First Order Integral Sliding Mode Control Of The Magnetically Levitated 4-Pole Type Hybrid Electromagnet

Abstract

In this study, 4-pole type yoke hybrid electromagnet is modeled with respect to motion dynamics of the system. The hybrid electromagnet inherently has a nonlinear characteristic and from the point view of controllability, it is unstable. This paper concerns the design of robust controller using first order integral sliding mode control method. Thus, the system becomes stable and robust against parametric uncertainties, nonlinearity, unmodeled uncertainties and external disturbance. Magnetic levitation system includes sensors that only measure the air gap. In order to estimate other states of the system, the full order disturbance observer is designed and integrated into the control loop. The estimated disturbance value is factored by the appropriate conversion gain and added to the input signal of the plant. The efficiency of control algorithm will be given in the paper by computer simulations.