| 摘要 |
PROBLEM TO BE SOLVED: To provide a fuel cell system capable of warming up a fuel cell quickly, and an operation method therefor.SOLUTION: The fuel cell system comprises: a fuel cell stack 10; a hydrogen tank 21; a compressor 31; an oxidant gas supply passage; an oxidant off-gas discharge passage; a diluter 40 for diluting an anode off-gas with a cathode off-gas; a branched gas passage for a branch gas heading toward the diluter 40 to pass through; a back pressure valve 32 for adjusting the pressure of the branch gas; OCV determination means for determining whether or not the OCV of the fuel cell is equal to or higher than a prescribed OCV at system startup time; and IV characteristic reduction means for reducing the IV characteristic of a single cell 11 by letting power generation started by the fuel cell stack 10 and also reducing the stoichiometric ratio of oxygen after the OCV determination means determined that the OCV of the single cell 11 is equal to or higher than a prescribed OCV. The back pressure valve 32 reduces the pressure of the branch gas to be introduced into the diluter 40 when the IV characteristic of the single cell 11 is reduced by the IV characteristic reduction means. |
