Patent ID: 7947403

Claim:
A fuel cell system, comprising: a fuel cell that generates electric power via an electrochemical reaction between a fuel gas and an oxidizing gas; an oxidizing gas supply section for supplying the oxidizing gas to the fuel cell; a secondary battery that performs charging and discharging of electric power; an electric power distribution section that supplies electric power generated by the fuel cell to an accessory device required for power generation by the fuel cell and to the secondary battery for its charging, or supplies electric power discharged by the secondary battery to at least one of the accessory device and a load; and a control section that performs warm-up control processing for warming up the secondary battery by alternately performing first processing and second processing, the first processing for controlling the electric power distribution section to supply generated power of the fuel cell to the accessory device and the secondary battery, and the second processing for controlling the electric power distribution section to supply at least discharged power from the secondary battery to at least one of the accessory device and the load; wherein the control section includes a power generation calculation unit that calculates, when performing the warm-up control processing, a chargeable/dischargeable power level of the secondary battery from a detected value of charge rate of the secondary battery; and calculates a power generation level of the fuel cell based on the calculated chargeable/dischargeable power level; and a drive control unit for the oxidizing gas supply section, that controls a drive state of the oxidizing gas supply section based on the calculated value of power generation level of the fuel cell indicated in an output command from the power generation calculation unit; and the power generation calculation unit gradually changes a magnitude of the power generation level of the fuel cell at a time of transition between the first processing and the second processing, the power generation level being indicated in the output command input into the drive control unit for the oxidizing gas supply section.