Hybrid electric vehicle

Abstract

The invention relates to a hybrid electric vehicle. A control device for a hybrid electric vehicle executes travel assistance control for performing travel on the basis of a travel assistance plan in which a motor travel mode or a normal travel mode is assigned to each travel section using information of each travel section based on a plan or an estimated travel route based on map information and the position of the vehicle. Furthermore, when a specific travel section having a motor travel designation point to be reached by motor travel exists in each travel section in the travel route, the control device divides the specific travel section into two travel sections on the basis of a predetermined condition, with the motor travel designation point as a reference, and performs travel assist control.

Description

Technical Field

[0001] The present disclosure relates to a hybrid electric vehicle. Background Art

[0002] Conventionally, as such a hybrid electric vehicle, a scheme has been proposed that switches between a motor mode for running with an electric motor alone, an engine mode for running with an engine alone, and a combined mode for running with both motors according to a mode switching vehicle speed (for example, see Japanese Patent Application Laid-Open No. 06-187595). In this hybrid electric vehicle, by switching the mode switching vehicle speed according to various environments such as urban areas, suburbs, highways, and tunnels, it is possible to run in a manner suitable for the environment. Summary of the invention

[0003] In recent years, in order to suppress the noise around the home, the user sometimes sets a motor driving area around the home. In this case, the motor driving area is set for the driving interval on the map. When the driving assistance plan is made with the home set as the destination, the motor driving is allocated to the driving interval including the home. Therefore, when the home is in the middle of the driving interval, the driving assistance plan is made with the motor driving also in the part of the driving interval beyond the home, so it is impossible to make a more appropriate driving assistance plan.

[0004] The main purpose of the hybrid electric vehicle disclosed in the present invention is to create a more appropriate driving assistance plan.

[0005] In order to achieve the above-mentioned main object, the hybrid electric vehicle of the present disclosure adopts the following means.

[0006] The hybrid electric vehicle disclosed in the present invention is characterized by comprising:

[0007] The engine can output power for driving;

[0008] A motor capable of outputting power for driving;

[0009] a power storage device capable of exchanging electric power with the motor; and

[0010] A control device that controls the engine and the motor by switching between a motor driving mode and a normal driving mode, and executes driving assistance control for driving based on a driving assistance plan, wherein the motor driving mode is a mode of motor driving in which the vehicle is driven by power from the motor while the engine is stopped, and the normal driving mode is a mode of normal driving in which the vehicle is driven by power from the engine and power from the motor as needed, and the driving assistance plan allocates the motor driving mode or the normal driving mode to each driving section using information of each driving section of a planned or estimated driving route based on map information and a position of the vehicle,

[0011] When there is a specific driving section having a motor driving designated point to be reached by motor driving among the driving sections of the driving route, the control device divides the specific driving section into two driving sections based on the motor driving designated point based on a predetermined condition and executes the driving assist control.

[0012] The hybrid electric vehicle of the present disclosure comprises:

[0013] The engine can output power for driving;

[0014] A motor capable of outputting power for driving;

[0015] a power storage device capable of exchanging electric power with the motor; and

[0016] The control device 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 power from the motor as needed. The control device performs driving assistance control for driving based on a driving assistance plan that allocates the motor driving mode or the normal driving mode to each driving section using information of each driving section of a planned or estimated driving route based on map information and a position of the vehicle.

[0017] When a specific travel section having a motor travel designated point to be reached by motor travel is included in each travel section in the travel route, the control device divides the specific travel section into two travel sections based on the motor travel designated point based on a predetermined condition and executes travel assist control.

[0018] Thus, a driving assistance plan can be prepared using two driving sections obtained by dividing a specific driving section having a motor driving designated point to be reached by motor driving based on the motor driving designated point. As a result, a driving assistance plan can be prepared more appropriately than when a driving assistance plan is prepared using the specific driving section as one driving section.

[0019] In the hybrid electric vehicle disclosed herein, when a first condition that the motor driving designated point is a set or estimated destination or an additional destination is satisfied as the predetermined condition, the control device may divide the specific driving interval into two driving intervals based on the motor driving designated point.

