Fuel cell system, and method of testing a fuel cell for a gas leak

A fuel cell power system comprising:

• a fuel cell defining a fluid vessel having a fuel inlet and bleed outlet;
• a fuel valve upstream of the fuel inlet;
• a bleed valve downstream of the fuel outlet;
• and
• a pressure transducer in fluid communication with the fluid vessel, wherein a pressure test of the fluid vessel is selectively performed in-situ.

A method of testing a hydrogen fuel cell system in-situ for a hydrogen leak, the hydrogen fuel cell system including a main fuel valve, a main bleed outlet, auxiliary fuel valves in fluid communication with the main valve and downstream from the main valve, auxiliary bleed valves in fluid communication with the main bleed outlet and upstream from the main bleed outlet, a plurality of hydrogen fuel cell modules having respective fuel inlets coupled to the auxiliary fuel valves and having respective outlets coupled to the auxiliary bleed valves, the method comprising:

• providing a pressure transducer;
• providing a hydrogen sensor in gas sensing relation to the fuel cell system;
• and
• in response to the hydrogen sensor sensing a hydrogen gas concentration above a predetermined threshold, identifying which module is leaking by controlling the auxiliary fuel and auxiliary bleed valves to pressure test one module at a time by supplying fuel to the tested module, while the auxiliary bleed valve for the tested module is closed, until the pressure of the tested module reaches a predetermined level, then discontinuing the supply of fuel to the tested module and monitoring if pressure of the tested module drops by more than a predetermined amount during a predetermined amount of time.

A hydrogen fuel cell system comprising:

• a main fuel valve;
• a main bleed outlet;
• a plurality of auxiliary fuel valves in fluid communication with the main valve and downstream from the main valve;
• a plurality of auxiliary bleed valves in fluid communication with the main bleed outlet and upstream from the main bleed outlet;
• a plurality of hydrogen fuel cell modules having respective fuel inlets coupled to the auxiliary fuel valves, having respective outlets coupled to the auxiliary bleed valves, and having respective polymer electrolyte membranes between the fuel inlets and fuel outlets;
• at least one pressure transducer downstream of the main fuel valve and upstream of the main bleed outlet;
• a hydrogen sensor in gas sensing relation to the fuel cell modules;
• and
• a controller coupled in controlling relation to the main and auxiliary fuel and bleed valves and configured to, in response to the hydrogen sensor sensing a hydrogen gas concentration above a predetermined threshold, identify which module is leaking by controlling the auxiliary fuel and auxiliary bleed valves to pressure test one module at a time by supplying fuel to the tested module, while the auxiliary bleed valve for the tested module is closed, until the pressure of the tested module reaches a predetermined level, then discontinuing the supply of fuel to the tested module and monitoring if pressure of the tested module drops by more than a predetermined amount during a predetermined amount of time.

A fuel cell system comprising:

• a main fuel valve;
• a main bleed outlet;
• a plurality of auxiliary fuel valves in fluid communication with the main valve and downstream from the main valve;
• a plurality of auxiliary bleed valves in fluid communication with the main bleed outlet and upstream from the main bleed outlet;
• a plurality of fuel cell sub-systems having respective fuel inlets coupled to the auxiliary fuel valves, having respective outlets coupled to the auxiliary bleed valves, and having respective polymer electrolyte membranes between the fuel inlets and fuel outlets;
• a pressure transducer in pressure sensing relation to each fuel cell sub-system;
• and
• a controller coupled in controlling relation to the main and auxiliary fuel and bleed valves and configured to control the auxiliary fuel and auxiliary bleed valves to pressure test certain of the sub-systems one at a time by supplying fuel to the tested sub-system, while the auxiliary bleed valve for the tested sub-system is closed, until the pressure of the tested sub-system reaches a predetermined level, then discontinuing the supply of fuel to the tested sub-system and monitoring if pressure of the tested sub-system drops by more than a predetermined amount during a predetermined amount of time using the pressure transducer that is in pressure sensing relation to the sub-system being tested.