Research On Fuzzy Neural System And Its Application In Main Steam Temperature Control System Of Power Plant

In modern thermal power plant,it is very strict that the control of main steam temperature,but because of the big delay of the main steam temperature object's characteristic,big inertial,nonlinear and the variety model with variety time,which causing as to it's control more difficult. It is very difficult to obtain good effect of control by conventional PID control.It is necessary to set up the mathematics models of controlled plants if applying control means of modern control theory such as self-adaptive control,optimal control.And these control systems have large calculation and bad character of real time in general.These disadvantages make them be not able to meet the need of real production process and limit the application of them in modern power station.Now the generator units are developing towards large capacity and high parameters. The characters of production units of power station become more and more complex but the demand to quality of control becomes more and more strict.The new control means are in bad need to control them effectively.Neural network has the ability of learning and expressing any nonlinear relation.It can approximate any continuous function and their any order derivatives with any precision if it has the correct layers of networks and the correct number of hidden units.So all kinds of advanced control means based on neural network is an effective way that resolve the control problem of modern power station.Fuzzy control is good at expressing knowledge and its logical reasoning is similar to man's thought.But this system depends on the man's subjective factor too much and lack the capacity of adaptation and learning.This dissertation is dedicated to solve the practical control problems in power station under the existence of thermal control system characterized by large delay and time varying.The dissertation adopt fuzzy neural network control that is a kind of compound intelligence control based on the nerve network theories and the fuzzy logical, the study ability of the neural network is used to optimize logical experience rule and adjust proportional gene, which can be realize to the valid control of the main steam temperature.And make use of the matlab proceeding simulative experiment, fuzzy neural network controller arrives the better simulative curve under the different load, we can find out fuzzy neural network control system has the very good robustness and very good control quality.