Fuzzy-Tuning PID Controller for Nonlinear Electromagnetic Levitation System

In the paper we derive a dynamic model of the magnetic levitation system and propose a Fuzzy-Tuning PID (FTP) controller that selects the parameters of the PID controller by using fuzzy inference system. Conventional PID controller can be applied to control the electromagnet levitation. However, it is uncertain in case of load and airgap change. To solve the problem, we designed fuzzy rules of FTP considering the control response of system. We estimate the optimal parameters of PID controller through four performance indices and show the performance of PID control system in case of load and airgap response change. The performance of PID controller is compared with the proposed FTP controller. The performance of proposed system was not only faster rising time, settle time and reduced overshoot but also greater flexibility than conventional PID controller.