Optimization and Comparison of 1MW-Class PM Motors for Aircraft Propulsion Using Litz Wire and Hairpin Windings

Huynh, Anh Thanh; Huang, Hailin; Jiang, Jianan; Zou, Tianjie; Gerada, David; Yang, Tao; Gerada, Chris

doi:10.1109/tmag.2025.3547237

Optimization and Comparison of 1MW-Class PM Motors for Aircraft Propulsion Using Litz Wire and Hairpin Windings

Huynh, Anh Thanh; Huang, Hailin; Jiang, Jianan; Zou, Tianjie; Gerada, David; Yang, Tao; Gerada, Chris

Authors

Dr ANH HUYNH ANH.HUYNH@NOTTINGHAM.AC.UK
RESEARCH FELLOW

Dr HAILIN HUANG HAILIN.HUANG@NOTTINGHAM.AC.UK
RESEARCH FELLOW

Ms JIANAN JIANG JIANAN.JIANG1@NOTTINGHAM.AC.UK
RESEARCH ASSOCIATE

Dr TIANJIE ZOU TIANJIE.ZOU@NOTTINGHAM.AC.UK
ASSISTANT PROFESSOR

Professor DAVID GERADA D.Gerada@nottingham.ac.uk
PROFESSOR OF ELECTRICAL ENGINEERING

Professor TAO YANG TAO.YANG@NOTTINGHAM.AC.UK
PROFESSOR OF AEROSPACE ELECTRICALSYSTEMS

Professor CHRISTOPHER GERADA CHRIS.GERADA@NOTTINGHAM.AC.UK
PROFESSOR OF ELECTRICAL MACHINES

Abstract

Choosing the right winding technology is key to maximizing power density and efficiency in electric aircraft propulsion. This paper presents a two-level optimization strategy to evaluate Litz wire and hairpin winding configurations in two 1 MW-class PM machines, each with a 5-stage Halbach array and a 72-slot/12-pole configuration. The global optimization (GO) stage analyzes their impact on power density, loss distribution, and efficiency. Results show that hairpin winding increases power density by reducing active mass but suffers from higher AC copper losses. To address this, an updated motor constant (Km ) serves as a fitness function in a Genetic Algorithm (GA) during the local optimization (LO) stage, refining the hairpin winding and stator slot design to reduce losses and enhance efficiency. Finite Element Analysis (FEA) validates the performance and effectiveness of the proposed method.

Citation

Huynh, A. T., Huang, H., Jiang, J., Zou, T., Gerada, D., Yang, T., & Gerada, C. (2025). Optimization and Comparison of 1MW-Class PM Motors for Aircraft Propulsion Using Litz Wire and Hairpin Windings. IEEE Transactions on Magnetics, https://doi.org/10.1109/tmag.2025.3547237

Journal Article Type	Article
Acceptance Date	Feb 24, 2025
Publication Date	Mar 3, 2025
Deposit Date	Mar 12, 2025
Publicly Available Date	Mar 14, 2025
Journal	IEEE Transactions on Magnetics
Print ISSN	0018-9464
Electronic ISSN	1941-0069
Publisher	Institute of Electrical and Electronics Engineers
Peer Reviewed	Peer Reviewed
DOI	https://doi.org/10.1109/tmag.2025.3547237
Keywords	Aircraft Applications, PM machines, Litz Wire, Hairpin Winding, High Power Density, Optimization.
Public URL	https://nottingham-repository.worktribe.com/output/46312991
Publisher URL	https://ieeexplore.ieee.org/document/10908992