Self-optimizing Fuzzy PID Control Of Superheated Steam Temperature

The boiler superheater recovers the steam from the boiler's flue gas energy and turns it into superheated steam to improve the boiler's thermal efficiency while keeping the steam turbine from water hammer.Since superheater pipes in large thermal power plants usually operate at critical temperatures,monitoring the temperature of superheated steam is an important step in ensuring the safe production of thermal power plants.The superheated steam temperature must be guaranteed to be within reasonal range during operation.The temperature of the superheated steam can't be too high or too low,or it will cause damage to the tube to burst and affect efficiency.In order to ensure the safe and economic operation of thermal power plants,good control quality is needed,the system should adapt to changes in unit load and external disturbance.While analysing the superheater working process and the dynamic and static characteristics of superheated steam temperature,the requirements of superheated steam temperature control system are clarified,and the series PID control scheme is taken as the basic control scheme of the paper to quickly eliminate the internal disturbance,and get control precision and strong adaptability.Based on the PID controller,the fuzzy PID controller is designed.The model structure of the fuzzy PID controller is given.The paper analyzed the functions of scaling factor and quantization factor in the fuzzy control algorithm.Aiming at the problem that the parameter value uniquely determined by the empirical formula can not adapt to the complex working conditions,an algorithm idea of ??optimizing the quantization factor and the scale factor by an intelligent optimization algorithm is proposed.The simulated annealing algorithm is used to improve particle swarm optimization algorithm to overcome the shortage of it.Numerical simulation experiments verify the optimization convergence and search ability of the optimized algorithm.The optimized algorithm is applied to search the best of fuzzy PID controller parameters,namely the quantization factor and the scale factor setting.By constructing the simulation,the results shows that the fuzzy PID controller through optimization has better setpoint following performance than the fuzzy PID controller and series controller,and also has good anti-interference and load adaptability.