METHOD AND APPARATUS FOR DETERMINING TEMPERATURE IN A GAS FEEDSTREAM

• US 20110038394A1
• Filed: 10/22/2010
• Published: 02/17/2011
• Est. Priority Date: 09/11/2007
• 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: Kalweit, Nicholas John, Verdejo, Julian R., Ma, Qi
• Granted Patent: US 8,152,369 B2
• Time in Patent Office: Days
• US Class Current: 374/148
• CPC Class Codes: F02D 2041/1416 Observer
• CPC Class Codes: F02D 41/1446 the characteristics being exhaust temperatures
• CPC Class Codes: F02D 41/1447 with determination means using an estimation
• CPC Class Codes: F02D 41/1494 Control of sensor heater
• CPC Class Codes: G01K 13/02 for measuring temperature of moving fluids or granular materials capable of flow
• CPC Class Codes: G01K 2205/04 for measuring exhaust gas temperature

Abstract

An internal combustion engine includes an exhaust gas feedstream flowing past a gas sensing device disposed therein. The gas sensor includes an integrated electrical heating element which provides a resistance indicative of its temperature. An unknown input observer is used to determine the exhaust gas feedstream temperature based on the heating element temperature.

Claims

1. Method for measuring a gas feedstream temperature, comprising:

providing a gas sensing device including an integrated heating element disposed within the gas feedstream;

measuring electrical resistance of the integrated heating element;

determining temperature of the integrated heating element based upon the measured electrical resistance;

determining a gas temperature proximal to the sensing device based upon the temperature of the integrated heating element; and

,

determining the gas feedstream temperature based upon the gas temperature proximal to the sensing device.

2. The method of claim 1, wherein determining a gas temperature proximal to the sensing device comprises estimating the gas temperature proximal to the sensing device with an unknown input observer model.

3. The method of claim 2, wherein determining a gas temperature proximal to the sensing device comprises estimating the gas temperature of gases within a shielded area of the sensing device.

4. The method of claim 2, wherein the unknown input observer model comprises a linear model.

5. The method of claim 2, wherein the gas feedstream comprises post-combustion process exhaust gases.

6. The method of claim 5, wherein the post-combustion process exhaust gases comprise exhaust gases from an internal combustion engine.

7. Control system for monitoring an exhaust gas feedstream, comprising:

a sensing device having an integrated heating element;

a control module monitoring an electrical resistance of the integrated heating element, determining a temperature of the integrated heating element based upon the electrical resistance, determining a gas temperature proximal to the sensing device based upon the temperature of the integrated heating element, and determining a temperature of the gas feedstream based upon the gas temperature proximal to the sensing device.

8. The control system of claim 7, wherein the control module determining a gas temperature proximal to the sensing device based upon the temperature of the integrated heating element determines the gas temperature using an unknown input observer model.

9. The control system of claim 8, wherein the gas temperature proximal to the sensing device comprises gas temperature within a shield of the sensing device.

10. The control system of claim 8, wherein the unknown input observer model comprises a linear model.

11. The control system of claim 7, the control module determining a temperature of the gas feedstream determines temperature of the gas feedstream at a predetermined location based upon the gas temperature proximal to the gas sensing device.

12. The control system of claim 7, wherein the sensing device having an integrated heating element comprises a planar-type exhaust gas sensing device.

13. The control system of claim 7, wherein the sensing device monitors a partial pressure of oxygen.

14. The control system of claim 7, wherein the sensing device monitors a gas constituent.

15. The control system of claim 7, wherein the sensing device monitors nitrides of oxygen.

16. Control system for monitoring an exhaust gas feedstream within an exhaust gas aftertreatment system, comprising:

an integrated heating element of a sensing device adapted to monitor the exhaust gas feedstream;

a control module monitoring electrical resistance of the integrated heating element of the sensing device, determining a temperature of the integrated heating element based upon the electrical resistance, estimating a gas temperature proximal to the sensing device based upon the temperature of the integrated heating element using an unknown input observer model, and determining a temperature of the exhaust gas feedstream based upon the estimated gas temperature proximal to the sensing device.

17. The control system of claim 16, wherein the control module estimating the gas temperature proximal to the sensing device estimates the gas temperature within a shield of the sensing device.

18. The control system of claim 16, wherein the control module determining the temperature of the exhaust gas feedstream determines a temperature of the exhaust gas feedstream at a predetermined location in the exhaust aftertreatment system.

19. The control system of claim 16, wherein the sensing device having an integrated heating element comprises a planar-type exhaust gas sensing device.

20. The control system of claim 19, wherein the sensing device monitors a partial pressure of oxygen.

21. The control system of claim 19, wherein the sensing device monitors nitrides of oxygen.