[0020] In this way, the driving assistance plan can be prepared using only the driving sections on the side that reaches the motor driving designated point in the divided driving section.

[0021] In this case, when the first condition is satisfied as the predetermined condition, the control device may set a first half of the specific traveling section divided into two as the motor traveling section.

[0022] In the hybrid electric vehicle of the present disclosure, when a second condition that the motor driving designated point is a via point before a set destination is satisfied as the predetermined condition, the control device may not divide the specific driving section based on the motor driving designated point.

[0023] In this way, it is possible to more appropriately handle the cases where the motor travel designated point is the destination and the case where it is an intermediate point.

[0024] In this case, when the second condition is satisfied as the predetermined condition, the control device may execute the travel assist control without using the specific travel section as the motor travel section. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Features, advantages, and technical and industrial significance of exemplary embodiments of the present invention will be described below with reference to the accompanying drawings, in which like reference numerals represent like elements, and in which:

[0026] Figure 1 This is a block diagram showing an example of a hybrid electric vehicle 20 as one embodiment of the present disclosure as blocks, with the hybrid ECU 50 as the center;

[0027] Figure 2 is a flowchart showing an example of the driving assist control executed by the hybrid ECU 50;

[0028] Figure 3 is an explanatory diagram showing an example of a situation where a travel section including a home is divided into two; and

[0029] Figure 4 This is an explanatory diagram showing an example of a situation in which the home is a stopover point before the destination. DETAILED DESCRIPTION

[0030] Next, a mode (embodiment) for carrying out the present disclosure will be described. Figure 1This is a block diagram showing an example of a hybrid electric vehicle 20 as an embodiment of the present disclosure as a block with a hybrid electronic control unit (hereinafter referred to as a hybrid ECU) 50 as the center. As shown in the figure, the hybrid electric vehicle 20 of the embodiment is equipped with an engine EG and a motor MG as power sources. The hybrid electric vehicle 20 of the embodiment has a motor driving mode and a normal driving mode as driving modes. In the motor driving mode, the hybrid electric vehicle 20 drives by the power from the motor MG in a state where the operation of the engine EG is stopped. In the normal driving mode, the engine EG is operated as needed, and the hybrid electric vehicle 20 drives using the power from the engine EG and the power from the motor MG. In the normal driving mode, there is a power consumption mode (CD (Charge Depleting) mode) that prioritizes electric driving in a manner that reduces the power storage ratio SOC of the battery 40. In addition, in the normal driving mode, there is also a power maintenance mode (CS (Charge Sustaining) mode) that uses both electric driving and hybrid driving in a manner that maintains the power storage ratio SOC of the battery 40 at a target ratio.

[0031] The hybrid electric vehicle 20 of the embodiment includes, in addition to a power source, an ignition switch 21, a global positioning system (Global Positioning Satellite, GPS) 22, a vehicle-mounted 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 switching switch 36, a battery actuator 38, a battery 40, an air-conditioning electronic control unit (hereinafter, air-conditioning ECU) 42, an air-conditioning compressor 44, a hybrid ECU 50, an accelerator actuator 60, a brake actuator 62, a brake device 64, a display device 66, a driving state indicator 67, a meter 68, a data communication module (Data Communication Module, DCM) 70, a navigation system 80, and the like.

[0032] The GPS 22 is a device that detects the position of the vehicle based on signals transmitted from a plurality of GPS satellites. The vehicle-mounted camera 24 is a camera that captures the surroundings of the vehicle, such as a front camera that captures the front of the vehicle, a rear camera that captures the rear of the vehicle, etc. The millimeter wave radar 26 detects the inter-vehicle distance and relative speed between the vehicle in front, or detects the inter-vehicle distance and relative speed between the vehicle in front, or detects the inter-vehicle distance and relative speed between the vehicle in the rear.

