Hybrid vehicle

Abstract

To promote charging of a power storage device by a charger before system startup.SOLUTION: A control device of a hybrid vehicle executes travel support control such that the vehicle travels on the basis of a travel support plan in which, by using information on each travel section of a planned or estimated travel route based on map information and an own vehicle position, a motor travel mode or a normal travel mode is assigned to each travel section. In addition, when there is a motor travel area section which is included among the travel sections in the travel route, and in which the vehicle is to travel by motor travel, the control device prohibits precharge for charging a power storage device before the motor travel area section is reached if a power storage ratio of the power storage device has no history of reaching a prescribed ratio or greater after system startup.SELECTED DRAWING: Figure 2

Description

[Technical Field]

[0001] The present disclosure relates to hybrid vehicles. [Background technology]

[0002] Conventionally, hybrid vehicles of this type have been proposed that, when a specific section where engine operation is restricted exists on the predicted driving route, provide driving assistance by ensuring a battery charge that is a margin above the required battery charge for driving through the specific section using motor driving (see, for example, Patent Document 1). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Publication No. 2023-120671 Summary of the Invention [Problem to be solved by the invention]

[0004] In a hybrid vehicle (so-called plug-in hybrid vehicle) equipped with a charger that charges an on-board power storage device using electric power from an external power source, the vehicle runs on motor power until the remaining capacity of the power storage device becomes low, and when the remaining capacity of the power storage device becomes low, the engine is started and the vehicle runs in hybrid power mode. In such a hybrid vehicle, it is desirable to promote charging of the power storage device by the charger before starting the system.

[0005] The hybrid vehicle of the present disclosure has a primary objective of promoting charging of the power storage device by a charger before the system is started. [Means for solving the problem]

[0006] The hybrid vehicle of the present disclosure employs the following measures to achieve the above-mentioned main object.

[0007] The hybrid vehicle disclosed herein is a hybrid vehicle equipped with an engine capable of outputting power for driving, a motor capable of outputting power for driving, a storage device capable of exchanging power with the motor, a charger that charges the storage device using power from an external power source, and a control device that controls the engine and the motor by switching between a motor driving mode in which the vehicle is driven by power from the motor while the engine is stopped, and a normal driving mode in which the vehicle is driven by power from the engine and a normal driving mode as needed, and that executes driving assistance control to drive the vehicle based on a driving assistance plan that assigns the motor driving mode or the normal driving mode to each driving section of a planned or estimated driving route based on map information and the vehicle's position, and is characterized in that when there is a motor driving range section among the driving sections on the driving route where the vehicle should be driven by motor driving, the control device prohibits pre-charging to charge the storage device before reaching the motor driving range section if there is no history of the storage ratio of the storage device reaching a predetermined ratio or higher after the system is started.

[0008] In the hybrid vehicle disclosed herein, if there is no history of the power storage device's power storage rate reaching or exceeding a predetermined rate after system startup, pre-charging of the power storage device before the vehicle reaches the motor driving range is prohibited, thereby facilitating charging of the power storage device by a charger to a predetermined rate or higher before system startup. The predetermined rate can be, for example, 50%, 70%, or 80% of the power storage rate SOC. [Brief explanation of the drawings]

[0009] [Figure 1] 1 is a block diagram showing an example of a hybrid vehicle 20 according to an embodiment. [Figure 2] 4 is a flowchart illustrating an example of driving support control. DETAILED DESCRIPTION OF THE INVENTION

[0010] Next, a mode (embodiment) for carrying out the present disclosure will be described. FIG. 1 is a block diagram illustrating an example of a hybrid vehicle 20 according to an embodiment of the present disclosure, focusing on a hybrid electronic control unit (hereinafter referred to as a hybrid ECU) 50. As shown in the figure, the hybrid vehicle 20 according to the embodiment is configured as a hybrid vehicle (a so-called plug-in hybrid vehicle (PHEV)) that includes an engine EG and a motor MG as power sources and a charger 46 that charges a battery 44 using external power. The hybrid vehicle 20 according to the embodiment has two driving modes: a motor driving mode in which the vehicle runs on power from the motor MG with the engine EG stopped, and a normal driving mode in which the engine EG is operated as needed and the vehicle runs on power from the engine EG and the motor MG. The normal driving mode includes a CD mode (Charge Depleting mode) that prioritizes electric driving so as to reduce the state of charge (SOC) of the battery 44, and a CS mode (Charge Sustaining mode) that combines electric driving and hybrid driving so as to maintain the state of charge (SOC) of the battery 44 at a target rate.

