In a control device for a power converter converting electric power of a fuel cell stack, the power converter includes first and second reactors, a first switching element connected to the first reactor, and a second switching element connected to the second reactor. The second reactor is located closer to a cooling water discharge manifold than the first reactor. The control device configured to: set first and second duty cycles of the first and second switching element; and execute limit control in which, by controlling the setting of the first and second duty cycles, a second amount of heat generated by the second reactor due to a second current is limited to a value smaller than a first amount of heat generated by the first reactor due to a first current within a period of at least multiple ON-OFF cycles of the first and second switching elements.

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.

The power supply device is configured on an aircraft and includes a secondary battery, a transformer, a fuel cell and a bypass switch. The transformer is electrically connected between the secondary battery and the aircraft. The fuel cell is suitable for providing a first output current to the aircraft. The bypass switch is connected in parallel with the transformer. The transformer has a first output voltage set value. When a first output terminal voltage of the fuel cell is lower than the first output voltage set value and the bypass switch is in a non-conducting state, a second output current of the secondary battery is provided to the aircraft via the transformer. When the first output terminal voltage is lower than the first output voltage set value and the bypass switch is in a conducting state, the second output current is provided to the aircraft via the bypass switch.

A fuel cell vehicle includes a hydrogen injector, a controller, and a first power supply. The hydrogen injector is configured to open when supplied with a current large than or equal to a predetermined current threshold. The controller is configured to control a current that is supplied to the hydrogen injector such that the supply current follows a target current value. The first power supply is configured to supply electric power to the hydrogen injector and a prescribed auxiliary. The controller is configured to increase the target current value when the controller detects at least one of a first start signal for starting the prescribed auxiliary and a second start signal for informing startup of the prescribed auxiliary.

A method and a system for controlling startup of a fuel cell are provided. The method includes sensing a startup request signal and boosting a Bi-directional high-voltage DC/DC Converter (BHDC) of a main bus stage when the startup request signal has been sensed by a controller. A valve of an air/hydrogen line is then opened together with the boosting of the BHDC and the startup of the fuel cell is completed by allowing an output of the fuel cell after the valve of the air/hydrogen line is opened.

The invention relates to a method for operating a fuel cell arrangement which has a fuel cell for providing electrical energy in a circuit, at least one fuel cell auxiliary unit, the circuit electrically connected to the fuel cell via a DC-DC converter, and a battery. In this case, it is provided that, in order to place the fuel cell into operation, the battery be electrically connected to the circuit and the fuel cell auxiliary unit be operated with electrical energy drawn from the battery, wherein the battery is electrically disconnected from the circuit, and the DC-DC converter is operated in non-clocked mode in at least one operating mode of the fuel cell arrangement after placement into operation. The invention further relates to a fuel cell arrangement.

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.

A fuel cell system installed in a vehicle includes: a fuel cell; a secondary battery; a load including a drive motor and an air compressor; a fuel cell converter; a secondary battery converter; a failure detection unit; a first state determination unit; a reverse rotation detection unit; and a control unit. The control unit performs a limp-home traveling control that supplies electric power from the secondary battery to the drive motor when the secondary battery converter fails. When the vehicle is not in the first state, the control unit prohibits regeneration of the drive motor. When the vehicle is in the first state, the control unit supplies a reaction current to the air compressor. When the reaction current is applied and a reverse rotation of the air compressor is detected, the control unit does not apply the reaction current thereafter.

In a control device for a power converter converting electric power of a fuel cell stack, the power converter includes first and second reactors, a first switching element connected to the first reactor, and a second switching element connected to the second reactor. The second reactor is located closer to a cooling water discharge manifold than the first reactor. The control device configured to: set first and second duty cycles of the first and second switching element; and execute limit control in which, by controlling the setting of the first and second duty cycles, a second amount of heat generated by the second reactor due to a second current is limited to a value smaller than a first amount of heat generated by the first reactor due to a first current within a period of at least multiple ON-OFF cycles of the first and second switching elements.

A fuel cell power and control system may comprise a fuel cell stack configured to generate electric power, a fuel carrier for the fuel cell stack, at least one temperature control element in thermal communication with the fuel carrier, and an electronic control unit (ECU) configured to regulate electric current supplied to the temperature control element to control a rate at which a fuel is released from the fuel carrier. In various embodiments, the system further comprises an energy storage device configured to receive the electric power from the fuel cell stack. In various embodiments, the ECU is configured to vary the electric current supplied to the temperature control element in response to the voltage across the energy storage device varying.