Fractional stabilizing controller for a magnetic levitation system

Abstract

Due to high instability and non-linearity the control of magnetic levitation systems has received considerable interest, furthermore they can eliminate friction. They have wide application in in high precision positioning platforms, high speed trains, Magnetic bearings, vibration isolation systems and wind tunnel levitation systems. Fractional order (FO) controllers are among the nascent solutions for increasing closed-loop performance, robustness and stability assurance. Hence they can be used in Magnetic levitation systems. For the comparison purpose a simple integer order PID controller is designed. The tuning of the controller (FO PID and PID) parameters are done using Particle swarm optimization and Genetic algorithm. The integer order system model is identified to Fractional order using FOMCON toolbox by using an initial guess Fractional Mag-Lev model. Among the frequency domain identification methods Hartley, Levy& Vinagre method is used in this brief.