COMBINED CYCLE POWER PLANT AND START-UP METHOD OF THE SAME

摘要

There is provided a combined cycle power plant in which a high-pressure steam turbine and an intermediate-pressure steam turbine can operate in a state where amounts of thermal effect thereof are close to a limit value, and capable of reducing start-up time. A combined cycle power plant includes: an exhaust heat recovery boiler 20 that includes a high-pressure superheater 21a which superheats steam for a high-pressure steam turbine 31, and a reheater 22 which reheats steam for an intermediate-pressure steam turbine 32; bypass pipes 26, 27 through which steam bypasses the high-pressure superheater 21a and the reheater 22; bypass valves 104, 105 that regulate flow rates of steam which flows through the bypass pipes 26, 27; and a bypass controller 206 that controls the bypass valves 104, 105 such that a difference between thermal effect-amount margins of the turbines 31, 32 is decreased.