SPEED GOVERNING CONTROLLER FOR STEAM TURBINE, METHOD FOR CONTROLLING THE SAME AND STEAM TURBINE

摘要

PROBLEM TO BE SOLVED: To provide a speed governing controller for a steam turbine which can satisfy both of suppression of valve body vibration of an intercept valve and turbine output control of high response.SOLUTION: A speed governing controller for a steam turbine includes: a control valve opening calculation part that calculates an opening of a control valve 6 according to a system frequency f of a system grid 21 and a CV reduction ratio; an intercept valve opening degree calculation part that calculates an opening degree of an intercept valve 7 according to the system frequency f and the ICV reduction ratio; a timer 46 that measures a passing time after the opening of the intercept valve 7 is reduced; and a control part that controls the intercept valve 7 depending on a calculated opening when the passing time is less than a setting time, and controls the intercept valve 7 into a fully opened state when the passing time reaches the setting time.