Eccentricity Analysis and Efficiency Estimation of 12/14 Hybrid Stator Pole Bearingless SRM

The radial force to suspend the rotor in a constant air-gap for bearingless switched reluctance motor (BLSRM) is dependent on air-gap and force current. Due to the non-linear characteristic of inductance, the radial force is much affected by the rotor eccentricity. In order to keep constant air-gap of rotor, the nonlinear characteristics of eccentricity should be analyzed. Further, the auxiliary bearing is always used to restrict the maximum eccentricity of the rotor in industry. In this paper, the rotor eccentricity effect in the proposed 12/14 BLSRM is analyzed. Meanwhile, the efficiency of the 8/10 and proposed BLSRMs is estimated. The analysis results further verify the validity of the proposed BLSRM.