A New Hybrid Permanent Magnet-Assisted Synchronous Reluctance Motor With Efficient Utilization of Rare-Earth Permanent Magnets

Abstract

This paper proposes a novel hybrid permanent magnet assisted synchronous reluctance machine (PMaSynRM) aiming to overcome limitations of the conventional PMaSynRM. In the conventional topology, the design of flux barriers and PMs are interdependent, causing the dimensions of PMs to be influenced by barrier geometry rather than solely adhering to magnetic requirements. Additionally, in conventional topology, the peaks of reluctance and PM torque components occur at different current angles (CAs). These are identified as major factors contributing to the inefficient utilization of PMs. The proposed topology adopts a unique approach by incorporating two distinct pole types in one lamination: SynRM poles and interior PM (IPM) poles. This configuration decouples the magnetic design of PMs and flux barriers, promoting efficient utilization of PMs. Additionally, a strategic relative displacement between the IPM and SynRM poles ensures that the peak torque generated by both pole types occurs at the same CA. The proposed design is compared to the conventional PMaSynRM, both optimized to achieve the required torque rating with minimal PM usage using response surface methodology. The results are compared in terms of PM usage, efficiency, etc. Finally, the proposed machine is manufactured, and a test set-up is provided to evaluate the simulation results.