Sliding Mode Control for Active Magnetic Bearings

The paper evaluates the sliding mode control methodology as a control law for an active magneticbearing. Developments in power electronics has made it possible to implement a modern control theory to various kinds of electrical and mechanical systems. This paper describes sliding mode control of a single-axis magnetic bearing’s actuator. Sliding mode control (SMC) offers several advantages over the other control methods as follows: robustness; good dynamic response; simple implementation. Sliding mode control is a non-linear, model-based control method supported by the Lyapunov stability theory. It has been proved to be an efficient technique to provide good tracking performance, applied to non-linear systems with external disturbances. It also allows the plant model to be imprecise, for example a model that has been simplified due to difficulties in representing system dynamics. Among applications where sliding mode control has been applied successfully there are: submarines, ground vehiclesand aeroplanes.