LEARNED EGR VALVE POSITION CONTROL

• US 20070043498A1
• Filed: 08/19/2005
• Published: 02/22/2007
• Est. Priority Date: 08/19/2005
• 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: McLain, Kurt
• Granted Patent: US 7,198,038 B2
• Time in Patent Office: Days
• US Class Current: 701/108
• CPC Class Codes: F02D 41/0077 Control of the EGR valve or actuator, e.g. duty cycle, closed loop control of position EGR valve position sensor F02M26/48
• CPC Class Codes: F02D 41/2464 Characteristics of actuators
• CPC Class Codes: F02M 26/48 EGR valve position sensors details of the sensor installation in the valve housing F02M26/72
• CPC Class Codes: F02M 26/49 Detecting, diagnosing or indicating an abnormal function of the EGR system
• CPC Class Codes: Y02T 10/40 Engine management systems

Abstract

An exhaust gas recirculation (EGR) valve positioning system according to the present invention includes an actuate valve module, an EGR valve position module, and an adjust control variables module. The actuate valve module selectively uses learned and default variables as control variables to position an EGR valve. The EGR valve position module determines whether the EGR valve is positioned in a target position. The adjust control variables module communicates with the actuate valve module and the EGR valve position module and adjusts the learned variables when the EGR valve position module determines that the EGR valve is positioned out of the target position.

Claims

1. An exhaust gas recirculation (EGR) valve positioning system, comprising:

an actuate valve module that selectively uses learned and default variables as control variables to position an EGR valve;

an EGR valve position module that determines whether said EGR valve is positioned in a target position based on a position sensor signal; and

an adjust control variables module that communicates with said actuate valve module and said EGR valve position module and that adjusts said learned variables when said EGR valve position module determines that said EGR valve is positioned out of said target position.

2. The EGR valve positioning system of claim 1 wherein said default variables are used as said control variables when said EGR valve positioning system is running for a first time.

3. The EGR valve positioning system of claim 2 wherein said learned variables are used as said control variables when said EGR valve positioning system is running after said first time.

4. The EGR valve positioning system of claim 3 wherein said learned variables are stored when said EGR valve positioning module determines that said EGR valve is positioned in said target position.

5. The EGR valve positioning system of claim 1 wherein said learned variables are adjusted by incrementally moving said EGR valve toward said target position.

6. The EGR valve positioning system of claim 4 further comprising an EGR valve position sensor that communicates the position of said EGR valve to said EGR valve position module.

7. The EGR valve positioning system of claim 1 wherein said control variables comprise a magnitude of current and a period of time in which said magnitude of current is provided.

8. A method of positioning an exhaust gas recirculation (EGR) valve, comprising:

selectively using learned and default variables as control variables to position the EGR valve;

determining whether the position of the EGR valve is in a target position based on a position sensor signal; and

adjusting said learned variables when the EGR valve is positioned out of said target position.

9. The method of claim 8 wherein said default variables are used as said control variables when the EGR valve is positioned for a first time.

10. The method of claim 9 wherein said learned variables are used as said control variables when the EGR valve is positioned after said first time.

11. The method of claim 10 wherein said learned variables are stored when the EGR valve is positioned in said target position.

12. The method of claim 8 wherein said learned variables are adjusted by incrementally moving the EGR valve toward said target position.

13. A method of positioning an exhaust gas recirculation (EGR) valve during a flow restriction test comprising:

determining whether conditions have been met to enable the flow restriction test;

selectively using learned and default variables as control variables to position the EGR valve if said conditions have been met to enable the flow restriction test;

determining whether the position of the EGR valve is in a target position based on a position sensor signal; and

adjusting said learned variables when the EGR valve is positioned out of said target position.

14. The method of claim 13 wherein said default variables are used as said control variables when the EGR valve is positioned for a first time.

15. The method of claim 14 wherein said learned variables are used as said control variables when the EGR valve is positioned after said first time.

16. The method of claim 15 wherein said learned variables are stored when the EGR valve is positioned in said target position.

17. The method of claim 13 wherein said learned variables are adjusted by incrementally moving the EGR valve toward said target position.