Based on the basic sliding pressure curve, through the interrelationship of the thermal system and the internal influence of the coordinated control of the unit, an optimization function for the full-stroke opening flow characteristics and overlap degreeof the high-pressure regulating valve is established, and the economic relationship function for fitting the throttling loss of the high-pressure regulating valve with the power consumption of the feed water pump is obtained. Based on the coupling relationshipbetween the sliding pressure characteristic curve of the high-pressure valve under typical working conditions and the exhaust parameters of the high-pressure cylinder, the desuperheating water of the boiler reheater and other data.