Steam cooled system in combined cycle power plant

摘要

To earlier find occurrence of disorder in a high temperature portion of a combustor, blade or the like in a steam cooled type gas turbine, which is constructed such that a cooling steam is supplied into the high temperature portion and the cooling steam after being used for cooling is recovered, so that the gas turbine my be operated safely, the invention provides an outlet steam monitoring system. In this system there are provided a temperature detector (48) for detecting an outlet temperature of said steam after being used for cooling and a control device (50) which, when being supplied with a detected signal of said temperature detector (48) for comparison with a predetermined temperature value, is adapted to puts out a warning signal as well as a signal for throttling opening of a fuel flow control valve (55) to a predetermined opening or a signal for closing a shut-off valve (56), if a detected temperature of said temperature detector (48) exceeds said predetermined temperature value.