Engine spin-up control with natural torque smoothing

• US 20060166783A1
• Filed: 01/26/2005
• Published: 07/27/2006
• Est. Priority Date: 01/26/2005
• Status: Active Grant

• Current Assignee: GM Global Technology Operations LLC (General Motors Company)
• Original Assignee: GM Global Technology Operations Incorporated (Motors Liquidation Co. GUC Trust)
• Inventors: Tamai, Goro, Hoang, Tony T.
• Granted Patent: US 7,220,217 B2
• Time in Patent Office: Days
• US Class Current: 477/7
• CPC Class Codes: B60K 2006/268 Electric drive motor starts the engine, i.e. used as starter motor
• 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 30/20 Reducing vibrations in the driveline
• CPC Class Codes: F02N 11/14 Starting of engines by means of electric starters with external current supply F02N11/12 takes precedence
• CPC Class Codes: F02N 15/08 the gearing being of friction type
• CPC Class Codes: F02N 2300/104 Control of the starter motor torque
• CPC Class Codes: Y02T 10/62 Hybrid vehicles
• CPC Class Codes: Y02T 10/72 Electric energy management in electromobility

Abstract

A hybrid vehicle includes an engine having at least one cylinder and an electric machine that drives the engine during a start-up period. A control module monitors a rotational speed of the engine and regulates torque generated by the electric machine based on the rotational speed during the start-up period and a maximum discharge power available to power the electric machine.

Claims

1. A hybrid vehicle, comprising:

an engine having at least one cylinder;

an electric machine that drives said engine during a start-up period; and

a control module that monitors a rotational speed of said engine and that regulates torque generated by said electric machine based on said rotational speed and a maximum discharge power available to power said electric machine during said start-up period.

2. The hybrid vehicle of claim 1 further comprising a driver input device, wherein said control module determines said maximum discharge power based on said driver input device.

3. The hybrid vehicle of claim 2 wherein said control module determines a start-up schedule based on said driver input device and determines said maximum power based on said start-up schedule.

4. The hybrid vehicle of claim 3 wherein said start-up schedule includes a torque command and said maximum discharge power.

5. The hybrid vehicle of claim 4 wherein said start-up schedule further includes a torque slew rate command.

6. The hybrid vehicle of claim 2 wherein said driver input device includes an accelerator pedal.

7. The hybrid vehicle of claim 6 wherein said control module determines a start-up schedule based on a position of said accelerator pedal.

8. The hybrid vehicle of claim 2 wherein said driver input device includes a brake pedal.

9. The hybrid vehicle of claim 8 wherein said control module determines a start-up schedule based on a position of said brake pedal.

10. The hybrid vehicle of claim 2 wherein said control module determines said start-up schedule based on a pressure within a brake system.

11. The hybrid vehicle of claim 1 wherein said control module regulates said rotational speed based upon a desired idle speed when said rotational speed achieves a speed threshold.

12. A method of launching a hybrid vehicle from rest, comprising:

monitoring a driver input from a drive input device;

determining a start-up schedule based on said driver input;

determining a maximum discharge power from said start-up schedule; and

regulating a torque generated by an electric machine to drive an engine during a start-up period based on said maximum discharge power and a rotational speed of said engine.

13. The method of claim 12 wherein said driver input device includes an accelerator pedal and said start-up schedule is determined based on a position of said accelerator pedal.

14. The method of claim 12 wherein said driver input device includes a brake pedal and said start-up schedule is determined based on a position of said brake pedal.

15. The method of claim 14 wherein said start-up schedule is determined based on a pressure within a brake system.

16. The method of claim 12 further comprising regulating said rotational speed based upon a desired idle speed when said rotational speed achieves a speed threshold.

17. The method of claim 12 wherein said maximum discharge power is determined from said start-up schedule based on a rotational speed of said electric machine.

18. The method of claim 17 wherein said maximum discharge power is further determined from said start-up schedule based on a rate of change of said rotational speed.

19. The method of claim 12 further comprising activating a cylinder of said engine subsequent to said engine achieving an idle speed.

20. A method of spinning up an engine of a hybrid vehicle to an idle speed during a start-up period, comprising:

determining a start-up schedule including a maximum discharge power; and

regulating a torque generated by an electric machine to drive said engine during said start-up period based on said maximum discharge power and a rotational speed of said engine.

21. The method of claim 20 further comprising:

monitoring a driver input from a driver input device; and

determining said start-up schedule based on said driver input.

22. The method of claim 21 wherein said driver input device includes an accelerator pedal and said start-up schedule is determined based on a position of said accelerator pedal.

23. The method of claim 21 wherein said driver input device includes a brake pedal and said start-up schedule is determined based on a position of said brake pedal.

24. The method of claim 23 wherein said start-up schedule is determined based on a pressure within a brake system.

25. The method of claim 20 further comprising regulating said rotational speed based upon a desired idle speed profile when said rotational speed achieves a speed threshold.

26. The method of claim 20 wherein said maximum discharge power is determined from said start-up schedule based on a rotational speed of said electric machine.

27. The method of claim 26 wherein said maximum discharge power is further determined from said start-up schedule based on a rate of change of said rotational speed.

28. The method of claim 20 further comprising activating a cylinder of said engine subsequent to said engine achieving an idle speed.