300MW Unit Control Object Modeling And Control Algorithm

With the capacity of electrical grid and generators increasing, the nation power grid request the power plant running more safely and response quickly. Power generating unit is a inertia, long delay and uncertainty controlled process, especially in the boiler. Conventional PID controller is difficult to obtain satisfactory control effect in dealing with long delay process. Establish the boiler accurate mathematical model, predict the boiler parameters trend, overcome boiler delay and large inertia effectively and promote CCS system control quality are important research topics in the thermal control field.This article uses the field test data to establish the mathematical model of coordinated control system through test method, which provides a model for the follow-up control algorithm research. The same method is used in main steam temperature system, air volume - oxygen control system, primary air pressure control system. After making of the unit dynamic characteristic and the decoupling method of the coordinated control system, use one-way decoupling method to decoupe. Considering the characters such as inertia, long delay of the coordinated control system, the conventional PID unable to obtain good control effect, generalized predictive control method is proposed in this paper. Make analysis of the principle of the algorithm and then perform a matlab experiment using the conventional PID and generalized predictive control method respectively on the coordination control system model which is obtained in section two. At last, compare the two control algorithm. Through the simulation results, the generalized predictive control algorithm control effect is better than conventional PID algorithm, which has current tracking abilities, small overshoot and strong anti-interference ability.