Patent ID: 8800296

Claim:
A gas turbine control method for a gas turbine that includes a combustor and a plurality of nozzle groups grouped into a first main nozzle group and a second main nozzle group so as to be arranged on the circumference of a pilot nozzle, each of the first main nozzle group and the second main nozzle group having different numbers of main nozzles and supplying fuel gas to the combustor, and that switches the first main nozzle group and the second main nozzle group used for fuel supply according to an operating condition, the method comprising the steps of: receiving the operating condition from the gas turbine and calculating at least a first adjustment parameter, a second adjustment parameter and a third adjustment parameter from the operating condition; registering in advance at least the first adjustment parameter selected from a fuel-supply sharing ratio of the first main nozzle group with respect to a fuel supply command value, at least the second adjustment parameter selected from a fuel-supply sharing ratio of the second main nozzle group with respect to the fuel supply command value, and at least the third adjustment parameter selected so as to adjust at least one of the fuel-supply sharing ratio of the first main nozzle group and the fuel-supply sharing ratio of the second main nozzle group in a main nozzle group switching period, during which the first main nozzle group that has been used is switched to the second main nozzle group that is going to be used; determining a fuel supply command value of the first main nozzle group and a fuel supply command value of the second main nozzle group during the main nozzle group switching period using the fuel-supply sharing ratio of the first main nozzle group, the fuel-supply sharing ratio of the second main nozzle group, and the first, second and third adjustment parameters; updating the first, second and third adjustment parameters registered in advance, according to the operating condition of the gas turbine in which a fuel control based on the determined fuel supply command value of the first main nozzle group and the fuel supply command value of the second main nozzle group are reflected; and registering the updated adjustment parameters as adjustment parameters to be used next.