Comparative Study of Stator-Consequent-Pole Permanent Magnet Machines With Different Stator-Slot Configurations

This paper presents a comparative study of the stator-consequent-pole permanent magnet (SCPPM) machines with different stator-slot configurations, i.e., semi-closed slot (SCS) and closed slot (CS). The machine topologies and working mechanism are introduced first. The air-gap field distributions and dominant harmonics contributing to the torque generation corresponding to different stator-slot-opening ratios are evaluated. Then, the six-stator-slot SCS and CS configurations with different rotor-pole pair combinations are optimized by the multi-objective genetic algorithm. In addition, the major electromagnetic characteristics of the optimized 6-/11-pole SCPPM machines having SCS and CS structures are comparatively investigated by the finite-element (FE) analysis. Finally, an SCPPM machine prototype is manufactured and tested to verify the FE analyses.