[0033] The acceleration sensor 28 is a sensor that detects, for example, the acceleration in the front-rear direction of the vehicle or the acceleration in the left-right direction (lateral direction) of the vehicle. The vehicle speed sensor 30 detects the vehicle speed based on the wheel speed, etc. The accelerator sensor 32 detects the accelerator opening corresponding to the amount of the driver's stepping on the accelerator pedal, etc. The brake sensor 34 detects the brake position, etc., which is the amount of the driver's stepping on the brake pedal. The mode switching switch 36 is arranged near the steering wheel of the driver's seat and is a switch for switching between the motor driving mode and the normal driving mode.

[0034] The battery actuator 38 detects the state of the battery 40, such as the voltage between the terminals, the charge and discharge current, and the battery temperature, and manages the battery 40 based on these. The battery actuator 38 calculates the storage ratio SOC, which is the ratio of the remaining storage capacity to the total storage capacity, based on the charge and discharge current. In addition, the battery actuator 38 calculates the maximum allowable output power (output limit Wout) that can be output from the battery 40 and the maximum allowable input power (input limit Win) that can be input to the battery 40 based on the storage ratio SOC, the battery temperature, etc. The battery 40 is configured as a secondary battery that can be charged and discharged, and for example, a lithium ion battery, a nickel-hydrogen battery, a lead storage battery, etc. can be used.

[0035] Although not shown in the figure, the air conditioning ECU 42 is configured as a microcomputer centered around a CPU, and in addition to the CPU, it also includes a ROM, a RAM, a flash memory, an input port, an output port, a communication port, etc. The air conditioning ECU 42 is assembled in an air conditioning device that performs air conditioning in the passenger compartment, and drives and controls an air conditioning compressor 44 in the air conditioning device so that the temperature of the passenger compartment becomes a set temperature.

[0036] The engine EG is configured as an internal combustion engine, for example. The motor MG is configured as 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 the power supplied from the battery 40 or charge the battery 40 using the generated power.

[0037] Although not shown, the hybrid ECU 50 is configured as a microcomputer centered around a CPU, and in addition to the CPU, it also includes a ROM, a RAM, a flash memory, an input port, an output port, a communication port, etc. The hybrid ECU 50 sets the driving mode, or sets the target operating point (target speed, 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 limit and input limit from the battery actuator 38. It should be noted that the hybrid ECU 50 is not started when the accessory is turned on, but is started when it is ready.

[0038] During motor running, the hybrid ECU 50 sets the required driving force and the required power based on the accelerator opening from the accelerator sensor 32 and the vehicle speed from the vehicle speed sensor 30. Then, the hybrid ECU 50 sets the torque command of the motor MG so that the required driving force and the required power are output to the vehicle, and sends the set torque command to the accelerator actuator 60. During hybrid running, the hybrid ECU 50 sets the target operating point of the engine EG and the torque command of the motor MG so that the required driving force and the required power are output to the vehicle. Then, the hybrid ECU 50 sends the target operating point and the torque command to the accelerator actuator 60. In addition, when the brake pedal is stepped on, the hybrid ECU 50 sets the required braking force based on the brake position from the brake sensor 34 and the vehicle speed from the vehicle speed sensor 30. The hybrid ECU 50 sets the regenerative torque command for regenerative control of the motor MG based on the required braking force and the vehicle speed, and sets the target braking force of the brake device. Then, the hybrid ECU 50 sends the torque command to the accelerator actuator 60 and sends the target braking force to the brake actuator 62.

[0039] The accelerator actuator 60 controls the driving of the engine EG and the motor MG according to the target operating point and the torque command set by the hybrid ECU 50. The accelerator actuator 60 controls the intake air amount, fuel injection, ignition, intake valve opening and closing timing, etc. so that the engine EG is operated at the target operating point (target speed, target torque). In addition, the accelerator actuator 60 controls the switching of the switching element of the inverter for driving the motor MG so that the torque equivalent to the torque command is output from the motor MG.

[0040] The brake actuator 62 controls the brake device 64 so that the target braking force set by the hybrid ECU 50 acts on the vehicle through the brake device 64. The brake device 64 is configured as a hydraulically driven friction brake, for example.

