COOLING STEAM CONTROL METHOD FOR COMBINED CYCLE POWER GENERATION PLANTS

摘要

A gas turbine steam-cooling system, provided with an exhaust gas heat recovering boiler (2) which operates a gas turbine (1C) to generate steam by utilizing the exhaust heat from the gas turbine (1C), for controlling a combined cycle plant by installing a steam line from the exhaust gas heat recovering boiler (2) to steam turbines (3, 4) to drive the steam turbines (3, 4), branching the steam line from the exhaust gas heat recovering boiler (2) to cool high-temperature parts (8) of the gas turbine (1C), and returning cooled steam to the steam line, characterized in that the flow rate of the cooling steam to the high-temperature members (8) is controlled according to dynamic characteristics of the exhaust gas heat recovering boiler (2) while the load on the gas turbine (1C) is changing.