METHOD AND DEVICE FOR CONTROLLING MAIN STEAM TEMPERATURE OF BOILER

摘要

PURPOSE: To improve the following property of control by a method wherein integrating process is stopped when the load of a boiler is changed with a changing rate higher than the set value of main steam temperature of the boiler. ;CONSTITUTION: A main steam temperature is controlled so as to be an objective value by a method wherein the amount of spray water poured into superheated steam is controlled based on a control amount obtained by effecting proportional integrating process of a difference ΔT₁ between the set value T₁* of the main steam temperature of a boiler and a main steam temperature feedback value T₁, detected by a main steam temperature sensor, by a proportional integration control means 105. When the load of the boiler is changed with a changing rate higher than the set value T₁* of main steam temperature, the integrating process effected by the proportional integration control means 105 is stopped. As a result, the returning operation of integration after finishing the change of the load is eliminated and, therefore, the response of a superheater spray valve 110 with respect to the fluctuation of the main steam temperature after finishing the change of the load is quickened. According to this method, the following property of control can be improved.;COPYRIGHT: (C)1993,JPO&Japio