A Novel Mathematic Model of Bearingless Switched Reluctance Motors

Radial weight and rotary torque load often demand large winding current in a bearingless switched reluctance motor (BSRM). This will tend to cause magnetic saturation. But traditional mathematic model can not fit for this saturated working state, which has formatted a sever limitation. With a BSRM model in Maxwell, its magnetic saturation characteristics were analyzed, and a critical criterion was computed. Then a novel mathematic model was established with Maxwell tensor method and confirmed by Finite element computing results. It could fit for both unsaturated and saturated working state, and also satisfy reversibility condition. These were both very useful for nonlinear decoupling with state feedback method and wide application in industry process. This proposed modeling and analyzing method could also provide useful references for motor's optimization design and control algorithm research.