Multi-Harmonic-Layered Design and Optimization of a Flux-Concentrated PM Vernier Motor Considering Harmonic Sensitivity

In this paper, an optimization design is carried out for a flux-concentrated permanent magnet vernier (FC-PMV) motor, in which the optimization is realized from the perspective of air-gap harmonics. And the torque, torque ripple, and core loss are selected as the optimization objectives for the FC-PMV motor. Based on the relationships between optimization objectives and air-gap harmonics, a multi-harmonic-layered method is proposed purposely. The key of the research is to obtain the contributions of air-gap harmonics to motor performances and realize the layering of air-gap harmonics. Hence, the harmonic sensitivity is first calculated to obtain respective sensitive harmonics, which is the basis for the layering. And then the selected sensitive harmonics are designed in layers for different performance objectives, where joint and independent designs are implemented respectively. In addition, the performances of torque, torque ripple, and core loss of the FC-PMV motor are investigated. It is indicated that the change in the contribution of target harmonics in each layer brings about performance improvements. Finally, the prototype motor is built for validating the feasibility and effectiveness of the FC-PMV motor and design method.