Influence of Airgap Length on Performance of High Power PM-Assisted Syn-Rel Machines

Zou, Tianjie; Gerada, David; Walker, Adam; Vakil, Gaurang; La Rocca, Salvatore; La Rocca, Antonino; Paciura, Krzysztof; Barden, Richard; Ernest, Emil; Zhu, Shaohong; Qayyum, Naila; McQueen, Alastair; Bardalai, Anuvav; Ram Kumar, R. M.; Marfoli, Alessandro; Gerada, Chris

Abstract

In recent years, synchronous reluctance (Syn-Rel) machines are research hotspots in variable speed motor drives due to their robust rotor structure and wide constant power speed range (CPSR). More practically, when kVA limitation is considered, embedded permanent magnets (PMs) have been widely adopted in Syn-Rel rotors to further increase power density as well as power factor. In this paper, the authors have investigated the potential of PM-assisted Syn-Rel machine to be the next generation electrical propulsion motor topology for automotive application, with special attention put on a key geometric parameter, i.e., airgap length. In MTPA region, the influence of airgap length on different torque components has been analyzed in detail based on the frozen permeability method. In field weakening region, the variation trend of several key performance such as peak power, iron loss and torque ripple have been investigated along with airgap length. It is found that with specifically high level of electric and magnetic loading, there exists optimal value of airgap length to achieve high power density based on specific cooling and kVA limitation. Numerical FEA and experimental tests are associated to validate the conclusions.

• Conference Name: 2020 IEEE Energy Conversion Congress and Exposition (ECCE 2020)
• Conference Location: Detroit, MI, USA
• Start Date: Oct 11, 2020
• End Date: Oct 15, 2020
• Acceptance Date: May 1, 2020
• Online Publication Date: Oct 30, 2020
• Publication Date: Oct 11, 2020
• Deposit Date: May 14, 2021
• Publicly Available Date: Jul 5, 2021
• Publisher: Institute of Electrical and Electronics Engineers
• Pages: 1357-1363
• Series Title: IEEE Energy Conversion Congress and Exposition (ECCE)
• Series ISSN: 2329-3748
• Book Title: 2020 IEEE Energy Conversion Congress and Exposition (ECCE)
• ISBN: 9781728158273
• DOI: https://doi.org/10.1109/ecce44975.2020.9235712
• Public URL: https://nottingham-repository.worktribe.com/output/5530133
• Publisher URL: https://ieeexplore.ieee.org/document/9235712
• Additional Information: © 2020 IEEE. Personal use of this material is permitted. Permission from IEEE must be obtained for all other uses, in any current or future media, including reprinting/republishing this material for advertising or promotional purposes, creating new collective works, for resale or redistribution to servers or lists, or reuse of any copyrighted component of this work in other works.