STEAM TURBINE SYSTEM

摘要

PROBLEM TO BE SOLVED: To provide a steam turbine system capable of achieving both improvement in power generation efficiency at a time of operation at rated power generation output and prompt regulation of a power generation output based on change in power demand.SOLUTION: A steam turbine system includes: a boiler 1; a steam regulating valve 4 provided on a main steam pipe 2 communicating the boiler 1 with a steam turbine; an overload valve 6 provided in an overload steam pipe 5 branched off from the steam pipe 2 to bypass the steam regulating valve 4 and connected to a low pressure side of the steam turbine with respect to the main steam pipe 2; and a slit 31 through which steam discharged from the overload steam pipe 5 passes when the steam flows into steam turbine stages, a width C of the slit 31 in an axial direction of a turbine rotor 15 being set smaller than an inside diameter d of the overload steam pipe 5 (d>C).