Optimal Winding Arrangements of a Bearingless Switched Reluctance Motor

Winding arrangements of a bearingless switched reluctance motor strongly influence the operation state of its power converters so much as the rotation and levitation of the motor. This paper proposes some optimal winding arrangements, which suit for a three-phase half-bridge converter or a three-phase four-leg converter. First, the optimal main winding arrangement is proposed. Then, this paper analyzes the influence factors of the midpoint voltage of a three-phase half-bridge converter applied to the radial force winding under the invariable radial load. Consequently, four kinds of optimal winding arrangements are given, which can balance the midpoint voltage. Moreover, according to influences of the winding arrangement on the operation state of a three-phase four-leg converter applied to the radial force winding, the paper proposes other four kinds of optimal winding arrangements, which fit the three-phase four-leg converter. The experimental results are also included to verify the theoretic analysis.