Method of compensating a MOS gas sensor, method of manufacturing a MOS gas sensor, MOS gas sensor, and fuel cell system

• US 6,532,792 B2
• Filed: 07/26/2001
• Issued: 03/18/2003
• Est. Priority Date: 07/26/2001
• Status: Expired due to Fees

• Current Assignee: Relion Incorporated (Plug Power Inc.)
• Original Assignee: Avista Laboratories Inc. (Plug Power Inc.)
• Inventors: Fuglevand, William A., Lloyd, Greg A.
• Primary Examiner(s): Larkin, Daniel S.
• Assistant Examiner(s): Politzer, Jay L
• Application Number:
  US09/916,850
• Publication Number:
  US 20030022039A1
• Time in Patent Office: 600 Days
• Field of Search: 73/232, 73/232.1, 73/310.6, 422/98
• US Class Current: 73/23.2
• CPC Class Codes: G01N 27/122 Circuits particularly adapted therefor, e.g. linearising circuits
• CPC Class Codes: G01N 33/0006 Calibrating gas analysers
• CPC Class Codes: H01M 8/0247 characterised by the form characterised by a channel configuration H01M8/0258
• CPC Class Codes: H01M 8/04007 related to heat exchange
• CPC Class Codes: H01M 8/04089 of gaseous reactants
• CPC Class Codes: H01M 8/04097 with recycling of the reactants H01M8/04119, H01M8/04104 take precedence
• CPC Class Codes: H01M 8/0432 Temperature; Ambient temperature
• CPC Class Codes: H01M 8/0444 Concentration; Density H01M8/04492 takes precedence
• CPC Class Codes: H01M 8/0447 of cathode exhausts
• CPC Class Codes: H01M 8/04522 of cathode exhausts
• CPC Class Codes: H01M 8/04679 of fuel cell stacks
• CPC Class Codes: H01M 8/04955 Shut-off or shut-down of fuel cells
• CPC Class Codes: H01M 8/1004 characterised by membrane-electrode assemblies [MEA] H01M8/12 takes precedence
• CPC Class Codes: H01M 8/241 with solid or matrix-supported electrolytes
• CPC Class Codes: H01M 8/247 Arrangements for tightening a stack, for accommodation of a stack in a tank or for assembling different tanks
• CPC Class Codes: Y02E 60/50 Fuel cells
• CPC Class Codes: Y02P 70/50 Manufacturing or production processes characterised by the final manufactured product

Abstract

A method of compensating a MOS gas sensor is described and which includes using a MOS gas sensor to provide a signal indicative of gas concentration of a target gas in an ambient; providing a signal representative of dew point of the ambient; and modifying the signal from the MOS gas sensor using the signal representative of dew point to simultaneously compensate for the effects of both temperature and relative humidity on the MOS gas sensor.

Claims

1. A method of compensating a MOS gas sensor, consisting of:

using only a single MOS gas sensor to provide a signal indicative of gas concentration of a target gas in an ambient;

providing a signal representative of dew point of the ambient; and

modifying the signal from the single MOS gas sensor using the signal representative of dew point to simultaneously compensate for the effects of both temperature and relative humidity on the single MOS gas sensor.

2. A method in accordance with claim 1 wherein modifying the signal from the gas sensor consists of using analog circuitry.

3. A method in accordance with claim 1 wherein modifying the signal from the gas sensor to compensate for the effects of both temperature and relative humidity consists essentially of using analog circuitry.

4. A method in accordance with claim 1 wherein providing a signal representative of dew point consists of measuring dew point.

5. A method in accordance with claim 1 wherein providing a signal representative of dew point consists of measuring dew point using chilled-mirror equipment.

6. A method in accordance with claim 1 wherein providing a signal representative of dew point consists of deriving dew point from temperature and relative humidity signals.

7. A MOS gas sensor system consisting of:

only a single MOS gas sensor configured to provide a signal indicative of gas concentration of a target gas in an ambient; and

compensation circuitry configured to modify the signal from the single MOS gas sensor, using a signal representative of the dew point of the ambient, to simultaneously compensate for the effects of both temperature and relative humidity on the single MOS gas sensor.

8. A MOS gas sensor system in accordance with claim 7 wherein the circuitry configured to modify the signal from the gas sensor consists of analog circuitry.

9. A MOS gas sensor system in accordance with claim 7 wherein the circuitry configured to modify the signal from the gas sensor consists essentially of analog circuitry.

10. A MOS gas sensor system in accordance with claim 7 and further consisting of hardware, coupled to the circuitry, and which is configured to determine dew point.

11. A MOS gas sensor system in accordance with claim 7 and further consisting of chilled-mirror equipment which is configured to provide a signal representative of dew point, and which is coupled to the circuitry.

12. A MOS gas sensor system in accordance with claim 7 and further consisting of:

a temperature sensor configured to provide a signal representative of temperature of the ambient;

a relative humidity sensor configured to provide a signal representative of the relative humidity of the ambient; and

circuitry coupled to the compensation circuitry and which is configured to derive dew point from the temperature and humidity signals.

13. A method of compensating a MOS gas sensor, consisting of:

using only a single MOS gas sensor which provides a signal indicative of gas concentration of a target gas in an ambient;

determining the dew point of the ambient;

determining a compensation factor for the single MOS gas sensor, and wherein the compensation factor is based upon the determined dew point; and

modifying the signal from the single MOS gas sensor using the compensation factor.

14. A method in accordance with claim 13 wherein the MOS gas sensor is of a given design, and wherein determining a compensation factor consists of setting a compensation factor based upon the given design of MOS gas sensor, as well as based on the determined dew point.

15. A method in accordance with claim 13 wherein modifying the signal from the gas sensor consists of using analog circuitry.

16. A method in accordance with claim 13 wherein modifying the signal from the single MOS gas sensor to compensate for the effects of both temperature and relative humidity consists essentially of using analog circuitry.

17. A method in accordance with claim 13 wherein determining dew point consists of measuring dew point.

18. A method in accordance with claim 13 wherein determining dew point consists of measuring dew point using chilled-mirror equipment.

19. A method in accordance with claim 13 wherein determining dew point consists of measuring temperature and relative humidity and deriving dew point from the measured temperature and relative humidity.

20. A MOS gas sensor system consisting of;

only a single MOS gas sensor configured to provide a signal indicative of gas concentration of a target gas in an ambient;

equipment configured to determine the dew point of the ambient; and

compensation circuitry configured to modify the signal from the single MOS gas sensor using a compensation factor, the compensation factor being selected based upon the determined dew point.

21. A MOS gas sensor system in accordance with claim 20 wherein the single MOS gas sensor is of a given design, and wherein the compensation factor is set based upon the given design, as well as based upon the determined dew point.

22. A MOS gas sensor system in accordance with claim 20 wherein the compensation circuitry consists of analog circuitry.

23. A MOS gas sensor system in accordance with claim 20 wherein the compensation circuitry consists essentially of analog circuitry.

24. A MOS gas sensor system in accordance with claim 20 wherein the equipment configured to determine the dew point of the ambient consists of chilled-mirror equipment.

25. A MOS gas sensor system in accordance with claim 20 wherein the equipment configured to determine the dew point of the ambient consists of a temperature sensor which, in operation, provides a signal representative of temperature of the ambient, a relative humidity sensor which, in operation, provides a signal representative of the relative humidity of the ambient, and circuitry coupled to the compensation circuitry, which, in operation, derives dew point from the temperature and humidity, signals.