Genetic Algorithm In Pid Control

PID (Proportion, Integral, Differential) control is one of the most wildly used rules in control field because of its simple structure, high reliability and high robustness. To the performance of the controller the tuning of PID parameters is important, but still complex and difficult. The principals and common methods of PID controller parameters tuning were specified in this paper.Genetic algorithm is a new optimizing searching method based on biology evolutionary theory. It has taken many researchers' attention since brought foreword in the sixties of 20 century. With much research on it, GA has been used in- many fields including function optimization, control systems, machine learning, communication, signal processing, etc. In recent years, GA was applied to the tuning of PID controller's parameters by some researchers.Some improvements like protecting the best individual, accepting immigrations as well as employing adaptive crossover and mutation operators are presented to overcome the slow and premature convergence shortages of Standard Genetic Algorithms. By applying this modified genetic algorithm to the optimizing of parameters of several kinds of system's PID controller, Better performances of control system are achieved and simulation result based on MATLAB shows its feasibility and utility; by applying this modified genetic algorithm to AC servo motor, comparison result shows that the modified algorithm has good convergence.In the end, a conclusion is made based on summarizing all the work done by the author. Also, We have some problems need to settle in the future is indicated.