Robust PI-PD Controller Design for Magnetic Levitation System


This paper presents a design of robust PI-PD position controller for Magnetic Levitation Ball system. The Magnetic Levitation system considered in this work is taken as a ferromagnetic ball suspended in a voltage controlled magnetic field. The Magnetic Levitation system is unstable, because electromagnetic force is very sensitive and there is a noise that creates acceleration forces on the steel ball resulting the instability due to existence of positive poles causing the steel ball to move into the unbalanced region. The robust controller is aimed to keep a steel ball suspended in the air in the desired position by maintaining the balance between the magnetic force and ball's weight. The Particle Swarm Optimization (PSO) method is used to tune the gains of the PI-PD controller. The simulation and experimental results show the effectiveness of the designed controller.