Design and Analysis of a Novel Asymmetric-Stator-Pole Dual-PM Vernier Machine

In this paper, a novel dual-permanent-magnet (PM) vernier machine (DPMVM) with asymmetric-stator-pole (ASP) configuration was proposed and analyzed. The key feature of this design is the use of a combination of a stator with NdFeB magnets and a rotor with ferrites. In addition, the consequent-pole (CP) structure, auxiliary slots, Halbach array, and overhang structure have been introduced to improve the PM utilization and torque density. Based on magnetomotive force permeance model, the ASP design of proposed machine introduces additional harmonics to produce torque when compared to conventional flux reversal machine (FRM). Meanwhile, a comparative study in terms of electromagnetic performance of the conventional FRM, CP-FRM with ASP design, and proposed ASP-DPMVM was carried out based on finite element method and multi-objective optimization, and the effect of different overhang structures on torque characteristic of proposed machine was investigated. Finally, a prototype of proposed ASP-DPMVM was fabricated and tested to validate the simulations.