Method for controlling the operating characteristics of a hybrid electric vehicle

• US 6,847,189 B2
• Filed: 06/24/2003
• Issued: 01/25/2005
• Est. Priority Date: 05/31/1995
• Status: Expired due to Fees

• 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.
• Primary Examiner(s): TIBBITS, PIA FLORENCE
• Application Number:
  US10/606,128
• Publication Number:
  US 20040060751A1
• Time in Patent Office: 581 Days
• Field of Search: 320/104, 180 652- 654, 180/65.6, 180/65.8, 180/165, 607/16, 607/18, 607/06, 607/11, 290/17, 290/4.R, 290/4.C, 322/16
• US Class Current: 320/104
• 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 a internal combustion engine, an electric motor, and a battery system and controller for powering the electric motor, the improvement comprising:

providing a transmission between said electric motor and a set of wheels in said vehicle; and

controlling interaction between the internal combustion engine, the electric motor and the transmission to regenerate energy into the battery system only if engine fuel efficiency during regeneration and during subsequent power production from the electric motor is greater than engine fuel efficiency resulting from throttling the engine to reduce engine/motor power.

4. An improvement as recited in claim 1, wherein said transmission comprises a multispeed transmission.

5. An improvement as recited in claim 1, wherein said transmission comprises a continuously variable transmission.

2. A method for controlling the power output of an internal combustion engine and electric motor operated by a battery system and controller in a hybrid electric vehicle, comprising:

providing a transmission between said electric motor and a set of wheels in said vehicle; and

controlling interaction between the internal combustion engine, the electric motor and the transmission to regenerate energy into the battery system only if engine fuel efficiency during regeneration and during subsequent power production from the electric motor is greater than engine fuel efficiency resulting from throttling the engine to reduce engine/motor power.

6. A method as recited in claim 2, wherein said transmission comprises a multispeed transmission.

7. A method as recited in claim 2, wherein said transmission comprises a continuously variable transmission.

3. An apparatus for controlling the power output of an internal combustion engine and electric motor operated by a battery system and controller in a hybrid electric vehicle, comprising:

a computer; and

programming associated with said computer for controlling interaction between the internal combustion engine, the electric motor and a transmission between the electric motor and a set of wheels in the vehicle to regenerate energy into the battery system only if engine fuel efficiency during regeneration and during subsequent power production from the electric motor is greater than engine fuel efficiency resulting from throttling the engine to reduce engine/motor power.

8. An apparatus as recited in claim 3, wherein said transmission comprises a multispeed transmission.

9. An apparatus as recited in claim 3, wherein said transmission comprises a continuously variable transmission.