Application of analog flexible fuzzy control to coordinated control system to improve load response speed of generating unit to AGC

Abstract

Coordinated control system is a strong coupling, multiple-input and multiple-output system. Load and the main steam pressure control are interdependence, mutual constraints; it is non-linear dynamic characteristics of unit; boiler side emerge large delay. Therefore it is very difficulty of obtaining a satisfactory control effect for conventional control strategy. In order to improve the coordination control system performance, the non-linear mathematical models of once-through boiler unit are given. Analysis of the conventional boiler feed-forward control system and based on the thought that dynamic energy and static energy separation, the boiler analog flexible fuzzy control feed-forward controller is structured and applied in coordination control system of generator unit. This paper cites the concept of analogy flexible fuzzy control and applies the concept to coordinate control system. Through system parameters are reasonably set, dynamic energy and static energy can maintain a balance. The application of analogy flexible fuzzy control can overcome the big lag and the big inertia of boiler. It can effectively improve rate of coordinate control system responding to AGC load instructions.