Patent ID: 9732676
Date: 2017-08-15
CPC Classifications: F02C,F05D

Claim:
1. A valve control device provided in a gas turbine, the gas turbine comprising: a combustor for generating combustion gas by combusting fuel; a turbine driven by the combustion gas generated by the combustor; a flow rate regulating valve for regulating a flow rate of the fuel to be supplied to the combustor; and a pressure regulating valve disposed upstream of the flow rate regulating valve in a fuel passage for supplying the fuel to the combustor, for regulating a fuel pressure, wherein the valve control device controls at least an opening degree of the pressure regulating valve, the valve control device comprising: a detection section for detecting a load decrease of the gas turbine; and a pressure control section for throttling the opening degree of the pressure regulating valve to an unclosed opening degree on the basis of an output demand value of the gas turbine after the load decreases when the detection section detects the load decrease, wherein the pressure control section obtains a fuel demand value indicating an amount of the fuel to be supplied to the combustor on the basis of the output demand value for the gas turbine after the load decrease, and determines the opening degree of the pressure regulating valve on the basis of the fuel demand value, an air flow rate calculation section for calculating a flow rate of air to be fed to a compressor on the basis of the output demand value, the compressor introducing compressed air into the combustor, wherein the pressure control section derives the fuel demand value corresponding to the air flow rate calculated by the air flow rate calculation section, atmospheric temperature, and the output demand value, by using heat balance data indicating at least one of state values at inlets and outlets of components constituting the gas turbine.