| 摘要 |
PURPOSE:To start a combined cycle power plant safely by opening a steam governer valve with predetermined speed and maintaining at constant opening thereafter controlling with some opening characteristic. CONSTITUTION:At first a gas turbine 1 is started while maintaining a steam governer valve 15 at the minimum to rotate a directly coupled steam turbine 2. Upon reaching to rated rotation, said valve 15 is fully closed. Upon reaching to such timing where high temperature high pressure steam is produced in a waste heat recovery boiler 4 to open said valve 15, an open command signal is provided to a start controller 13 and if the water level in a drum 14 indicated by a level meter 20 is lower than setting level, said valve 15 is opened with constant speed while upon reaching to setting level the opening is maintained constant immediately and when dropping below the setting level, it is opened again with constant speed to full open while repeating said operation thus to complete start control. Consequently tripping fault caused by the water level in the drum can be prevented to realize safe starting operation. |
