Abstract: A fuel cell system includes a fuel cell stack, a fuel gas supply channel, a fuel gas circulation channel, a circulating pump that is driven by a pump motor having no rotation detecting sensor, and an ECU. When a method for operating the fuel cell system determines that the circulating pump is frozen in a low-temperature environment, the method performs a first step of performing a brake mode to limit the rotation of the pump motor while passing current to the pump motor, to thereby heat the pump motor. The method further performs a second step of, after rotating the pump motor, determining that the circulating pump has unfrozen if the rotational speed of the pump motor exceeds a given value.

Abstract: A fuel cell system includes a fuel cell stack, a plurality of injectors capable of adjusting a flow rate of anode gas supplied to the fuel cell stack, and an ECU causing the plurality of injectors to operate. The plurality of injectors include a main injector, and a BP injector that operates when power that exceeds a prescribed power generation amount is generated. The ECU performs an operational check of causing the BP injector to operate at least once and judging whether the BP injector is normal or abnormal, during a period from when the fuel cell system is activated to when the fuel cell system stops.

Abstract: A fuel cell system includes a fuel cell stack, a fuel gas supply channel, a fuel gas circulation channel, a circulating pump that is driven by a pump motor having no rotation detecting sensor, and an ECU. When a method for operating the fuel cell system determines that the circulating pump is frozen in a low-temperature environment, the method performs a first step of performing a brake mode to limit the rotation of the pump motor while passing current to the pump motor, to thereby heat the pump motor. The method further performs a second step of, after rotating the pump motor, determining that the circulating pump has unfrozen if the rotational speed of the pump motor exceeds a given value.

Abstract: A fuel cell system includes a fuel cell, an accumulator configured to store a fuel gas, a gas remaining quantity acquisition unit configured to obtain a remaining quantity of the fuel gas stored in the accumulator, and a power generation control unit. When the remaining quantity of the fuel gas stored in the accumulator is decreased to a threshold value, the power generation control unit performs switching from humid power generation control to dry power generation control.

Abstract: A fuel cell system includes a fuel cell stack, a plurality of injectors capable of adjusting a flow rate of anode gas supplied to the fuel cell stack, and an ECU causing the plurality of injectors to operate. The plurality of injectors include a main injector, and a BP injector that operates when power that exceeds a prescribed power generation amount is generated. The ECU performs an operational check of causing the BP injector to operate at least once and judging whether the BP injector is normal or abnormal, during a period from when the fuel cell system is activated to when the fuel cell system stops.

Abstract: A fuel cell system includes a fuel cell, an accumulator configured to store a fuel gas, a gas remaining quantity acquisition unit configured to obtain a remaining quantity of the fuel gas stored in the accumulator, and a power generation control unit. When the remaining quantity of the fuel gas stored in the accumulator is decreased to a threshold value, the power generation control unit performs switching from humid power generation control to dry power generation control.