Patent ID: 6643348
Filing Date: 2003-11-04
Classification: G21D,Y02E

Abstract:
A steam turbine control device in a nuclear power plant comprising:a main steam system connected to lead steam generated in a nuclear reactor into a steam turbine comprising a main steam line, a main steam isolation valve, and a main steam control valve; a turbine by-pass system connected to by-pass the steam turbine, branched from the main steam system, and connected to a condenser, the turbine by-pass system comprising a turbine by-pass valve; a main steam pressure detector in the main steam system; a main steam pressure control calculating means, for outputting a main steam pressure control signal dependant on the signal from the main steam pressure detector; a reactor dome pressure detector in the nuclear reactor; a reactor dome pressure control calculating means for outputting a reactor dome pressure control signal dependent on the signal from the reactor dome pressure detector; a main steam isolation valve fully closed position detector for outputting a pressure control change trigger signal when the main steam isolation valve is detected to be fully closed; and a pressure control signal calculating means for outputting a pressure control signal to control the position of the main steam control valve and/or the turbine by-pass valve comprising a pressure control signal changeover means to change over a pressure control signal from the reactor dome pressure control signal to the main steam pressure control signal when the main steam isolation valve is detected to be closed by the main steam isolation valve fully closed position detector.