Fuel-cut manifold absolute pressure control

• US 7,757,665 B2
• Filed: 08/07/2007
• Issued: 07/20/2010
• Est. Priority Date: 08/25/2006
• 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, Worthing, James L.
• Primary Examiner(s): KWON, JOHN
• Application Number:
  US11/890,765
• Publication Number:
  US 20080047524A1
• Time in Patent Office: 1,078 Days
• Field of Search: 123/198.F, 123/332, 123/481, 123/493, 701/103, 701/104, 701/110, 701/112
• US Class Current: 123/481
• CPC Class Codes: B60L 2240/441 Speed
• CPC Class Codes: B60W 10/06 including control of combustion engines
• 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: B60W 2510/0638 Engine speed
• CPC Class Codes: B60W 2510/0671 Engine manifold pressure
• CPC Class Codes: B60W 2540/10 Accelerator pedal position
• CPC Class Codes: B60W 2540/12 Brake pedal position
• CPC Class Codes: B60W 2710/0605 Throttle position
• CPC Class Codes: F02D 2041/0012 with selective deactivation of cylinders
• CPC Class Codes: F02D 41/0005 during deceleration
• CPC Class Codes: F02D 41/123 the fuel injection being cut-off
• CPC Class Codes: Y02T 10/40 Engine management systems

Abstract

A method of regulating a throttle opening of an engine in a hybrid electric vehicle system includes initiating a fuel-cut off operating mode of the engine, monitoring an engine speed during said fuel cut-off operating mode and regulating the throttle opening based on the engine speed during the fuel-cut off mode to maintain a manifold absolute pressure (MAP) of the engine above a threshold MAP.

Claims

1. A method of regulating a throttle opening of an engine in a hybrid electric vehicle system, comprising:

initiating a fuel-cut off operating mode of the engine;

monitoring an engine speed;

regulating the throttle opening based on said engine speed during said fuel-cut off mode; and

maintaining a manifold absolute pressure (MAP) of said engine above a threshold MAP during said fuel-cut off mode.

2. The method of claim 1 further comprising:

determining a throttle area offset based on said engine speed; and

determining a base throttle area, wherein said regulating of said throttle opening is achieved based on said throttle area offset and said base throttle area.

3. The method of claim 2 wherein said throttle area offset is determined from a look-up table.

4. The method of claim 1 further comprising:

determining a minimum MAP based on said engine speed; and

determining a base throttle area based on said minimum MAP.

5. The method of claim 1 further comprising:

determining a minimum MAP based on said engine speed; and

determining a desired torque based on said minimum MAP.

6. A throttle regulation system of an engine in a hybrid electric vehicle system, comprising:

a first module that initiates a fuel-cut off operating mode of the engine;

a second module that monitors an engine speed;

a third module that regulates a throttle opening based on said engine speed during said fuel-cut off mode, wherein said third module maintains a manifold absolute pressure (MAP) of said engine above a threshold MAP during said fuel-cut off mode.

7. The throttle regulation system of claim 6 further comprising:

a fourth module that determines a throttle area offset based on said engine speed, wherein said fourth module determines a base throttle area, and wherein regulating of said throttle opening is achieved based on said throttle area offset and said base throttle area.

8. The throttle regulation system of claim 7 wherein said throttle area offset is determined from a look-up table.

9. The throttle regulation system of claim 6 further comprising:

a fourth module that determines a minimum MAP based on said engine speed and that determines a base throttle area based on said minimum MAP.

10. The throttle regulation system of claim 9 further comprising:

a fourth module that determines a minimum MAP based on said engine speed and that determines a desired torque based on said minimum MAP.

11. A method of regulating a throttle of an engine in a hybrid electric vehicle system, comprising:

initiating a fuel-cut off operating mode of the engine;

determining one of a desired torque and a base throttle area;

regulating a throttle opening based on said one of said desired torque and said base throttle area during said fuel-cut off mode; and

maintaining a manifold absolute pressure (MAP) of said engine above a threshold MAP during said fuel-cut off mode.

12. The method of claim 11 further comprising:

determining a throttle area offset based on said engine speed; and

determining said base throttle area, wherein said regulating of said throttle opening is achieved based on said throttle area offset and said base throttle area.

13. The method of claim 12 wherein said throttle area offset is determined from a look-up table.

14. The method of claim 11 further comprising:

determining a minimum MAP based on an engine speed; and

determining said base throttle area based on said minimum MAP.

15. The method of claim 11 further comprising:

determining a minimum MAP based on an engine speed; and

determining said desired torque based on said minimum MAP.