Abstract:Due to the serious environmental pollution caused by SO2 in the flue gas of thermal power plants and the low degree of automation and control precision of the current desulfurization control link of power plants,in order to optimize the desulfurization control link of power plants,the establishment of accurate system model is an important prerequisite for the control of SO2 emissions.In this paper,based on the identification results of a wet flue gas desulfurization system in a power plant,a feedforward and feedback compound control system model corresponding to the slurry pH value and outlet SO2 concentration is established,and a PID controller parameter tuning method based on Multiple Capacity Process(MCP) standard transfer function model is presented.The simulation results verify the applicability and accuracy of the MCP-PID tuning method.This method provides the mathematical model basis for the desulfurization control link optimization of power plant and provides a new idea for the control strategy selection of multivariable continuous system.