Abstract:
Fractional slot concentrated winding (FSCW) features modular stator and single-tooth winding, while the interior permanent magnet (IPM) rotor exhibits less permanent magnet flux and fault current. To realize the fault-tolerant capability of the machine, this paper combines FSCW with IPM and adopts a multiple 3-phase winding structure. Meanwhile, the possible slot-pole combinations of FSCW-IPM are studied, and detailed analyses on the magnetomotive force (MMF) harmonics, torque performance, saliency ratio, inductance characteristics, and fault-tolerant capability of the machine are carried out. The rules governing the variation of electromagnetic performance and fault tolerance capability with slot-pole combinations are summarized. It is demonstrated that the machine exhibits best performance when the slot pole numbers are close while the fault tolerance is enhanced as the pole number increases. Finally, a prototype of an 18s14p FSCW-IPM is developed and tested to verify the correctness of the analysis.