Method for controlling a hybrid electric vehicle

• US 7,206,687 B1
• Filed: 04/06/2006
• Issued: 04/17/2007
• Est. Priority Date: 04/06/2006
• Status: Active Grant

• Current Assignee: GM Global Technology Operations LLC (General Motors Company)
• Original Assignee: General Motors Corporation (General Motors Company)
• Inventors: Huseman, Steven C.
• Primary Examiner(s): Vo; Hieu T.
• Application Number:
  US11/399,236
• Time in Patent Office: 376 Days
• Field of Search: 701/102, 701/101, 701/115, 701/114, 701/22, 180/65.2, 180/65.4, 731/173, 290/40.A, 290/40.C, 290/51
• US Class Current: 701/102
• CPC Class Codes: B60K 6/48 Parallel type
• 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 20/00 Control systems specially adapted for hybrid vehicles hybrid vehicle design, B60K6/00; electric vehicles B60L
• CPC Class Codes: B60W 20/13 in order to stay within battery power input or output limits; in order to prevent overcharging or battery depletion
• CPC Class Codes: B60W 2540/10 Accelerator pedal position
• CPC Class Codes: B60W 2710/086 Power
• CPC Class Codes: B60W 50/087 where the control system corrects or modifies a request from the driver
• CPC Class Codes: Y02T 10/40 Engine management systems
• CPC Class Codes: Y02T 10/62 Hybrid vehicles
• CPC Class Codes: Y02T 10/84 Data processing systems or methods, management, administration
• CPC Class Codes: Y10S 903/93 Conjoint control of different elements

Abstract

The present invention provides a method adapted to control a hybrid electric vehicle having a primary power source and a secondary power source. The method includes estimating the power capability of the primary power source, and thereafter obtaining a power command from the vehicle'"'"'s driver. A primary power demand and a secondary power demand which collectively meet the driver power command are then established, and a desired power balance between the primary power demand and the secondary power demand is also obtained. A system power capability is calculated based on the desired power balance and the estimated power capability. The method of the present invention then determines if the driver power command exceeds the system power capability. If the driver power command exceeds the system power capability, the driver power command limited and thereafter the limited driver power command is executed.

Claims

1. A method for controlling a hybrid electric vehicle having a primary power source and a secondary power source comprising:

estimating the power capability of the primary power source;

obtaining a driver power command;

establishing a primary power demand for the primary power source, a secondary power demand for the secondary power source, and a desired power balance between the primary power demand and the secondary power demand;

calculating a system power capability based on the desired power balance and the estimated power capability of the primary power source;

determining if the driver power command exceeds the system power capability;

limiting the driver power command if the driver power command exceeds the system power capability; and

executing the limited driver power command.

2. The method of claim 1, wherein said obtaining a driver power command includes monitoring the position of a gas pedal, and implementing a throttle lookup table.

3. The method of claim 1, wherein said establishing a primary power demand and a secondary power demand includes establishing a primary power demand and secondary power demand which collectively meet the driver power command in an optimally fuel efficient manner.

4. The method of claim 1, further comprising executing the driver power command if the driver power command does not exceed the system power capability.

5. The method of claim 1, wherein the primary power source is an engine.

6. The method of claim 5, wherein the secondary power source is an electric motor/generator.

7. A method for controlling a hybrid electric vehicle having a primary power source and a secondary power source comprising:

estimating the power capability of the primary power source;

obtaining a driver power command;

establishing a primary power demand for the primary power source and secondary power demand for the secondary power source which collectively meet the driver power command;

establishing a desired power balance between the primary power demand and the secondary power demand;

calculating a system power capability based on the desired power balance and the estimated power capability of the primary power source;

determining if the driver power command exceeds the system power capability;

executing the driver power command if the driver power command does not exceed the system power capability;

limiting the driver power command if the driver power command exceeds the system power capability; and

executing the limited driver power command if the driver power command exceeds the system power capability.

8. The method of claim 7, wherein said obtaining a driver power command includes monitoring the position of a gas pedal, and implementing a throttle lookup table.

9. The method of claim 7, wherein the primary power source is an engine.

10. The method of claim 9, wherein the secondary power source is an electric motor/generator.

11. A method for controlling a hybrid electric vehicle having an engine and an electric motor/generator comprising:

estimating the power capability of the engine;

monitoring the position of a gas pedal and implementing a throttle lookup table to obtain a driver power command;

establishing an engine power demand for the engine and a motor/generator power demand for the motor/generator which collectively meet the driver power command;

establishing a desired power balance between the engine power demand and the motor/generator power demand;

calculating a system power capability based on the desired power balance and the estimated power capability of the engine;

determining if the driver power command exceeds the system power capability;

executing the driver power command if the driver power command does not exceed the system power capability;

limiting the driver power command if the driver power command exceeds the system power capability; and

executing the limited driver power command if the driver power command exceeds the system power capability.