FUEL CONTROL METHOD FOR GAS TURBINE, CONTROL DEVICE FOR EXECUTING SAID METHOD, AND GAS TURBINE INSTALLATION PROVIDED WITH SAID CONTROL DEVICE

A control device (100) includes a fuel equivalent value calculation unit (150) for determining the flow rate of fuel supplied to a gas turbine in accordance with a target value deviation (”Nt) between an actual rotation speed (Nr) and a target rotation speed (Nt), an upper limit deviation calculation unit (131) for obtaining an upper limit deviation (”Pu) which is a deviation between a set upper limit output (Pu) and an actual output (Pr), a lower limit deviation calculation unit (132) for obtaining a lower limit deviation (”Pd) which is a deviation between a set lower limit output (Pd) and the actual output (Pr), and a parameter-changing unit (140) for changing any one parameter among the target rotation speed, the actual rotation speed, and the target value deviation so that the target value deviation decreases when the actual rotation speed decreases and the upper limit deviation is small, and so that the target value deviation increases when the actual rotation speed increases and the lower limit deviation is small.