초록 ▼

A method of controlling fuel of a gas turbine provided with a two-stage combustion type combustor wherein the fuel of gas is fed to the combustor only through a primary fuel nozzle under a low-run of the gas turbine and through the both the primary fuel nozzle and a secondary fuel nozzle under a hig

A method of controlling fuel of a gas turbine provided with a two-stage combustion type combustor wherein the fuel of gas is fed to the combustor only through a primary fuel nozzle under a low-run of the gas turbine and through the both the primary fuel nozzle and a secondary fuel nozzle under a high-run of the gas turbine, and controlled by a fuel control valve according to a load signal, comprises measuring the flow rate of the fuel passing through the fuel control valve; controlling the fuel control valve according to the measured flow rate so that the flow rate will be constant or a scheduled value when the gas turbine reaches to a predetermined load; and switching fuel supply to the combustor from the primary fuel nozzle to through both the primary and secondary fuel nozzles while the fuel control valve is controlled according to the measured flow rate signal.

대표청구항 ▼

A method of controlling fuel gas fed to a gas turbine provided with a two stage combustion type combustor having a primary fuel nozzle for supplying a fuel gas to a primary combustion zone of said combustor, a secondary fuel nozzle for supplying a fuel gas into a secondary combustion zone of said co

A method of controlling fuel gas fed to a gas turbine provided with a two stage combustion type combustor having a primary fuel nozzle for supplying a fuel gas to a primary combustion zone of said combustor, a secondary fuel nozzle for supplying a fuel gas into a secondary combustion zone of said combustor, and a fuel control valve provided on a fuel line from which primary and secondary fuel lines branch off downstream of said fuel control valve, said primary fuel line leading to said primary fuel nozzles and said second fuel line to said secondary fuel nozzles, the method comprising the steps of: supplying a fuel gas into said combustor only through said primary fuel nozzle through said fuel control valve while controlling said fuel control valve in accordance with a load control signal so as to operate said gas turbine under a load schedule during a low load operation; measuring a flow rate of the fuel gas to the combustor through said fuel control valve to generate a signal related to the measured flow rate value; generating switching instruction signals when said turbine reaches a predetermined load; controlling the flow rate of the fuel gas to said combustor by taking, as a reference flow rate, a measured flow rate at a time when the predetermined load is reached, comparing successively measured fuel flow rates in the measuring step with the reference flow rate and actuating said fuel control valve so that a difference between the reference flow rate and the successively measured fuel flow rates is a scheduled value; switching fuel supply to said combustor from only through said primary fuel nozzle to both said primary and secondary fuel nozzles by controlling a switching valve provided on said secondary fuel line so that a ratio between a flow rate of fuel gas in said primary fuel line and a flow rate of fuel gas in said secondary fuel line will be a predetermined value while controlling said fuel control valve based on said measured flow rate; and controlling the flow rate of the fuel gas to said combustor according to the low control signal after a termination of the fuel supply switching so as to operate said turbine on the load schedule.