A hybrid method for parameter tuning of PID controllers

A method is proposed to optimal-tune the parameters of PID controllers. Different from traditional techniques, the tuning procedure of the proposed method is described in terms of fuzzy rules, in which the input variables are the error signal and its derivative, and the output variables are the PID parameters. A genetic algorithm (GA) is then used to search for the optimal PID parameters that will minimize the integral of the squared error. In the simulation examples, comparison between the proposed method and other tuning techniques is made. In addition, simulation is also carried out on a ball and beam system to show the application of the proposed method to nonlinear systems.