Patent ID: 7968240

Claim:
A fuel cell system comprising: a fuel cell stack including a plurality of fuel cells; a positive high voltage stack bus in electrical communication with a positive terminal of the fuel cell stack, and a negative high voltage stack bus in electrical communication with a negative terminal of the fuel cell stack; an inverter in electrical communication with the fuel cell stack via the positive high voltage stack bus and the negative high voltage stack bus, the inverter configured to selectively regulate a power of the fuel cell stack and short circuit the fuel cell stack, wherein the inverter has a first transistor and a second transistor in an inverter phase leg, the inverter configured to convert a direct current (DC) from the fuel cell stack to an alternating current (AC) when regulating the power of the fuel cell stack; a voltage sensor in electrical communication with the fuel cell stack, the voltage sensor configured to measure a voltage of the fuel cell stack; and a controller in electrical communication with the inverter and the voltage sensor, the controller configured to selectively cause the inverter to short circuit the fuel cell stack when the voltage of the fuel cell stack as measured by the voltage sensor is below a predetermined voltage limit, the short circuit caused when the first transistor and the second transistor of the inverter are simultaneously enabled to allow a shoot-through fault and short circuit the fuel cell stack.