Fuel gas supply device

A fuel gas supply device for supplying a fuel gas to a plurality of fuel nozzles provided in a combustor of a gas turbine, the fuel gas supply device comprising:

• a fuel gas supply system for supplying the fuel gas to each of the plurality of fuel nozzles via a fuel gas supply line connected to a fuel gas supply source;
• a plurality of flow rate regulation valves provided in the fuel gas supply line and for regulating a flow rate of the fuel gas to each of the plurality of fuel nozzles;
• a shutoff valve provided on an upstream side of the plurality of flow rate regulation valves in the fuel gas supply line;
• a bypass line provided to bypass the shutoff valve with respect to the fuel gas supply line;
• a shutoff valve bypass valve provided in the bypass line;
• and
• a control device for controlling an upstream pressure of the plurality of flow rate regulation valves in the fuel gas supply line, wherein
• the control device
• controls the upstream pressure using a supply pressure of the fuel gas supply source by opening the shutoff valve and closing the shutoff valve bypass valve in a case where the gas turbine is in a normal operation state, and
• controls the upstream pressure to be lower compared to the normal operation by closing the shutoff valve and opening the shutoff valve bypass valve in a non-normal operation state including at least one of the time of ignition or increase in speed of the gas turbine.