Active Stabilization of a Repulsive Magnetic Bearing Using the Motion Control of Permanent Magnets

Abstract

This paper investigated the control system design of a repulsive magnetic bearing using the motion control of permanent magnets. In the repulsive magnetic bearing system, the radial motions of the rotor were passively supported by repulsive forces between ring-shape permanent magnets ; the axial motion was actively controlled by the motion control of the permanent magnets with a pair of voice coil motors. Two control schemes, PD control and state-variable feedback, were applied for the stabilization of the axial motion. The results showed that the dynamic performance of the controlled system could be adjusted more flexibly by state-variable feedback.