Systems and methods for detecting leaks in a fuel cell system

Patent metadata

Field	Value
Publication number	US-2016197366-A1
Application number	US-201514589777-A
Country	US
Kind code	A1
Filing date	Jan 5, 2015
Priority date	Jan 5, 2015
Publication date	Jul 7, 2016
Grant date	—

Abstract

Systems and methods for detecting and validating a leak in a fuel cell system are presented. In certain embodiments, various fuel cell stack set points may be adjusted such that adequate H 2 flow data may be obtained to identify and validate an H 2 leak and/or a location of such a leak. In some embodiments, H 2 flow data may be obtained by adjusting certain fuel cell system operating parameters under a variety of operating conditions and/or modes and measuring flow data under such various operational conditions.

First claim

1 . A method for validating a leak in an anode subsystem of a fuel cell system, the method comprising:
determining that a first measured leak flow rate in the anode subsystem exceeds a first reference flow rate threshold; adjusting an anode-to-cathode pressure bias and a current density of the fuel cell system to reference levels; after adjusting the anode-to-cathode pressure bias and current density to the reference levels, measuring a second measured leak flow rate; comparing a plurality of measured leak flow rates obtained at a plurality of anode-to-cathode pressure bias levels with the second measured leak flow rate; and identifying a leak based on the comparison.

2 . The method of claim 1 , wherein comparing the plurality of measured leak flow rates obtained at the plurality of anode-to-cathode pressure bias levels further comprises:
increasing the anode-to-cathode pressure bias; after increasing the anode-to-cathode pressure bias, determining that a third measured leak flow rate exceeds the second measured leak flow rate; decreasing the anode-to-cathode pressure bias; and after decreasing the anode-to-cathode pressure bias, determining that a fourth measured leak flow rate is less than the second measured flow rate and third measured leak flow rate.

3 . The method of claim 1 , wherein the method further comprises:
identifying a leak location in the fuel cell system.

4 . The method of claim 3 , wherein identifying the leak location in the fuel cell system comprises:
increasing a pressure in the cathode subsystem of the fuel cell system; and after increasing the pressure in the cathode subsystem, measuring a fifth measured leak flow rate.

5 . The method of claim 4 , wherein identifying the leak location in the fuel cell system further comprises:
determining that the fifth measured leak flow rate is substantially similar to the second measured leak flow rate; and based on the determination, identifying a leak location in the cathode subsystem.

6 . The method of claim 4 , wherein identifying the leak location in the fuel cell system further comprises:
determining that the fifth measured leak flow rate is greater than the second measured leak flow rate; and based on the determination, identifying a leak location in the anode subsystem.

7 . The method of claim 1 , wherein the method further comprises:
confirming the identified leak, wherein the confirming comprises:
monitoring a pressure decay rate of the anode subsystem during a shutdown operation of the fuel cell system;
determining that the decay rate is faster than a reference threshold decay rate; and
confirming the identified leak based, at least in part, on the determination.

8 . The method of claim 1 , wherein the method further comprises implementing at least one protective action in response to identifying the leak to mitigate damage to the fuel cell system.

9 . The method of claim 8 , wherein the protective action comprises initiating a shutdown operation of the fuel cell system.

10 . The method of claim 8 , wherein the protective action comprises terminating injection of hydrogen in the fuel cell system.

11 . A non-transitory computer-readable storage medium storing instructions that, when executing by a processor, cause the processor to perform a method of validating a leak in an anode subsystem of a fuel cell system, the method comprising:
determining that a first measured leak flow rate in the anode subsystem exceeds a first reference flow rate threshold; adjusting an anode-to-cathode pressure bias and a current density of the fuel cell system to reference levels; after adjusting the anode-to-cathode pressure bias and current density to the reference levels, measuring a second measured leak flow rate; comparing a plurality of measured leak flow rates obtained at a plurality of anode-to-cathode pressure bias levels with the second measured leak flow rate; and identifying a leak based on the comparison.

12 . The non-transitory computer-readable storage medium of claim 11 , wherein comparing the plurality of measured leak flow rates obtained at the plurality of anode-to-cathode pressure bias levels further comprises:
increasing the anode-to-cathode pressure bias; after increasing the anode-to-cathode pressure bias, determining that a third measured leak flow rate exceeds the second measured leak flow rate; decreasing the anode-to-cathode pressure bias; and after decreasing the anode-to-cathode pressure bias, determining that a fourth measured leak flow rate is less than the second measured flow rate and third measured leak flow rate.

13 . The non-transitory computer-readable storage medium of claim 11 , wherein the method further comprises:
identifying a leak location in the fuel cell system.

14 . The non-transitory computer-readable storage medium of claim 13 , wherein identifying the leak location in the fuel cell system comprises:
increasing a pressure in the cathode subsystem of the fuel cell system; and after increasing the pressure in the cathode subsystem, measuring a fifth measured leak flow rate.

15 . The non-transitory computer-readable storage medium of claim 14 , wherein identifying the leak location in the fuel cell system further comprises:
determining that the fifth measured leak flow rate is substantially similar to the second measured leak flow rate; and based on the determination, identifying a leak location in the cathode subsystem.

16 . The non-transitory computer-readable storage medium of claim 14 , wherein identifying the leak location in the fuel cell system further comprises:
determining that the fifth measured leak flow rate is greater than the second measured leak flow rate; and based on the determination, identifying a leak location in the anode subsystem.

17 . The non-transitory computer-readable storage medium of claim 11 , wherein the method further comprises:
confirming the identified leak, wherein the confirming comprises:
monitoring a pressure decay rate of the anode subsystem during a shutdown operation of the fuel cell system;
determining that the decay rate is faster than a reference threshold decay rate; and
confirming the identified leak based, at least in part, on the determination.

18 . The non-transitory computer-readable storage medium of claim 11 , wherein the method further comprises implementing at least one protective action in response to identifying the leak to mitigate damage to the fuel cell system.

19 . The non-transitory computer-readable storage medium of claim 18 , wherein the protective action comprises initiating a shutdown operation of the fuel cell system.

20 . The non-transitory computer-readable storage medium of claim 18 , wherein the protective action comprises terminating injection of hydrogen in the fuel cell system.

Assignees

• Gm Global Tech Operations Inc

Inventors

• Pace Stephen D
• Cai Jun
• Sinha Manish

Classifications

• H01M8/04432

  Pressure differences, e.g. between anode and cathode · CPC title

• H01M8/04104 Primary

  Regulation of differential pressures · CPC title

• H01M8/04783

  Pressure differences, e.g. between anode and cathode · CPC title

• H01M8/04679

  of fuel cell stacks · CPC title

• H01M8/04952

  of fuel cell stacks · CPC title