Fuel cell system and method for controlling same

A fuel cell system, comprising:

• a fuel gas supply line that supplies fuel gas from a fuel gas supply source to the fuel cell;
• pressure-regulating means provided on the fuel gas supply line and configured to regulate a pressure of the fuel gas supplied from the fuel gas supply source;
• a circulation route configured to return the fuel gas discharged from the fuel cell to the fuel gas supply line;
• a fuel gas pump configured to circulate the fuel gas in the circulation route;
• and
• a control unit configured to control the system, wherein
• the circulation route is connected to the fuel gas supply line such that the fuel gas is returned to the fuel gas supply line upstream of the pressure-regulating means,
• the control unit is configured to output a control signal to the fuel gas pump to control the fuel gas that is circulated in the circulation route, and
• the pressure-regulating means is configured such that a pressure of the fuel gas downstream of the pressure-regulating means eases pressure fluctuation of the fuel gas upstream of the pressure-regulating means.