Anode leak location detection

Patent metadata

Field	Value
Publication number	US-9564648-B2
Application number	US-201213706781-A
Country	US
Kind code	B2
Filing date	Dec 6, 2012
Priority date	Dec 6, 2012
Publication date	Feb 7, 2017
Grant date	Feb 7, 2017

Abstract

A system and method for quantifying an anode leak location in a fuel cell system. The system and method include determining there is a leak in an anode sub-system of a fuel cell stack and estimating a first effective leak area using a first leak flow value and first operating parameters. The system and method also include increasing airflow to a cathode side of the fuel cell stack and estimating a second leak effective area using a second leak flow value and second operating parameters. The system and method further include comparing the first leak effective area to the second leak effective area and determining an anode outflow leak location based on the comparison between the first and second leak effective areas.

First claim

What is claimed is:

1. A method for determining whether one of at least three possible locations in an anode sub-system of a fuel cell system is leaking, said method comprising:
determining there is a leak in the anode sub-system of the fuel cell system;
determining a first leak flow value defining a leak rate of the leak during first system operating parameters;
estimating a first effective leak area using the first leak flow value and the first system operating parameters for each of the three possible leak locations;
determining a second leak flow value defining a leak rate of the leak during second system operating parameters, said second system operating parameters including an increased cathode airflow to a fuel cell stack that is greater than a cathode airflow to the fuel cell stack during the first system operating parameters;
estimating a second effective leak area using the second leak flow value and the second system operating parameters for each of the three possible leak locations;
comparing the first effective leak area to the second effective leak area for each of the three possible leak locations; and
determining which of the three possible locations the leak may be occurring based on the difference between the first effective leak area and the second effective leak area for each location.

2. The method according to claim 1 wherein the three possible leak locations are anode inlet to cathode outlet, anode outlet to cathode inlet and anode to ambient environment.

3. The method according to claim 1 further comprising increasing a hydrogen input concentration to the fuel cell stack, determining a third leak flow value defining a leak rate of the leak during the increased hydrogen input concentration, comparing the third leak flow value to the first leak flow value, and determining that the leak is occurring at an anode outlet or an anode inlet based on a difference between the first leak flow value and the third leak flow value.

4. The method according to claim 1 further comprising taking remedial actions for mitigating the leak.

5. A method for determining whether one of three possible locations in an anode sub-system of a fuel cell system is leaking, said possible leak locations including anode inlet to cathode outlet, anode outlet to cathode inlet and anode to ambient environment, said method comprising:
determining there is a leak in the anode sub-system of the fuel cell system;
determining a first leak flow value defining a leak rate of the leak during first system operating parameters;
estimating a first effective leak area using the first leak flow value and the first system operating parameters for each of the three possible leak locations;
determining a second leak flow value defining a leak rate of the leak during second system operating parameters, said second system operating parameters including an increased cathode airflow to a fuel cell stack that is greater than a cathode airflow to the fuel cell stack during the first system operating parameters;
estimating a second effective leak area using the second leak flow value and the second system operating parameters for each of the three possible leak locations;
comparing the first effective leak area to the second effective leak area for each of the three possible leak locations;
determining which of the three possible locations the leak may be occurring based on the difference between the first effective leak area and the second effective leak area for each location;
increasing a hydrogen input concentration to the fuel cell stack;
determining a third leak flow value defining a leak rate of the leak during the increased hydrogen input concentration;
comparing the third leak flow value to the first leak flow value; and
determining that the leak is occurring at an anode outlet or an anode inlet based on a difference between the first leak flow value and the third leak flow value.

6. The method according to claim 5 further comprising taking remedial actions for mitigating the leak.

7. A control system for determining whether one of at least three possible locations in an anode sub-system of a fuel cell system is leaking, said control system comprising:
a controller programmed with:
means for determining there is a leak in the anode sub-system of the fuel cell system;
means for determining a first leak flow value defining a leak rate of the leak during first system operating parameters;
means for estimating a first effective leak area using the first leak flow value and the first system operating parameters for each of the three possible leak locations;
means for determining a second leak flow value defining a leak rate of the leak during second system operating parameters, said second system operating parameters including an increased cathode airflow to a fuel cell stack that is greater than a cathode airflow to the fuel cell stack during the first system operating parameters;
means for estimating a second effective leak area using the second leak flow value and the second system operating parameters for each of the three possible leak locations;
means for comparing the first effective leak area to the second effective leak area for each of the three possible leak locations; and
means for determining which of the three possible locations the leak may be occurring based on a difference between the first effective leak area and the second effective leak area for each location.

8. The method according to claim 1 wherein the first and second effective leak areas are estimated using:

A
i
eff

=

Mw
AnOut

·

n
.

Leak

P
AnIn

·

(

2
·

L
⁢
2

⁢

⁢

m
3

R
⁡

(

T
CoolIn

+

C
⁢
2
⁢
K

)

Assignees

• Gm Global Tech Operations Llc

Inventors

• Di Fiore Daniel C
• Sinha Manish
• Falta Steven R
• Lang Matthew A

Classifications

• H01M8/04664 Primary

  Failure or abnormal function · CPC title

• H01M8/04679 Primary

  of fuel cell stacks · CPC title

• H01M8/04753

  of fuel cell reactants · CPC title

• H01M8/04097

  with recycling of the reactants (H01M8/04119, H01M8/04104 take precedence) · CPC title

• H01M8/0441

  of cathode exhausts · CPC title