[0011] In addition to the power source, the hybrid vehicle 20 of this embodiment is equipped with an ignition switch 21, a GPS (Global Positioning System, Global Positioning Satellite) 22, an on-board camera 24, a millimeter-wave radar 26, an acceleration sensor 28, a vehicle speed sensor 30, an accelerator sensor 32, a brake sensor 34, a mode selector switch 36, an air conditioner electronic control unit (hereinafter referred to as the air conditioner ECU) 38, an air conditioner compressor 40, a battery actuator 42, a battery 44, a charger 46, a hybrid ECU 50, an accelerator actuator 60, a brake actuator 62, a brake device 64, a display device 66, a driving status indicator 67, a DCM (Data Communication Module) 70, a navigation system 80, and the like.

[0012] The battery actuator 42 detects the state of the battery 44, such as the terminal voltage, charge / discharge current, and battery temperature, and manages the battery 44 based on these. The battery actuator 42 calculates the power storage ratio SOC as the ratio of the remaining power storage capacity to the total power storage capacity based on the charge / discharge current, and calculates the maximum allowable output power (output limit Wout) that may be output from the battery 44 and the maximum allowable input power (input limit Win) that may be input to the battery 44 based on the power storage ratio SOC, battery temperature, etc. The battery 44 may be, for example, a lithium-ion battery. The charger 46 charges the battery 44 using power from an external power source 110, such as a commercial power source.

[0013] 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 a battery 44 via an inverter (not shown), and can output driving force using power supplied from the battery 44 and charge the battery 44 with the generated power.

[0014] The hybrid ECU 50 is configured as a microcomputer centered around a CPU (not shown), and sets the driving mode and also 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 set driving mode, the accelerator opening from the accelerator sensor 32, the brake position from the brake sensor 34, and the output and input limits from the battery actuator 42.

[0015] When driving by motor, hybrid ECU 50 sets a torque command for motor MG based on the accelerator opening from accelerator sensor 32 and the vehicle speed from vehicle speed sensor 30, and sends the set torque command to accelerator actuator 60. When driving by hybrid, hybrid ECU 50 sets a target operating point for engine EG and a torque command for motor MG so as to output a required driving force and a required power to the vehicle, and sends the target operating point and torque command to accelerator actuator 60. When the brake pedal is depressed, hybrid ECU 50 sets a required braking force based on the brake position from brake sensor 34 and the vehicle speed from vehicle speed sensor 30, and sets a regenerative torque command for regenerative control of motor MG and a target braking force by the brake device based on the required braking force and the vehicle speed, and sends the torque command to accelerator actuator 60 and the target braking force to brake actuator 62.

[0016] The accelerator actuator 60 controls the intake air amount, fuel injection, ignition, intake valve opening / closing timing, etc. so that the engine EG is operated at a target operating point (target rotation speed and target torque). The accelerator actuator 60 controls the switching of switching elements of an inverter that drives the motor MG so that a torque corresponding to a torque command is output from the motor MG. The brake actuator 62 controls the brake device 64 so that a target braking force is applied to the vehicle by the brake device 64.

[0017] The DCM (Data Communication Module) 70 communicates with the traffic information management center 100 at predetermined intervals (for example, every 30 seconds, every minute, or every two minutes), transmits information about the vehicle to the traffic information management center 100, and receives road traffic information from the traffic information management center 100. Examples of the vehicle information include the vehicle's position, vehicle speed, driving power, and driving mode. Examples of the road traffic information include information about current and future congestion, information about the current average vehicle speed and predicted future average vehicle speed in sections along the travel route, information about traffic regulations, information about weather, information about road surface conditions, and information about maps.

