FUEL CELL SYSTEM

To provide a fuel cell system in which, if a downstream side valve to control the discharge of oxidant gas from a fuel cell is fixed/closed, the fixing/closing of the downstream side valve can be released while maintaining durability of a drive part of the downstream side valve.SOLUTION: In an embodiment of the present disclosure, a controller 201 in a fuel cell system 101 opens an inlet sealing valve 174 and a bypass valve 191 in system startup and closes the bypass valve 191 in a state where the rotational speed of a compressor 172 is controlled to a freeze releasing compressor rotational speed Comprpm1, thereby performing freeze releasing control to release fixing/closing of an outlet integrated valve 181 due to freezing.SELECTED DRAWING: Figure 1 【課題】燃料電池からの酸化剤ガスの排出を制御する下流側弁が閉固着した場合に、下流側弁の駆動部の耐久性を維持しつつ、下流側弁の閉固着を解除できる燃料電池システムを提供する。【解決手段】本開示の一態様は、燃料電池システム１０１において、コントローラ２０１は、システム起動時に、入口封止弁１７４及びバイパス弁１９１を開弁させ、コンプレッサ１７２の回転数を凍結解除コンプレッサ回転数Ｃｏｍｐｒｐｍ１に制御した状態で、バイパス弁１９１を閉弁させることにより、出口統合弁１８１の凍結による閉固着を解除する凍結解除制御を行う。【選択図】図１