Torque Component Quantification and Design Guideline for Dual Permanent Magnet Vernier Machine

A quantitative analysis and design guideline for dual-permanent-magnet Vernier machine (DPMVM) are presented in this paper. First, by winding factor analysis for dominant air-gap harmonics, torque components excited by stator PMs and rotor PMs are quantified, which reveals that, in DPMVM, the rotor PMs essentially have higher torque generation ability than stator PMs, due to the effective utilization of fundamental PM harmonic without flux modulation. Furthermore, mutual influence between dual PM sources is analyzed. It is revealed torque contribution of stator PMs is unilaterally affected by design parameters of rotor PMs. Finally, a design guideline is provided for DPMVM, considering the design priorities of dual-PM sources. Finite element simulation and prototype experiments prove the validity of the theoretical analysis.