[0018] The navigation system 80 includes a display unit 82 and a map information database 84. The display unit 82 is a functional block having a function of displaying the route to the destination, the vehicle's position, and the like on the display device 66 based on map information. When the destination and waypoints are set, the navigation system 80 sets a route based on the information about the destination and waypoints, information about the current location (current vehicle position) acquired by the GPS 22, and information stored in the map information database 84. When providing route guidance, the navigation system 80 generates, as look-ahead information, information about each traveling section within the traveling route and information about the traveling load, which are included in the road traffic information acquired from the traffic information management center 100, as well as load information required to travel each traveling section based on the vehicle's speed, the vehicle's traveling power, the vehicle's traveling mode, and the like, and transmits the information to the hybrid ECU 50. The look-ahead information includes information about the vehicle, such as the vehicle's position, vehicle speed, driving power, and driving mode, as well as information about current and future traffic congestion, information about the current average vehicle speed and predicted future average vehicle speed for sections of the driving route, information about traffic regulations, information about weather, information about road surface conditions, and information about maps. The map information also includes areas where motor driving is required (motor driving areas) designated by municipalities and the like. The navigation system 80 can also set a motor driving area by specifying an area, such as an area near the user's home, through user operation.

[0019] Next, the operation of the hybrid vehicle 20 configured as described above, and the operation when the hybrid vehicle 20 travels in the motor driving range in accordance with the driving support plan, will be described. Fig. 2 is a flowchart showing an example of driving support control executed by the hybrid ECU 50. This flowchart is executed after the ignition switch 21 is turned on.

[0020] When driving assist control is executed, the hybrid ECU 50 first determines whether the look-ahead information transmitted from the navigation system 80 has been updated (step S100). If it determines that the look-ahead information has been updated, the hybrid ECU 50 acquires information on a planned or estimated driving route within a predetermined range from the current location (step S110). The predetermined range can be 10 km, 20 km, or up to the destination. The planned driving route is a driving route planned by the navigation system 80 as route guidance from the current location to the destination when the destination is set, and the estimated driving route is a driving route estimated to be traveled from the current location.

[0021] Next, a driving assistance plan is created (step S120). The driving assistance plan can be created by, for example, assigning the motor driving mode to the motor driving sections of each driving section of the driving route, and for the other driving sections, calculating the total energy Esum as the sum of the energy consumption E(n) of each driving section of the driving route from the current location to the control end section (destination), subtracting the energy consumption E(n) of the driving section (motor driving section) assigned the motor driving mode from the total energy Esum to calculate the total remaining energy Eev, and assigning the CD mode to all driving sections when the total remaining energy Eev is equal to or less than the remaining charge of the battery 44, and when the total remaining energy Eev is greater than the remaining charge of the battery 44, sorting the other driving sections in order of decreasing driving load, and assigning them to the CD mode in order of decreasing driving load until the sum of the energy consumption En of the assigned driving sections exceeds the remaining charge of the battery 44, and assigning the remaining driving sections to the CS mode. Then, the driving mode is controlled in accordance with the driving assistance plan (step S130).

[0022] When it is determined in step S100 that the look-ahead information has not been updated, or when it is determined in step S100 that the look-ahead information has been updated, a driving support plan is created, and driving mode control in accordance with the driving support plan is started, it is determined whether the power storage percentage SOC of the battery 44 is equal to or greater than a predetermined percentage Sref (step S140). If it is determined that the power storage percentage SOC of the battery 44 is equal to or greater than the predetermined percentage Sref, the SOC permission history is turned on (step S150). The predetermined percentage Sref can be a value that is considered sufficient as the power storage percentage SOC of the battery 44 before the ignition switch 21 is turned on, such as 50%, 60%, or 70%. This driving support control is repeatedly executed until a termination condition is met. Therefore, if the power storage percentage SOC of the battery 44 is equal to or greater than the predetermined percentage Sref at least once after the ignition switch 21 is turned on, the SOC permission history is turned on.

