Study on the Influence of Rotor Eccentricity on the Characteristics of Hybrid Stator Pole Bearingless Switched Reluctance Motor

Because the rotor of bearingless switched reluctance motor (BSRM) can only be supported by suspension force, and it cannot be supported by conventional mechanical bearings. Therefore, when the suspension force or load of the BSRM is disturbed, the rotation axis of rotor always rotates near the geometric center of the stator, it’s hard to make sure that it’s in the geometric center of the stator. That is to say, for bearingless motor, the rotor eccentricity is inevitable, in other words, electromagnetic characteristics of the motor must be affected by the eccentric operation of the rotor. In this paper, the influence of the rotor radial eccentricity, including three cases, on the electromagnetic characteristics is analyzed. At the same time, the influence of the rotor axial eccentricity on the electromagnetic characteristics is also analyzed. Finally, the finite element (FEM) analysis results are discussed, the relationship between rotor eccentricity and electromagnetic characteristics is also analyzed.