METHOD FOR OPERATING A HYBRID ELECTRIC POWERTRAIN BASED ON PREDICTIVE EFFECTS UPON AN ELECTRICAL ENERGY STORAGE DEVICE

• US 20070284162A1
• Filed: 06/07/2006
• Published: 12/13/2007
• Est. Priority Date: 06/07/2006
• Status: Active Grant

• Current Assignee: GM Global Technology Operations LLC (General Motors Company)
• Original Assignee: GM Global Technology Operations LLC (General Motors Company)
• Inventors: Zettel, Andrew M., Heap, Anthony H.
• Granted Patent: US 8,091,667 B2
• Time in Patent Office: Days
• US Class Current: 180/65.290
• CPC Class Codes: B60K 6/448 Electrical distribution type
• CPC Class Codes: B60W 10/08 including control of electric propulsion units, e.g. motors or generators
• 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 20/15 Control strategies specially adapted for achieving a particular effect
• CPC Class Codes: Y02T 10/62 Hybrid vehicles
• CPC Class Codes: Y10S 903/907 Electricity storage, e.g. battery, capacitor

Abstract

A hybrid electric powertrain includes an electrical energy storage device and electric machines. A method for operating the powertrain is disclosed to control the electric machines effective to attain a predetermined state of life profile for the electric energy storage device.

Claims

1. Method for operating a hybrid electric powertrain including an electrical energy storage device adapted for exchanging electrical energy with a hybrid vehicular powertrain including first and second electric machines, each machine operable to impart torque to a two-mode, compound-split electro-mechanical transmission having four fixed gear ratios and two continuously variable operating modes, comprising:

establishing a plurality of values for current of the electrical energy storage device during periods of vehicle activity;

for each respective value, determining a corresponding change in state of life for the energy storage device based upon said respective value; and

operating the electric machines based on the determined changes in state of life.

2. The method of claim 1 wherein operating the electric machines based on the determined changes in state of life comprises operating the electric machines to effect a predetermined state of life profile.

3. The method of claim 2 wherein operating the electric machines to effect a predetermined state of life profile comprises limiting allowable electric machine currents in accordance with the determined changes in state of life and predetermined state of life profile.

4. The method of claim 2 wherein operating the electric machines to effect a predetermined state of life profile comprises establishing electric machine currents in accordance with the determined changes in state of life and predetermined state of life profile.

5. The method of claim 1 wherein change in the state of life is determined based upon an integration of electrical current, a depth of discharge of the energy storage device, and, an operating temperature factor of the electrical energy storage device.

6. The method of claim 5 wherein the depth of discharge of the electrical energy storage device is determined based upon the electrical current.

7. The method of claim 5 wherein the operating temperature factor of the electrical energy storage device is determined based upon the electrical current and temperature of the electrical energy storage device.

8. Method for operating a hybrid electric powertrain including an electrical energy storage device adapted for exchanging electrical energy with a hybrid vehicular powertrain including first and second electric machines, each machine operable to impart torque to a two-mode, compound-split electro-mechanical transmission having four fixed gear ratios and two continuously variable operating modes, comprising:

providing a plurality of potential currents for the electrical energy storage device during periods of vehicle activity;

for each potential current, predicting a respective effect upon electrical energy storage device state of life; and

operating the electric machines based on the predicted effects upon electrical energy storage device state of life.

9. The method of claim 8 wherein operating the electric machines based on the predicted effects upon electrical energy storage device state of life comprises operating the electric machines to effect a predetermined state of life profile.

10. The method of claim 9 wherein operating the electric machines to effect a predetermined state of life profile comprises limiting allowable electric machine currents in accordance with the predicted effects upon electrical energy storage device state of life and predetermined state of life profile.

11. The method of claim 9 wherein operating the electric machines to effect a predetermined state of life profile comprises establishing electric machine currents in accordance with the predicted effects upon electrical energy storage device state of life and predetermined state of life profile.

12. The method of claim 8 wherein predicting effects upon electrical energy storage device state of life comprises predicting changes in the state of life based on a plurality of factors affected by electrical energy storage device current.

13. The method of claim 12 wherein said plurality of factors affected by electrical energy storage device current comprises a factor related to current integration over time.

14. The method of claim 12 wherein said plurality of factors affected by electrical energy storage device current comprises a factor related to depth of discharge of the electrical energy storage device.

15. The method of claim 12 wherein said plurality of factors affected by electrical energy storage device current comprises a factor related to temperature of the electrical energy storage device.

18. The method of claim 9 wherein establishing electric machine current comprises establishing electric machine current in accordance with the predicted effects upon electrical energy storage device state of life and the target profile.

19. The method of claim 12 wherein said plurality of factors affected by electrical energy storage device current comprises a factor related to current integration over time, a factor related to depth of discharge of the electrical energy storage device and a factor related to temperature of the electrical energy storage device.

16. Method for operating a hybrid electric powertrain including an electrical energy storage device adapted for exchanging electrical energy with a hybrid vehicular powertrain including first and second electric machines, each machine operable to impart torque to a two-mode, compound-split electro-mechanical transmission having four fixed gear ratios and two continuously variable operating modes, comprising:

providing a plurality of predicted effects upon electrical energy storage device state of life based on a plurality of potential electrical energy storage device currents during periods of vehicle activity;

providing a target profile for electrical energy storage device state of life; and

establishing electric machine current based on the predicted effects and target profile.

17. The method of claim 16 wherein establishing electric machine current comprises limiting allowable electric machine current in accordance with the predicted effects upon electrical energy storage device state of life and the target profile.