The effect of non-uniform magnetization of permanent magnets on the performance of a repulsive type magnetic bearing system

A permanent magnet bearing (MB) system utilizing the repulsive forces operating between the stator and rotor permanent magnet for levitation and radial control has been fabricated in our laboratory. The consistency of the permanent magnet magnetization effects the continuous steady-state and dynamic performance of the system. Since both the magnets are repelling each other, there will be demagnetization of the magnetization of the permanent magnet. Due to demagnetization or ageing or manufacturing asymmetry, the field distribution may not be uniform along the periphery of the magnet. In this paper the effect of this magnetization non-uniformity on the performances of the bearing system has been studied.