[0023] Next, it is determined whether the planned or estimated travel route includes a motor-driven region (step S160). If it is determined that a motor-driven region exists, the energy Eev required to travel through the motor-driven region is estimated (step S170). A start-point distance Dstart from the current location to the start point of the motor-driven region and an end-point distance Dend to the end point of the motor-driven region are calculated (step S180). It is then determined whether the start-point distance Dstart is less than a point distance Dref1 at which the start of motor-driven travel is requested (step S160). If it is determined that the start-point distance Dstart is equal to or greater than the point distance Dref1, it is determined whether the start-point distance Dstart is less than a point distance Dref2 at which pre-charging of the battery 44 by hybrid travel is initiated in order to increase the state of charge (SOC) of the battery 44 in advance for motor-driven travel through the motor-driven region (step S200). If it is determined that the start-point distance Dstart is equal to or greater than the point distance Dref2, no pre-charging request is made (step S230). On the other hand, when it is determined that the start point distance Dstart is less than the point distance Dref2, it is determined whether or not the SOC permission history is ON (step S210). When it is determined that the SOC permission history is ON, a pre-charge is requested (step S220). When it is determined that the SOC permission history is OFF, a pre-charge request is not made (step S230). When a pre-charge is requested, the hybrid ECU 50 switches the driving mode to the hybrid driving mode and charges the battery 44. When it is determined in step S190 that the start point distance Dstart is less than the point distance Dref1, a request for motor driving is made (step S240). When motor driving is requested, the hybrid ECU 50 switches the driving mode to the motor driving mode and performs motor driving.

[0024] If it is determined in step S160 that there is no motor driving area on the planned or estimated driving route, the energy Eev required to drive in the motor driving area, the start point distance Dstart, and the end point distance Dend are set to a value of 0 (step S250).

[0025] Then, it is determined whether or not the control termination condition is satisfied (step S260). If it is determined that the control termination condition is not satisfied, the process returns to step S100 of the process of determining whether or not the look-ahead information has been updated, and if it is determined that the control termination condition is satisfied, the driving support control is terminated.

[0026] In the hybrid vehicle 20 of the embodiment described above, when the planned or estimated driving route includes a motor driving area, if the SOC permission history is set to ON because the power storage percentage SOC of the battery 44 is equal to or greater than the predetermined percentage Sref after the ignition switch 21 is turned ON, the battery 44 is pre-charged, but if the SOC permission history is set to OFF, the battery 44 is not pre-charged. This makes it possible to encourage the power storage percentage SOC of the battery 44 to be equal to or greater than the predetermined percentage Sref before the ignition switch 21 is turned ON (before the system is started). As a result, charging of the battery 44 by the charger 46 using power from the external power source 110 before the system is started can be promoted.

[0027] In the hybrid vehicle 20 of the embodiment, the battery 44 is pre-charged when the SOC permission history is turned on because the power storage percentage SOC of the battery 44 is equal to or higher than the predetermined percentage Sref after the ignition switch 21 is turned on, but the battery 44 may be pre-charged if there is a history of switching to the hybrid driving mode after the ignition switch 21 is turned on. On the other hand, pre-charging of the battery 44 may be prohibited when the power storage percentage SOC of the battery 44 is depleted.

[0028] The present disclosure has been described above using embodiments, but the present disclosure is not limited to these embodiments in any way, and it goes without saying that the present disclosure can be embodied in various forms within the scope that does not deviate from the gist of the present disclosure. [Industrial Applicability]

[0029] The present disclosure is applicable to the hybrid vehicle manufacturing industry and the like. [Explanation of symbols]

[0030] 20 Hybrid vehicles, 44 Batteries, 46 Chargers, 50 Hybrid electronic control units (hybrid ECUs), EG engines, MG motors.

Claims

[Claim 1] a control device that executes driving assistance control for driving the vehicle based on a driving assistance plan in which the motor driving mode or the normal driving mode is assigned to each driving section of a planned or estimated driving route based on map information and a vehicle position, when controlling the engine and the motor by switching between a motor driving mode in which motor driving is performed by driving power from the motor with the engine stopped, and a normal driving mode in which normal driving is performed by driving power from the engine and the motor as necessary, The control device is characterized in that, when there is a motor driving range section among each driving section on the driving route where the vehicle should be driven by motor driving, if there is no history of the storage rate of the storage device reaching a predetermined rate or more after system startup, the control device prohibits pre-charging, which charges the storage device before the vehicle reaches the motor driving range section.

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