[0041] The display device 66 is assembled, for example, on a mounting panel in front of the driver's seat, and displays various information and also functions as a touch panel. Although not shown, the driving state indicator 67 has an EV indicator and an HV indicator. When the hybrid electric vehicle 20 is motor-driven, the EV indicator is turned on and the HV indicator is turned off. When the hybrid electric vehicle 20 is hybrid-driven, the EV indicator is turned off and the HV indicator is turned on. The meter 68 is assembled, for example, on a mounting panel in front of the driver's seat.

[0042] The data communication module (DCM) 70 sends the information of the vehicle to the traffic information management center 100, or receives the road traffic information from the traffic information management center 100. As the information of the vehicle, for example, the position, speed, driving power, driving mode, etc. of the vehicle can be listed. As the road traffic information, for example, information related to current and future congestion, information related to the current average speed in the section on the driving path, information related to the predicted value of the future average speed, information related to traffic control, information related to weather, information related to road surface conditions, information related to maps, etc. can be listed. DCM70 communicates with the traffic information management center 100 at predetermined intervals (for example, every 30 seconds, every 1 minute, every 2 minutes, etc.).

[0043] The navigation system 80 is a system for guiding the vehicle to the set destination, and 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 position, etc. on the display device 66 based on the map information. The navigation system 80 communicates with the traffic information management center 100 via the data communication module (DCM) 70. When the destination and the via point are set, the navigation system 80 sets the route based on the information of the destination and the via point, the information of the current position (the current position of the vehicle) obtained by the GPS 22, and the information stored in the map information database 84. Then, the navigation system 80 communicates with the traffic information management center 100 at predetermined intervals (for example, every 3 minutes, every 5 minutes, etc.) to obtain road traffic information, and performs route guidance based on the road traffic information. The map information stored in the map information database 84 includes not only map data but also road slopes, road types, elevations, etc., for each travel interval.

[0044] When the navigation system 80 performs route guidance, every time the road traffic information is obtained from the traffic information management center 100 (or at predetermined intervals), the load information required for traveling in each driving section is generated based on the information of each driving section in the driving route, the information related to the driving load, the vehicle speed, the driving power of the vehicle, the driving mode of the vehicle, etc. in the road traffic information obtained from the traffic information management center 100, and the load information required for traveling in each driving section is generated as pre-read information, and sent to the hybrid ECU 50. It should be noted that the pre-read information also includes the information of the vehicle such as the position, speed, driving power, and driving mode of the vehicle, information related to current and future congestion, information related to the current average vehicle speed in the section on the driving route, information related to the predicted value of the future average vehicle speed, information related to traffic control, information related to weather, information related to road surface conditions, information related to maps, etc. The map-related information also includes the area (motor driving area) determined by the city, town, etc. to be driven by motors. The navigation system 80 can also set the motor driving area by specifying an area near the user's home through user operation. The navigation system 80 transmits a signal to the hybrid ECU 50 indicating whether the vehicle is in the motor driving area while the vehicle is running.

[0045] Next, the operation of the hybrid electric vehicle 20 configured in this manner, particularly the operation when a driving assistance plan is created and the vehicle travels according to the created driving assistance plan, will be described. Figure 2 2 is a flowchart showing an example of the driving assist control executed by the hybrid ECU 50. This flowchart is executed after the ignition switch 21 is turned on.

[0046] In the driving assist control, first, the hybrid ECU 50 determines whether the driving assist control can be executed (S100). When the navigation system 80 is abnormal, the GPS 22 is abnormal, etc., and the route guidance cannot be performed well, the driving assist control cannot be executed. When the battery temperature is low, the maximum allowable output power that can be output from the battery 40, that is, the output limit Wout becomes smaller, and even if driving in the CD mode, the engine EG will be frequently started, and driving based on the CD mode cannot be properly performed. In S100, it is determined whether the driving assist control can be executed based on these situations. When it is determined in S100 that the driving assist control cannot be executed, standby until the driving assist control can be executed.

