METHOD FOR INCREASING POWER OF COMBINED-CYCLE POWER PLANT, AND COMBINED-CYCLE POWER PLANT FOR CONDUCTING SAID METHOD

摘要

PROBLEM TO BE SOLVED: To provide a method for temporary increasing the power of a gas turbine (11), which is part of a combined-cycle power plant (10).;SOLUTION: Exhaust gas of the gas turbine (11) is used in a heat recovery steam generator (13) to generate steam for a water/steam cycle including a steam turbine (12) with a high pressure steam turbine (20), an intermediate pressure steam turbine (21) and a low pressure steam turbine (22). The method comprises the step of injecting steam from the water/steam cycle at a predetermined injection pressure into the gas turbine (11). The efficiency is improved by taking steam of a lower pressure than the predetermined injection pressure out of the water/steam cycle, increasing the pressure of the steam taken out of the water/steam cycle to the predetermined injection pressure by subjecting it to a compression step in separate compressing means (14), and injecting the compressed steam into the gas turbine (11). Preferably, the separate compressing means (14) comprises at least one steam-driven ejector.;COPYRIGHT: (C)2016,JPO&INPIT