Method and apparatus for starting a combined cycle power plant

摘要

A combined cycle power plant (10) utilizing an air injection apparatus (60) for lowering the temperature and raising the mass of the exhaust gas provided to the heat recovery steam generator (22) from the gas turbine portion (12) of the plant. The air injection apparatus is utilized during startup of the plant to permit the gas turbine portion to be operated at a power level sufficiently high to ensure compliance with emissions regulations while at the same time not exceeding an upper exhaust temperature limit for warming the steam generator. The augmented exhaust stream (76) allows the steam generator to more quickly generate enough steam to roll the steam turbine (30), thereby shortening the overall startup sequence.