Patent ID: 8497042

Claim:
A fuel cell system comprising: a reformer; a fuel cell body to which a fuel gas reformed through the reformer and air are supplied and in which the supplied fuel gas and air are separated from each other and caused to flow and contact on respective electrodes to perform electric power generation; a moisture quantity adjustment device configured to adjustably separate a portion of moisture included in the fuel gas supplied from the reformer; a pressure regulating valve actuator disposed in a gas channel extending from the moisture quantity adjustment device to the fuel cell body that regulates a pressure of the fuel gas supplied from the moisture quantity adjustment device; a first feedback channel disposed between the moisture quantity adjustment device and the reformer; a second feedback channel disposed between the fuel cell body and the reformer; a feedback control unit comprising: a moisture quantity calculating section configured to: calculate a moisture quantity of the fuel gas supplied to the reformer; calculate a historical separated quantity of moisture from the moisture quantity adjustment device; and calculate a target moisture quantity of a fresh fuel for reformation; and a feedback moisture quantity adjusting section configured to determine an amount of moisture to provide to the reformer in order for the moisture included in the fuel gas to be supplied to the fuel cell body in an appropriate quantity, wherein the feedback control unit is configured to: drive an open or close position of the pressure regulating valve actuator so that the moisture in the fuel gas supplied to the fuel cell body is the appropriate quantity, send the moisture to be fed back to the reformer via the first feedback channel, and provide the moisture generated in the fuel cell body to be fed to the reformer via the second feedback channel; a first distributing valve actuator that distributes the moisture circulated through the second feedback channel to the reformer and to external the fuel cell system, wherein the feedback control unit is configured to drive an open or close position of the first distributing valve actuator so that the moisture in the fuel gas supplied to the fuel cell body is the appropriate quantity; a water storage tank that reserves the moisture separated at the moisture quantity adjustment device; and a third feedback channel that feeds moisture reserved in the water storage tank to the reformer.