VEHICLE AND CONTROL METHOD FOR VEHICLE

• US 20140297087A1
• Filed: 11/04/2011
• Published: 10/02/2014
• Est. Priority Date: 11/04/2011
• Status: Active Grant

• Current Assignee: Toyota Jidosha Kabushiki Kaisha (Toyota Motor Corporation)
• Original Assignee: Toyota Jidosha Kabushiki Kaisha (Toyota Motor Corporation)
• Inventors: Amano, Takashi
• Granted Patent: US 9,376,032 B2
• Time in Patent Office: Days
• US Class Current: 701/22
• CPC Class Codes: B60K 6/445 Differential gearing distribution type
• CPC Class Codes: B60L 15/20 for control of the vehicle or its driving motor to achieve a desired performance, e.g. speed, torque, programmed variation of speed
• CPC Class Codes: B60L 15/2045 for optimising the use of energy
• CPC Class Codes: B60L 2210/10 DC to DC converters
• CPC Class Codes: B60L 2210/40 DC to AC converters
• CPC Class Codes: B60L 2240/12 Speed
• CPC Class Codes: B60L 2240/423 Torque
• CPC Class Codes: B60L 2240/547 Voltage
• CPC Class Codes: B60L 2240/549 Current
• CPC Class Codes: B60L 2240/642 Slope of road
• CPC Class Codes: B60L 50/16 with provision for separate direct mechanical propulsion
• CPC Class Codes: B60L 50/51 characterised by AC-motors
• CPC Class Codes: B60L 50/61 by batteries charged by engine-driven generators, e.g. series hybrid electric vehicles
• CPC Class Codes: B60L 58/40 for controlling a combination of batteries and fuel cells
• CPC Class Codes: B60W 10/08 including control of electric propulsion units, e.g. motors or generators
• CPC Class Codes: B60W 20/00 Control systems specially adapted for hybrid vehicles hybrid vehicle design, B60K6/00; electric vehicles B60L
• CPC Class Codes: B60W 2552/15 Road slope, i.e. the inclination of a road segment in the longitudinal direction
• CPC Class Codes: B60W 2710/086 Power
• CPC Class Codes: Y02T 10/40 Engine management systems
• CPC Class Codes: Y02T 10/62 Hybrid vehicles
• CPC Class Codes: Y02T 10/64 : Electric machine technologies in electromobility
• CPC Class Codes: Y02T 10/70 : Energy storage systems for electromobility, e.g. batteries
• CPC Class Codes: Y02T 10/7072 : Electromobility specific charging systems or methods for batteries, ultracapacitors, supercapacitors or double-layer capacitors
• CPC Class Codes: Y02T 10/72 : Electric energy management in electromobility
• CPC Class Codes: Y02T 90/16 : Information or communication technologies improving the operation of electric vehicles
• CPC Class Codes: Y02T 90/40 : Application of hydrogen technology to transportation, e.g. using fuel cells

Abstract

A vehicle includes: a motor generator generating driving power for traveling of the vehicle; an ECU for controlling the motor generator; and an inclination detecting unit for detecting an inclination of a road surface. The ECU executes a driving power change operation that causes the vehicle to travel while switching between a first state (high output state) of the motor generator where first-level driving power is generated and a second state (low output state) of the motor generator where driving power smaller than that in the first state is generated. When it is recognized that the vehicle is traveling on a downhill, based on the inclination detected by the inclination detecting unit, the ECU sets the driving power in the first state to be smaller than that when the vehicle travels on a flat road.

Claims

1. A vehicle, comprising:

a driving source generating driving power for traveling of said vehicle;

a control device for controlling said driving source; and

an inclination detecting unit for detecting an inclination of a road surface, wherein

said control device executes a driving power change operation that causes said vehicle to travel while switching between a first state of said driving source where first-level driving power is generated and a second state of said driving source where driving power smaller than that in said first state is generated,

when it is recognized that said vehicle is traveling on a downhill, based on the inclination detected by said inclination detecting unit, said control device sets the driving power in said first state to be smaller than that when said vehicle is traveling on a flat road,

during execution of said driving power change operation, said control device switches to said first state in response to a speed of said vehicle having decreased to a lower limit value within a permitted range, and switches to said second state in response to the speed of said vehicle having increased to an upper limit value within said permitted range, and

said control device sets said lower limit value when said vehicle is traveling on the downhill to be higher than that when said vehicle is traveling on the flat road.

2. The vehicle according to claim 1, wherein

when a change in driving power requested from a user is within a prescribed range, said control device executes the driving power change operation.

3. The vehicle according to claim 1, wherein

said control device switches between said first and second states such that a speed of said vehicle is maintained within an permitted range during execution of the driving power change operation.

