Alternate Tooth Wound PM Motor design for Inductance based Position Estimation

Alternate tooth wound fractional slot concentrated winding (FSCW) offer high inductance, magnetic and physical isolation required for fault-tolerant PMSM design. However they have low saliency ratio compared to their distributed winding counterparts. As a result, saliency based sensor-less rotor position estimation techniques show poor performance. In this paper, an alternate tooth wound FSCW PMSM design with improved saliency and rotor position sensing is presented. In the design process, similarities between alternate tooth wound FSCW PMSM and SRM are considered. The presented design utilizes inset rotor configuration and achieves an inductance variation similar to SRM. Finite element analysis results corresponding to 3-phase 12 slots 10 poles PMSM is presented. An algorithm for achieving inductance tracking based position sensing is proposed. High frequency injection technique is used for inductance tracking and obtaining position information. This is demonstrated through co-simulation of 3-phase finite element motor model and power electronic converter at rated current excitation.