Combined cycle power plant

摘要

A combined cycle power plant comprises a gas turbine system (41) and a steam cycle system (42) having a steam turbine (118) to be driven by the steam generated by the waste heat of the exhaust gas of the gas turbine system (41), wherein the steam from the steam cycle system (42) flows through a gas turbine cooling system (43) of the gas turbine system to cool the gas turbine blades and other elements of the gas turbine system to be cooled and the waste heat of the gas turbine system is effectively collected. The gas turbine cooling system (43) has cooling ducts (150, 160) formed in two or more than two elements (114, 149) of the gas turbine system to be cooled such as the gas turbine blades (149) and the combustor (114) of the gas turbine system so that steam is made to flow through the cooling ducts (150, 160) of these two or more than two elements (114, 149) to be cooled to effectively and maximally exploit the cooling potential and the waste heat collecting potential of the steam and hence improve the overall thermal efficiency of the plant. The plant can selectively supply steam and/or water from the steam cycle system or high pressure air from the gas turbine system.