6. The vehicle according to claim 1, wherein

when said vehicle returns from the downhill to the flat road, said control device gently decreases said lower limit value over time.

7. The vehicle according to claim 1, wherein

said control device sets the driving power in said second state when said vehicle is traveling on the downhill to be larger than the driving power in said second state when said vehicle is traveling on the flat road.

8. The vehicle according to claim 1, wherein

said driving source is a rotating electric machine, and

when said vehicle is traveling on the downhill, said control device executes a regenerative operation of said rotating electric machine in said second state.

9. The vehicle according to claim 1, wherein

said control device sets the driving power in said first state to become smaller as magnitude of said inclination in a downward direction becomes larger.

10. The vehicle according to claim 1, wherein

the driving power in said first state is set to be larger than constant reference driving power that can maintain the speed of said vehicle, and

the driving power in said second state is set to be smaller than said reference driving power.

11. The vehicle according to claim 10, wherein

said control device stops generation of the driving power from said driving source in said second state.

12. The vehicle according to claim 10, wherein

said vehicle travels mainly using inertial force of said vehicle in said second state.

13. The vehicle according to claim 1, further comprising:

another driving source generating the driving power for traveling of said vehicle, wherein

said control device executes the driving power change operation that switches between a third state of said another driving source where second-level driving power is generated and a fourth state of said another driving source where driving power smaller than that in said third state is generated.

14. The vehicle according to claim 13, wherein

said control device brings said another driving source into said third state when said driving source is in said first state, and brings said another driving source into said fourth state when said driving source is in said second state.

15. The vehicle according to claim 13, wherein

said control device sets the driving power of said another driving source in said third state when said vehicle is traveling on the downhill to be smaller than that when said vehicle is traveling on the flat road.

16. The vehicle according to claim 13, wherein

a sum of the driving power of said driving source in said first state and the driving power of said another driving source in said third state is set to be larger than constant reference driving power that can maintain the speed of said vehicle, and

a sum of the driving power of said driving source in said second state and the driving power of said another driving source in said fourth state is set to be smaller than said reference driving power.

17. The vehicle according to claim 13, wherein

one of said driving source and said another driving source is a rotating electric machine, and

the other of said driving source and said another driving source is an engine.

18. The vehicle according to claim 13, wherein

both of said driving source and said another driving source are rotating electric machines.

19. The vehicle according to claim 1, wherein

said driving source is either a rotating electric machine or an engine.

4. (canceled)

5. (canceled)

20. A control method for a vehicle having a driving source generating driving power for traveling thereof and an inclination detecting unit for detecting an inclination of a road surface, the control method comprising the steps of:

bringing said driving source into a first state where driving power of a prescribed level is generated;

bringing said driving source into a second state where driving power smaller than that in said first state is generated;

executing a driving power change operation that causes said vehicle to travel while switching between said first and second states;

when it is recognized that said vehicle is traveling on a downhill, based on the inclination detected by said inclination detecting unit, setting the driving power in said first state to be smaller than that when said vehicle is traveling on a flat road,

during execution of said driving power change operation, switching to said first state in response to a speed of said vehicle having decreased to a lower limit value within a permitted range, and switching to said second state in response to the speed of said vehicle having increased to an upper limit value within said permitted range, and

setting said lower limit value when said vehicle is traveling on the downhill to be higher than that when said vehicle is traveling on the flat road.

21. A vehicle, comprising:

a driving source generating driving power for traveling of said vehicle;

a control device for controlling said driving source; and

an inclination detecting unit for detecting an inclination of a road surface, wherein

said control device executes a driving power change operation that causes said vehicle to travel while switching between a first state of said driving source where first-level driving power is generated and a second state of said driving source where driving power smaller than that in said first state is generated,

when it is recognized that said vehicle is traveling on a downhill, based on the inclination detected by said inclination detecting unit, said control device sets the driving power in said first state to be smaller than that when said vehicle is traveling on a flat road, and

said control device sets the driving power in said second state when said vehicle is traveling on the downhill to be larger than the driving power in said second state when said vehicle is traveling on the flat road.

22. A vehicle, comprising:

a driving source generating driving power for traveling of said vehicle;

a control device for controlling said driving source; and

an inclination detecting unit for detecting an inclination of a road surface, wherein

said control device executes a driving power change operation that causes said vehicle to travel while switching between a first state of said driving source where first-level driving power is generated and a second state of said driving source where driving power smaller than that in said first state is generated,

when it is recognized that said vehicle is traveling on a downhill, based on the inclination detected by said inclination detecting unit, said control device sets the driving power in said first state to be smaller than that when said vehicle is traveling on a flat road,

said driving source is a rotating electric machine, and

when said vehicle is traveling on the downhill, said control device executes a regenerative operation of said rotating electric machine in said second state.