV auto mode is performed by operating the EV auto/EV priority changeover switch 36 while driving in CS mode. These changes are the same as automatic driving mode changes in driving assistance control. Therefore, it is difficult to know whether the driving mode was changed by driving assistance control or by the user operating the changeover switch, and it is also difficult to know whether driving assistance control has ended.

Table 2 shows the driving mode when the switching unit 31 is operated during driving support control in this embodiment.

When the CD/CS changeover switch 35 is operated while driving in EV auto mode or CS mode, the mode is switched from EV auto mode and CS mode to EV priority mode. When the EV auto/EV priority changeover switch 36 is operated while driving in EV auto mode or CS mode, the mode is switched from EV auto mode and CS mode to EV priority mode. When the CI changeover switch 37 is operated, the mode is switched from EV auto mode and CS mode to CI mode.

According to this embodiment, as shown in Table 2, when the CD/CS changeover switch 35 or the EV auto/EV priority changeover switch 36 is operated during driving support control, the driving mode is switched to the EV priority mode (step S16 in FIG. 2). The EV priority mode is not a driving mode set in the driving support control. In other words, when the driving mode becomes the EV priority mode, driving support control is not being performed. When the driving mode switches to the EV priority mode, the driving support control ends, and it is clear that the driving mode has been switched by the user's operation of the switching unit 31. This improves user convenience.

In cruise assist control, the driving mode is set to either CS mode or EV auto mode. As in steps S12 and S14 in FIG. 2, when the CD/CS changeover switch 35 or the EV auto/EV priority changeover switch 36 is operated, the driving mode is switched to EV priority mode, which is a driving mode other than the driving mode assigned by the cruise assist control. When the driving mode becomes EV priority mode, the cruise assist control ends, making it easier to understand that the driving mode has been switched by the user's operation, improving convenience.

After driving assistance control ends, the user can switch from EV priority mode to CS mode by operating the CD/CS changeover switch 35. The user can switch from EV priority mode to EV auto mode by operating the EV auto/EV priority changeover switch 36. The user can select the driving mode according to their intention, improving user convenience.

The driving mode determined when the switching unit 31 is operated is not limited to the EV priority mode, and may be, for example, the CI mode as follows. When the CI changeover switch 37 is operated, the driving assistance control ends and the driving mode switches to the CI mode (step S20 in FIG. 2). The CI mode is not a driving mode set in the driving assistance control. When the driving mode becomes the CI mode, it becomes easy to understand that the driving assistance control ends and the driving mode has been switched by the user's operation of the switching unit 31. When it is desired to charge the battery 40, the CI changeover switch 37 can be operated to drive in the CI mode and charge the battery 40. The CI mode can be selected according to the user's intention, improving user convenience.

Although the embodiments of the present invention have been described in detail above, the present invention is not limited to these specific embodiments, and various modifications and variations are possible within the scope of the gist of the present invention as described in the claims.

20 Hybrid vehicle 21 Ignition switch 22 GPS
24 In-vehicle camera 26 Millimeter wave radar 28 Acceleration sensor 30 Speed sensor 31 Switching unit 32 Accelerator sensor 34 Brake sensor 35 CD/CS switch 36 EV auto/EV priority switch 37 CI switch 38 Battery actuator,
40 Battery 50 Electronic control unit (ECU)
51 Driving support unit 52 Hybrid electronic control unit (hybrid ECU)
60 Accelerator actuator 62 Brake actuator 64 Brake device 66 Display device 68 Meter 70 Communication device 80 Navigation system 82 Display unit 84 Map information database 100 Traffic information management center EG Engine MG Motor

Claims (1)

A control device for a hybrid vehicle having an engine, a motor, and a battery, and having a CD (Charge Depleting) mode, a CS (Charge Sustaining) mode, and a CI (Charge Increasing) mode as driving modes,
The CD mode includes an EV priority mode and an EV auto mode,
The EV priority mode is a driving mode in which EV driving, which is electric driving using the motor, is performed preferentially, and a driving force is limited compared to the EV auto mode.
A driving support unit that supports driving of the hybrid vehicle;
a switching unit operable by a passenger of the hybrid vehicle to switch the driving mode;
A control unit that controls the driving mode in response to an operation of the switching unit ,
the switching unit includes a first switching unit for switching between the CD mode and the CS mode, a second switching unit for switching between the EV priority mode and the EV auto mode, and a third switching unit for switching to the CI mode;
the driving support unit executes driving support control for driving according to a driving plan in which either the EV auto mode or the CS mode of the CD mode is assigned to each driving section of a planned driving route from a current location to a destination,
When the first switching unit or the second switching unit is operated during execution of the driving assistance control, the control unit ends the driving assistance control and switches the driving mode to the EV priority mode,
A control device for a hybrid vehicle , wherein when the third switching unit is operated while the driving assistance control is being executed, the control unit terminates the driving assistance control and switches the driving mode to the CI mode .

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