Method for operating a combined cycle power plant

Abstract

A method for operating a combined cycle power plant is disclosed, which has a gas turbine installation and a water-steam cycle connected to the gas turbine installation by a waste heat steam generator and has at least one steam turbine, the gas turbine installation includes a compressor, a combustion chamber, and a turbine. To cool the turbine, air compressed at the compressor is removed, cooled in at least one cooler flowed through by water, thus generating steam, and introduced into the turbine. At least with the gas turbine installation running, prior to or during the start-up of the water-steam cycle, waste heat, which is contained in the steam generated in the at least one cooler, is used to good effect for pre-heating the installation inside the combined cycle power plant.

1 - 15 . (canceled) 
     
     
         16 . A combined cycle power plant comprising:
 a gas turbine installation including a compressor, a combustion chamber, and a turbine;   a waste heat steam generator; and   a water-steam cycle connected to the gas turbine installation by the waste heat steam generator, the water-steam cycle including at least one steam turbine;   at least one cooler configured and arranged to be flowed-through by water, the at least one cooler being in fluid communication with the compressor and the turbine, the at least one cooler being configured and arranged to receive air compressed at the compressor, cool said air in the at least one cooler when water is flowed therethrough thus generating steam, and introduce cooled air into the turbine; and   at least one additional steam line operatively connecting the water-steam cycle with the at least one cooler.   
     
     
         17 . A combined cycle power plant according to  claim 16 , further comprising:
 a first steam line fluidly communicating the at least one cooler with the waste heat steam generator.   
     
     
         18 . A combined cycle power plant according to  claim 17 , further comprising at least one valve, and wherein:
 the waste heat steam generator includes a steam drum, or a moisture separator and a super heater; and   the first steam line is in fluid communication with the steam drum, the super heater, or both via said at least one valve.   
     
     
         19 . A combined cycle power plant according to  claim 16 , further comprising:
 a valve; and   a second steam line fluidly communicating the at least one cooler with the steam turbine via said valve, for evacuating and/or for providing sealing steam.   
     
     
         20 . A combined cycle power plant according to  claim 16 , wherein the water-steam cycle comprises means for condensing steam emerging from the steam turbine, which means for condensing are operated under vacuum, and further comprising:
 a valve;   an evacuation apparatus connected to the means for condensing; and   a steam line fluidly communicating the at least one cooler via said valve to the evacuation apparatus.   
     
     
         21 . A combined cycle power plant according to  claim 20 , further comprising:
 a further steam line including at least one control valve in fluid communication with the steam turbine.   
     
     
         22 . A combined cycle power plant according to  claim 16 , further comprising:
 a feedwater boiler, wherein the at least one cooler is fluidly connected to the feedwater boiler for supplying water; and   a steam line including a valve from the at least one cooler to the feedwater boiler.