Method for controlling the operating characteristics of a hybrid electric vehicle

• US 20040060751A1
• Filed: 06/24/2003
• Published: 04/01/2004
• Est. Priority Date: 05/31/1995
• Status: Active Grant

• Current Assignee: Regents of the University of California (University of California)
• Original Assignee: Regents of the University of California (University of California)
• Inventors: Frank, Andrew A.
• Granted Patent: US 6,847,189 B2
• Time in Patent Office: Days
• US Class Current: 180/65.2
• CPC Class Codes: B60K 26/02 of initiating means or elements
• CPC Class Codes: B60K 6/48 Parallel type
• CPC Class Codes: B60K 6/54 Transmission for changing ratio
• CPC Class Codes: B60K 6/543 the transmission being a continuously variable transmission
• CPC Class Codes: B60L 15/2045 for optimising the use of energy
• CPC Class Codes: B60L 2260/26 Transition between different drive modes
• CPC Class Codes: B60L 50/16 with provision for separate direct mechanical propulsion
• CPC Class Codes: B60L 50/61 by batteries charged by engine-driven generators, e.g. series hybrid electric vehicles
• CPC Class Codes: B60L 58/12 responding to state of charge [SoC]
• CPC Class Codes: B60T 13/586 the retarders being of the electric type
• CPC Class Codes: B60T 7/042 by electrical means, e.g. using travel or force sensors
• CPC Class Codes: B60W 10/02 including control of driveline clutches
• CPC Class Codes: B60W 10/06 including control of combustion engines
• CPC Class Codes: B60W 10/08 including control of electric propulsion units, e.g. motors or generators
• CPC Class Codes: B60W 10/10 including control of change-speed gearings
• CPC Class Codes: B60W 10/107 with endless flexible members
• CPC Class Codes: B60W 10/26 for electrical energy, e.g. batteries or capacitors
• 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 20/10 Controlling the power contribution of each of the prime movers to meet required power demand
• CPC Class Codes: B60W 2510/244 Charge state
• CPC Class Codes: B60W 2520/10 : Longitudinal speed
• CPC Class Codes: B60W 2540/10 : Accelerator pedal position
• CPC Class Codes: B60W 2540/12 : Brake pedal position
• CPC Class Codes: B60W 2710/0677 : Engine power
• CPC Class Codes: F16H 61/66 : specially adapted for continuously variable gearings control of exclusively fluid gearing F16H61/38
• CPC Class Codes: F16H 61/66254 : controlling of shifting being influenced by a signal derived from the engine and the main coupling
• CPC Class Codes: H02J 2310/48 : for electric vehicles [EV] or hybrid vehicles [HEV]
• CPC Class Codes: H02J 7/1446 : in response to parameters of a vehicle
• 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: Y10S 903/903 : having energy storing means, e.g. battery, capacitor
• CPC Class Codes: Y10S 903/916 : with plurality of drive axles
• CPC Class Codes: Y10S 903/917 : with transmission for changing gear ratio
• CPC Class Codes: Y10S 903/918 : Continuously variable
• CPC Class Codes: Y10S 903/945 : Characterized by control of gearing, e.g. control of transmission ratio
• CPC Class Codes: Y10S 903/946 : Characterized by control of driveline clutch

Abstract

A control method for operating internal combustion engine electric hybrid vehicles with smaller battery packs, particularly in configurations where an electric motor (E/M) or electric motor/generator (E/MG), a battery, and associated controls are inserted between the engine and a continuously variable or automatic transmission. The interaction between the combustion engine and battery operated electric motor is controlled by taking energy into the batteries only if it is more efficient than throttling the engine and operating the engine at a lower efficiency. Additionally, the batteries are charged to a certain state or the batteries are maintained at a particular state of charge. A goal of the invention is to obtain the best possible fuel economy while maintaining good driveability.

Claims

1. In a hybrid electric vehicle having an internal combustion engine, an electric motor, and a battery system for powering the electric motor, the improvement comprising:

controlling the interaction between the internal combustion engine and electric motor by taking energy into the battery system only if it is more fuel efficient than throttling the engine and operating the engine at a lower efficiency.

2. An improvement as recited in claim 1, further comprising:

charging the battery system to a certain state or maintaining the battery system at a particular state of charge during operation of the vehicle.

3. A method for controlling the interaction between an internal combustion engine and electric motor operated by a battery system in a hybrid electric vehicle, comprising:

taking energy into the battery system only if it is more fuel efficient than throttling the engine and operating the engine at a lower efficiency.

4. A method as recited in claim 3, further comprising:

charging the battery system to a certain state or maintaining the battery system at a particular state of charge during operation of the vehicle.

5. An apparatus for controlling the interaction between an internal combustion engine and electric motor operated by a battery system in a hybrid electric vehicle, comprising:

a computer; and

programming associated with said computer for taking energy into the battery system only if it is more fuel efficient than throttling the engine and operating the engine at a lower efficiency.

