Patent ID: 8765313

Claim:
A fuel cell system comprising: a reformer that generates reformed gas using reforming fuel; a fuel cell that generates electric power using the reformed gas generated by the reformer; and a control device programmed to include a plurality of different stop control modes for stopping operation of the fuel cell system, and further programmed to select a specific stop control mode among the plurality of stop control modes, according to a cause of a malfunction of the fuel cell system, wherein the plurality of stop control modes includes at least three stop control modes, wherein each stop control mode in the plurality of stop control modes is associated with a different degree of urgency of stopping the fuel cell system, wherein the control device is further programmed to select among the at least three stop control modes depending on severity or type of the cause of the malfunction of the fuel cell system, and wherein the at least three stop control modes comprise: a stop control mode of prohibiting supply of the reformed gas generated by the reformer to the fuel cell by interrupting communication between the reformer and an anode of the fuel cell, a stop control mode of prohibiting the supply of the reformed gas generated by the reformer to the fuel cell by interrupting the communication between the reformer and the anode of the fuel cell, and prohibiting supply of the reforming fuel to the reformer, and a stop control mode of prohibiting the supply of the reformed gas generated by the reformer to the fuel cell by interrupting the communication between the reformer and the anode of the fuel cell, prohibiting the supply of the reforming fuel to the reformer, and prohibiting supply of combustion air to the reformer.