FUEL CELL SYSTEM AND METHOD FOR CONTROLLING FUEL CELL SYSTEM

A fuel cell system according to the present embodiment includes a fuel cell stack, a cooling-water tank having a cooling-water supply port to which a cooling-water supply pipe coupled to a cooling-water inlet manifold is coupled at the other end, a first oxygen-containing-gas discharge pipe coupled at one end to an air outlet manifold being coupled to the cooling-water tank at the other end, the cooling-water tank being configured to supply cooling water from the cooling-water inlet manifold, and a pressure-loss part to which a second oxygen-containing-gas discharge pipe coupled at one end to an air discharge port of the cooling-water tank is coupled at the other end, and to which a fuel-gas discharge pipe coupled at one end to a fuel-outlet manifold provided in a downstream outlet of the fuel-electrode passage is coupled at the other end.