Fuel cell system and fuel cell vehicle

A method for controlling a fuel cell system, the fuel cell system comprising

• a fuel cell,
• a hydrogen tank configured to store hydrogen,
• a filler port with which a hydrogen filling device configured to fill hydrogen into the hydrogen tank is engaged,
• a filling flow path connecting the filler port and the hydrogen tank,
• a supply flow path connecting the fuel cell and the hydrogen tank,
• a first pressure sensor disposed in the filling flow path and configured to detect pressure in the filling flow path,
• a first valve disposed in the filling flow path between the filler port and the first pressure sensor and configured to allow a hydrogen flow in a direction only from the filler port toward the hydrogen tank,
• a second valve disposed in the filling flow path between the first pressure sensor and the hydrogen tank and configured to allow the hydrogen flow in the direction only from the filler port toward the hydrogen tank when the hydrogen is filled into the hydrogen tank,
• a second pressure sensor disposed in the supply flow path and configured to detect pressure in the supply flow path,
• a sealing valve configured to seal a part of the supply flow path where the second pressure sensor is disposed in a non-generating state of the fuel cell, and
• a transmitter configured to transmit a signal indicating pressure in the hydrogen tank to the hydrogen filling device, and
• the method comprising:
• upon determination that filling hydrogen into the hydrogen tank is about to start,
• instructing the transmitter to transmit a first signal indicating that the pressure in the hydrogen tank is a first sensor value, when the first sensor value detected by the first pressure sensor is equal to or higher than a reference pressure predetermined to be higher than atmospheric pressure;
• and
• instructing the transmitter to transmit a second signal indicating that the pressure in the hydrogen tank is a second sensor value detected by the second pressure sensor, when the first sensor value is lower than the reference pressure.