Analysis of a Complementary Dual-Stator Vernier Machine With Reduced Non-Working Harmonics for Low-Speed Direct-Drive Applications

This article presents a comprehensive analysis of a novel complementary dual-stator Vernier machine (DSVM) with improved performance. In contrast to conventional DSVMs, the proposed machine employs a unique configuration featured by a complementary stator design alongside phase-shifted dual stator winding. Therefore, the symmetry of flux distribution is improved, and the non-working even order harmonics produced by the armature winding are effectively reduced. Consequently, the power factor is notably improved to 0.91, and the unbalanced force is reduced by 60.14% compared to the conventional DSVM. The electromagnetic performance, mechanical structure and thermal analysis are well investigated by using finite element analysis (FEA). In addition, the temperature rise under the rated load condition with natural cooling is safe, and the mechanical strength is proved to be sufficient, which validates the feasibility of the proposed novel design. Finally, a prototype is fabricated, and the performance is tested to verify the feasibility of the proposed design.