초록 ▼

A gas turbine steam cooled system has a high temperature portion 8 outlet steam temperature maintained to a predetermined value without a cooling steam pressure becoming lower than the pressure in the gas turbine cylinder. Steam coming from an intermediate pressure superheater 10 of a waste heat rec

A gas turbine steam cooled system has a high temperature portion 8 outlet steam temperature maintained to a predetermined value without a cooling steam pressure becoming lower than the pressure in the gas turbine cylinder. Steam coming from an intermediate pressure superheater 10 of a waste heat recovery boiler 2 is led into the high temperature portion 8 of the gas turbine for cooling thereof. The temperature of the cooling steam at the outlet of the high temperature portion 8 is detected by a high temperature portion outlet steam temperature detector 15, and a signal thereof is sent a lower value selector 19 via a temperature controller 11. Pressure in the gas turbine cylinder is detected by a gas turbine cylinder pressure detector 17, and pressure of the cooling steam at the high temperature portion 8 outlet is detected by a high temperature portion outlet steam pressure detector 16. A differential signal thereof is sent to a pressure controller 18. Signals from the temperature controller 11 and the pressure controller 18 are inputted into the lower selector 19, and temperature control valve 12 is controlled by the lower value thereof to be opened and closed.

대표청구항 ▼

[ What is claimed is:] [1.]1. An operating method of a steam cooled system in a combined cycle power plant comprising a combination of a gas turbine plant and a steam turbine plant, said combined cycle power plant including:a gas turbine, said gas turbine including a turbine cylinder and a high temp

[ What is claimed is:] [1.]1. An operating method of a steam cooled system in a combined cycle power plant comprising a combination of a gas turbine plant and a steam turbine plant, said combined cycle power plant including:a gas turbine, said gas turbine including a turbine cylinder and a high temperature portion;a steam turbine;a waste heat recovery boiler for generating steam turbine driving steam using waste heat of said gas turbine;a steam cooled system using steam for cooling said high temperature portion of said gas turbine; anda steam recovery system for recovering superheated steam coming from said steam cooled system into said steam turbine;wherein said operating method comprises:providing a high temperature control valve at a cooling steam outlet of said high temperature portion; andcontrolling said high temperature control valve so as to perform cooling steam temperature control so that the temperature of cooling steam coming out of said high temperature portion is set to a predetermined value and to perform cooling steam pressure control, which is preferential to cooling steam temperature control, so that pressure of the cooling steam coming out of said high temperature portion may not become lower than pressure in said turbine cylinder of said gas turbine.