Provided is a two-power-supply load driving fuel cell system capable of improving the durability of the fuel cell and the power efficiency of the system. Even if the variation of a load terminal voltage occurs, the variation of the output terminal of an FC can be suppressed due to the high-speed operation of an FCVCU including an SiC-FET, enabling the durability of the FC to be ensured. In addition, since IGBTs are employed in a BATVCU having large average passing power, the power loss of a fuel cell system can be reduced. It is therefore possible to construct a system that takes advantage of the characteristics of the switching elements used in the FCVCU and the BATVCU.

A current control system includes a boost converter, and a converter controller that selectively performs control in a continuous mode using a calculated duty ratio for the continuous mode and control in a discontinuous mode using a calculated duty ratio for the discontinuous mode. The converter controller performs, at least in calculation of the duty ratio for the continuous mode, rising speed adjustment processing for adjusting a parameter used for the calculation of the duty ratio so that a rising amount of the duty ratio is restricted relative to the duty ratio used in a last cycle in accordance with a predetermined limit value, so as to restrict a rising speed of the duty ratio for the continuous mode more than a rising speed of the duty ratio for the discontinuous mode.

A DC voltage distribution arrangement and method of controlling a DC voltage distribution system, the DC voltage distribution system including a DC voltage bus, a fuel cell electrically connected to the DC voltage bus, an energy storage and an energy storage converter, wherein the input of the energy storage converter is connected to the energy storage and the output of the energy storage converter is connected to the DC bus. The method comprises providing a DC voltage reference for the energy storage converter, the energy storage converter controlling the voltage of the DC voltage bus by providing power from the energy storage or to the energy storage, detecting power flow of the energy storage converter, and changing the DC voltage reference on the basis of the detected power flow to change the power taken from the fuel cell.

An FC control unit selectively supplies electrical power of an FC unit to one or both of a battery and a battery heater, based on at least one of whether an SOC of the battery is higher or lower than a preset threshold value, and whether a battery temperature is higher or lower than a preset temperature threshold.

A power supply device disposed on an aircraft to provide a power to the aircraft is provided. The aircraft has an average required power value. The power supply device includes a secondary battery, a transformer and a fuel cell. The transformer is coupled between the secondary battery and the aircraft. The fuel cell is coupled to the aircraft and is adapted to provide a first output current to the aircraft. The transformer has an output voltage set value. When the first output end voltage of the fuel cell is lower than the output voltage set value, the transformer provides a second output current of the secondary battery to the aircraft. The output voltage set value is in a voltage range with a fuel cell output power between the maximum power value of characteristic curve of the fuel cell and the average required power value of the aircraft.

A fuel cell system configured to generate an electric power by supplying an anode gas and a cathode gas to a fuel cell includes: a connection line configured to connect the fuel cell to an electric load; a converter connected to the connection line and a battery, the converter being configured to adjust a voltage of the connection line; a target output current calculating unit configured to calculate a target output current of the fuel cell in accordance with a load of the electric load; a converter control unit configured to carry out a switching control for the converter in accordance with the target output current; and a flow rate control unit configured to control a flow rate of the cathode gas to be supplied to the fuel cell in accordance with the target output current. The target output current calculating unit sets up an upper limit to the target output current on the basis of a generated electric power of the fuel cell and a guaranteed minimum voltage of the connection line for ensuring performance of the fuel cell and the electric load.

A fuel cell vehicle includes a cell stack, a DC level converter, an output unit, a first switching unit disposed between a positive output terminal of the DC level converter and a positive input terminal of the output unit, a second switching unit disposed between a negative output terminal of the DC level converter and a negative input terminal of the output unit, a resistor and a third switching unit connected to each other in series between the positive output terminal of the DC level converter and the negative output terminal of the DC level converter, a fourth switching unit disposed between a contact point between the resistor and the third switching unit and the positive input terminal of the output unit, and a controller for controlling switching operation of the first, second, third and fourth switching units according to an operation mode.

An electronic circuit arrangement for a fuel cell arrangement may include a first electrical voltage converter stage and a second electrical voltage converter stage. An electrical fuel cell voltage may be appliable to the first electrical voltage converter stage on an input side. The electrical fuel cell voltage may be convertible into a first electrical output voltage of the first electrical voltage converter stage via the first electrical voltage converter stage. The first electrical output voltage may be appliable to the second electrical voltage converter stage on an input side. The first electrical output voltage may be convertible into a second electrical output voltage of the second electrical voltage converter stage via the second electrical voltage converter stage. An electrical interconnection of the first electrical voltage converter stage and the second electrical voltage converter stage may be switchable between a first interconnection state and a second interconnection state.

A fuel cell activation apparatus including: a storage battery; a first current sensor detecting a current outputted by the storage battery; a first switch switching between supplying the current outputted by the storage battery and supplying a current provided from the system power supply; a second switch switching between transmitting a result of detecting by the first current sensor and transmitting a result of detecting by a second current sensor which detects the current provided from the system power supply; and a control unit switching between a normal mode for activating, based on the result of detection performed by the second current sensor, the fuel cell using the current provided from the system power supply and a self-sustained mode for activating, based on the result of detection performed by the first current sensor, the fuel cell using the current outputted by the storage battery.

There is provided a fuel cell system. When receiving an instruction to start power generation of the fuel cell system, the fuel cell system is configured: (i) to obtain an output limit value of a secondary battery according to a predetermined relationship of a temperature of the secondary battery to the output limit value of the secondary battery by using the temperature of the secondary battery; (ii) to control a battery converter such as to increase a voltage of a smoothing capacitor for boosting included in the battery converter to a start-time target voltage that is higher than an open circuit voltage of a fuel cell, such that an output power of the secondary battery does not exceed the output limit value; and (iii) to operate the compressor such as to start supplying the cathode gas by the cathode gas supply system and to open the main stop valve such as to start supplying the anode gas by the anode gas supply system.