| 摘要 |
PURPOSE:To make stable operation for a plant continuable by computing a fact that steam is in an overheating area on the basis of temperature and pressure a in an outlet of a high pressure steam turbine, controlling a turbine bypass valve at the required time, and avoiding any wet operation. CONSTITUTION:Air 1 is fed to a waste heat boiler 5 as exhaust gas after being fed to a gas turbine 3 by way of an air regulating blade 2. On the other hand, steam passes through a main hot air pipe 7 from a heater 6 and is fed to a high pressure steam turbine 9 by way of a governing valve 8. And, this steam is fed to a waste heat boiler 5 from a condenser 16 via a feed water pipe 17 after being fed to a low pressure turbine 15 by way of a reheater 12 or the like. In this case, the temperature and pressure detected by each of detectors 25 and 26 installed in an outlet of the high pressure steam turbine 9 are compared with each other by a computing element 27, whereby a fact that the steam is in an overheating area is detected. And, when it is so judged that the steam cannot keep the overheating area longer, the governing valve 8 is closed by a controller 28, and a turbine bypass valve 22 is opened instead, thus wet operation is avoided. |