6. An apparatus as recited in claim 5, further comprising:

programming associated with said computer for charging the battery system to a certain state or maintaining the battery system at a particular state of charge during operation of the vehicle.

7. In a hybrid electric vehicle having an internal combustion engine, an electric motor, and a battery system for powering the electric motor, the improvement comprising:

using engine “

turn-on”

speed to regulate depth of discharge of the battery system by observing average depth of discharge of the battery system over a period of time and maintaining the depth of discharge between a maximum and minimum with the engine.

8. A battery control method for an hybrid electric vehicle having an internal combustion engine, an electric motor, and a battery system for powering the electric motor, comprising:

using engine “

turn-on”

speed to regulate depth of discharge of the battery system by observing average depth of discharge of the battery system over a period of time and maintaining the depth of discharge between a maximum and minimum with the engine.

9. A battery control apparatus for a hybrid electric vehicle having an internal combustion engine, an electric motor, and a battery system for powering the electric motor, comprising:

a computer; and

programming associated with said computer for using the engine “

turn-on”

speed to regulate the depth of discharge of the battery system by observing average depth of discharge of the battery system over a period of time and maintaining the depth of discharge between a maximum and minimum with the engine.

10. In a hybrid electric vehicle having an internal combustion engine, an electric motor, and a battery system for powering the electric motor, the improvement comprising:

cycling depth of discharge of the battery system with the engine to maintain the depth of discharge between a maximum and minimum.

11. A battery control method for a hybrid electric vehicle having an internal combustion engine, an electric motor, and a battery system for powering the electric motor, comprising:

cycling depth of discharge of the battery system with the engine to maintain the depth of discharge between a maximum and minimum.

12. A battery control apparatus method for a hybrid electric vehicle having an internal combustion engine, an electric motor, and a battery system for powering the electric motor, comprising:

a computer; and

programming associated with said computer for cycling depth of discharge of the battery system with the engine to maintain the depth of discharge between a maximum and minimum.

13. In a hybrid electric vehicle having an internal combustion engine, an electric motor, and a battery system for powering the electric motor, the improvement comprising:

setting a closed loop system to regulate depth discharge of the battery system with a frequency bandwidth sufficient to meet predetermined operating criteria;

said predetermined operating criteria selected from the group consisting essentially of battery life, vehicle range, and driveability.

14. An improvement as recited in claim 13, further comprising:

regulating depth of discharge of the battery system without fully charging the battery system with the engine.

15. A battery control method for a hybrid electric vehicle having an internal combustion engine, an electric motor, and a battery system for powering the electric motor, comprising:

setting a closed loop system to regulate depth discharge of the battery system with a frequency bandwidth sufficient to meet predetermined operating criteria;

said predetermined operating criteria selected from the group consisting essentially of battery life, vehicle range, and driveability.

16. A method as recited in claim 15, further comprising:

regulating depth of discharge of the battery system without fully charging the battery system with the engine.

17. A battery control apparatus for a hybrid electric vehicle having an internal combustion engine, an electric motor, and a battery system for powering the electric motor, comprising:

a closed loop system configured to regulate depth discharge of the battery system with a frequency bandwidth sufficient to meet predetermined operating criteria;

said predetermined operating criteria selected from the group consisting essentially of battery life, vehicle range, and driveability.

18. An apparatus as recited in claim 17, further comprising:

a computer; and

programming associated with said computer for regulating depth of discharge of the battery system without fully charging the battery system with the engine.

19. In a hybrid electric vehicle having an internal combustion engine, an electric motor, and a battery system for powering the electric motor, the improvement comprising:

using vehicle speed as a determinant of vehicle energy demand from said battery system.

20. A battery control method for an hybrid electric vehicle having an internal combustion engine, an electric motor, and a battery system for powering the electric motor, comprising:

using vehicle speed as a determinant of vehicle energy demand from said battery system.

21. A battery control apparatus for a hybrid electric vehicle having an internal combustion engine, an electric motor, and a battery system for powering the electric motor, comprising:

a computer; and

programming associated with said computer for using vehicle speed as a determinant of vehicle energy demand from said battery system.

22. In a hybrid electric vehicle having an internal combustion engine, an electric motor, a battery system for powering the electric motor, and a continuously variable transmission (CVT) powertrain system, the improvement comprising:

using the electric motor and battery system to provide acceleration and deceleration compensation for the CVT powertrain system dynamics.

23. A control method for a hybrid electric vehicle having an internal combustion engine, an electric motor, a battery system for powering the electric motor, and a continuously variable transmission (CVT) powertrain system, comprising:

using the electric motor and battery system to provide acceleration and deceleration compensation for the CVT powertrain system dynamics.

24. A control apparatus for a hybrid electric vehicle having an internal combustion engine, an electric motor, a battery system for powering the electric motor, and a continuously variable transmission (CVT) powertrain system, comprising:

a computer; and

programming associated with said computer for using the electric motor and battery system to provide acceleration and deceleration compensation for the CVT powertrain system dynamics.