[0047] When the hybrid ECU 50 determines that the driving assist control can be executed in S100, it determines whether the pre-read information sent from the navigation system 80 has been updated (S110). When the hybrid ECU 50 determines that the pre-read information has been updated, it obtains information on a planned or estimated driving route within a predetermined range from the current position (S120). The predetermined range can be 5km, 10km, 15km, etc. The planned driving route is a driving route guided by the navigation system 80 as a route from the current position to the destination by setting a destination, and the estimated driving route is a driving route estimated to be driven from the current position.

[0048] Next, the hybrid ECU 50 determines whether the home is a planned destination or an estimated destination (S130). When the navigation system 80 sets the home as the destination for route guidance, the home is planned as the destination in the driving assistance plan. In addition, when the navigation system 80 is not providing route guidance, when driving toward the home, it is estimated that the home is the destination. Therefore, S130 makes an affirmative determination when the home is set as the destination for route guidance, and when driving toward the home without route guidance. In this case, the hybrid ECU 50 divides the driving interval including the home into two driving intervals based on the home (S140). Then, the hybrid ECU 50 sets the first half of the two driving intervals divided into two (the driving interval on the side closer to the current position point) as the motor driving interval driven by the motor (S150).

[0049] exist Figure 3 , an example of a case where the driving range including the home is divided into two. As shown in the figure, the first half of the two driving ranges divided into two based on the home (the driving range on the side close to the current position point) is set as the motor driving range and used for the driving assistance plan. On the other hand, the second half of the driving range (the driving range on the side far from the current position point) is not used for the driving assistance plan.

[0050] In this way, when the hybrid ECU 50 divides the driving range including the home into two based on the home, and when it is determined in S130 that the home is not the planned destination or the estimated destination, the hybrid ECU 50 determines whether the home is a via point in the route guidance before the destination (S160). When it is determined that the home is a via point in the route guidance, the driving range including the home is set as a normal driving range (a range that is not a motor driving range) (S170). Setting the driving range including the home as a normal driving range in this way is based on treating the vehicle as the same vehicle as other vehicles. Figure 4, which shows an example of a case where the home is a stopover point to the destination. In this case, since the home is a stopover point (passing point) in the route guidance before the destination, the travel section including the home is set as a normal travel section like other vehicles.

[0051] Next, the hybrid ECU 50 creates a driving assistance plan (S180). The driving assistance plan, for example, allocates the motor driving mode to the motor driving section in each driving section of the driving route. For other driving sections, the energy consumption E(n) of each driving section of the driving route from the current position to the control end section (destination) and the total energy Esum as the sum thereof are calculated, and the energy consumption E(n) of the driving section (motor driving section) to which the motor driving mode is allocated is subtracted from the total energy Esum to calculate the remaining total energy Eev. When the remaining total energy Eev is less than the remaining amount of the battery 40, the CD mode is allocated to all driving sections. When the remaining total energy Eev is greater than the remaining amount of the battery 40, the other driving sections are rearranged in order of driving load from low to high. The driving assistance plan can be created by allocating the CD mode in order of driving load from low to high until the sum of the energy consumption En of the allocated driving sections exceeds the remaining amount of the battery 40, and allocating the CS mode to the remaining driving sections. When the home is set as the destination, the driving section including the home is divided into two, and the driving assistance plan is prepared using the first half of the driving section set as the motor driving section in the divided driving section. Therefore, the driving assistance plan can be prepared more appropriately than when the driving section including the home is not divided into two and is directly used to prepare the driving assistance plan.

[0052] Then, the hybrid ECU 50 controls the driving mode according to the driving assistance plan (S190), and determines whether the control end condition is satisfied (S200). When the hybrid ECU 50 determines that the control end condition is not satisfied, the process returns to S100 to determine whether the driving assistance control can be executed. When it is determined that the control end condition is satisfied, the driving assistance control is terminated.

[0053] In the hybrid electric vehicle 20 of the embodiment described above, when the home is a planned destination or an estimated destination, the driving interval including the home is divided into two driving intervals based on the home, and the first half of the two driving intervals divided into two is set as the motor driving interval. Then, the driving assistance plan is prepared using the first half of the two driving intervals divided into two using the home as the planned or estimated destination. As a result, the driving assistance plan can be prepared more appropriately than when the driving assistance plan is prepared using the driving interval including the home.

