A Comprehensive Design Guideline of Hairpin Windings for High Power Density Electric Vehicle Traction Motors

Zou, Tianjie; Gerada, David; La Rocca, Antonino; Moslemin, Mohsen; Cairns, Alasdair; Cui, Mengmeng; Bardalai, Anuvav; Zhang, Fengyu; Gerada, Chris

Abstract

The rapidly increasing demand on power density levels of electric vehicle (EV) drive systems is pushing the boundaries of traction motor performance. Hairpin windings are becoming a popular option for EV motors due to their reduced DC losses and improved heat dissipation capability when compared to traditional random windings. In this paper, a comprehensive design approach of hairpin winding layouts is firstly presented. The flexibility and limitation of end-winding patterns is thoroughly investigated in terms of basic pin connections, special jumpers, transposition, parallel branches, terminal positions, phase shift, winding pitches as well as slot-pole combinations. To address the challenge of much reduced practical layout options with increased slot number per pole per phase, two novel hairpin winding designs are proposed. A 160kW, 18000rpm PM traction motor featuring the new winding layout with 54-slot, 6-pole is developed using a multidomain design platformwhich puts special focus on the conductor size optimization. The advantages of the designed motor are clearly revealed by comparison with the more traditional 48-slot, 8-pole counterpart. Finally, a corresponding stator prototype with the proposed hairpin winding is built to validate its manufacturability.

• Journal Article Type: Article
• Acceptance Date: Jan 24, 2022
• Online Publication Date: Feb 7, 2022
• Publication Date: 2022-02
• Deposit Date: Feb 13, 2022
• Publicly Available Date: Feb 24, 2022
• Journal: IEEE Transactions on Transportation Electrification
• Electronic ISSN: 2332-7782
• Publisher: Institute of Electrical and Electronics Engineers (IEEE)
• Peer Reviewed: Peer Reviewed
• Volume: 8
• Issue: 3
• Pages: 3578-3593
• DOI: https://doi.org/10.1109/TTE.2022.3149786
• Keywords: Electrical and Electronic Engineering; Energy Engineering and Power Technology; Transportation; Automotive Engineering
• Public URL: https://nottingham-repository.worktribe.com/output/7465906
• Publisher URL: https://ieeexplore.ieee.org/document/9706460
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