MULTISHAFT TYPE COMBINED CYCLE PLANT AND METHOD FOR CONTROLLING THE SAME

摘要

PROBLEM TO BE SOLVED: To provide a multishaft type combined cycle plant provided with a system materializing stability of plant operation and lifetime extension.

SOLUTION: When a load on a gas turbine generator of one shaft of the multishaft type combined cycle plant suddenly drops, superheated steam generated by remaining heat of an exhaust gas boiler 2b in a side of load drop is released to a steam turbine side. A command to close an isolation valve 5b- of the exhaust gas boiler is issued and a turbine bypass valve 22b- is simultaneously closed when pressure difference between before and after the isolation valve 5b- of the exhaust gas boiler gets to proximity of zero.

COPYRIGHT: (C)2004,JPO