[0054] In the hybrid electric vehicle 20 of the embodiment, when the home is a via point in the route guidance, the driving section including the home is not divided into two but is set as one driving section as a normal driving section, and the driving assistance plan is prepared using the driving section. This makes it possible to more appropriately handle the case where the home is the destination and the case where the home is a via point.

[0055] In the hybrid electric vehicle 20 of the embodiment, when the vicinity of the home is set as the motor driving area, the driving section including the home is divided into two driving sections based on the home when the home is the planned destination or the estimated destination. However, the vicinity of a predetermined specific place such as a hospital or a school may be set as the motor driving area, and when the specific place is the destination, the driving section including the specific place may be divided into two driving sections based on the hospital or the school.

[0056] In the hybrid electric vehicle 20 of the embodiment, when the home is the planned destination or the estimated destination, the travel section including the home is divided into two travel sections based on the home. However, when the home is not the final destination but an additional destination on the way, the travel section including the home may be divided into two travel sections based on the home.

[0057] The correspondence between the main elements of the embodiment and the main elements of the invention described in the column of means for solving the problem is explained. In the embodiment, the engine EG is equivalent to the "engine", the motor MG is equivalent to the "motor", the battery 40 is equivalent to the "power storage device", and the hybrid electronic control unit 50 is equivalent to the "control device".

[0058] It should be noted that since the embodiment is an example of a method for specifically describing the method for implementing the invention recorded in the column of means for solving the problem, the correspondence between the main elements of the embodiment and the main elements of the invention recorded in the column of means for solving the problem does not limit the elements of the invention recorded in the column of means for solving the problem. That is, the interpretation of the invention recorded in the column of means for solving the problem should be based on the description in that column, and the embodiment is only a specific example of the invention recorded in the column of means for solving the problem.

[0059] As mentioned above, although this disclosure was demonstrated using embodiment, this disclosure is not limited to such embodiment at all, It is a matter of course that this disclosure can be implemented in various forms within the range which does not deviate from the summary of this disclosure.

[0060] The present disclosure can be utilized in the hybrid electric vehicle manufacturing industry and the like.

Claims

1. A hybrid electric vehicle, characterized in that: have: The engine can output power for driving; A motor capable of outputting power for driving; a power storage device capable of exchanging electric power with the motor; as well as A control device that controls the engine and the motor by switching between a motor driving mode and a normal driving mode, and executes driving assistance control for driving based on a driving assistance plan, wherein the motor driving mode is a mode of motor driving in which the vehicle is driven by power from the motor while the engine is stopped, and the normal driving mode is a mode of normal driving in which the vehicle is driven by power from the engine and power from the motor as needed, and the driving assistance plan allocates the motor driving mode or the normal driving mode to each driving section using information of each driving section of a planned or estimated driving route based on map information and a position of the vehicle, When there is a specific driving section having a motor driving designated point to be reached by motor driving in each driving section in the driving route, the control device divides the specific driving section into two driving sections based on the motor driving designated point based on a predetermined condition and performs the driving assist control.

2. The hybrid electric vehicle according to claim 1, wherein: When a first condition that the designated motor travel point is a set or estimated destination or an additional destination is satisfied as the predetermined condition, the control device divides the specific travel section into two travel sections based on the designated motor travel point.

3. The hybrid electric vehicle according to claim 2, wherein: When the first condition is satisfied as the predetermined condition, the control device sets a first half of the specific traveling section divided into two as a motor traveling section.

4. The hybrid electric vehicle according to claim 1, wherein: When a second condition that the motor driving designated point is a stopover point before a set destination is satisfied as the predetermined condition, the control device does not divide the specific driving section based on the motor driving designated point.

5. The hybrid electric vehicle according to claim 4, wherein: When the second condition is satisfied as the predetermined condition, the control device executes the travel assist control without using the specific travel section as a motor travel section.

Images