Electrical Machine Slot Thermal Condition Effects on Back Iron Extension Thermal Benefits

Zhang, Fengyu; Gerada, David; Xu, Zeyuan; Tighe, Chris; Zhang, He; Yan, Liang; Gerada, Chris

Abstract

The slot thermal condition is critical for thermal management of high-performance electrical machines, due to the high heat losses and poor heat transfer ability within the slot. With a part of the back iron projected radially downward into the slot, back-iron extension (BIE) shortens the heat dissipation path from the slot coil to the back iron and was proved to be an effective thermal improvement technique. The relationship between BIE thermal benefits and various electrical machines' parameters remains to be investigated. Based on an existing concentrated-wound machine, the relationship between the equivalent slot thermal conductivity (ESTC) and the BIE effectiveness is researched in this article. Utilizing a developed 3-D thermal model, the ESTC effects on the temperature reduction with BIE are indicated with simulation results and verified with experimental tests. BIE is reported to provide temperature reductions ranging from 48 °C down to 18 °C across the plausible range of ESTC values considered. Guidelines are given in the final part to suggest the situations under which BIE is more effective.

Citation

Zhang, F., Gerada, D., Xu, Z., Tighe, C., Zhang, H., Yan, L., & Gerada, C. (2021). Electrical Machine Slot Thermal Condition Effects on Back Iron Extension Thermal Benefits. IEEE Transactions on Transportation Electrification, 7(4), 2927-2938. https://doi.org/10.1109/tte.2021.3085822

• Journal Article Type: Article
• Acceptance Date: May 18, 2021
• Online Publication Date: Jun 4, 2021
• Publication Date: 2021-12
• Deposit Date: Jun 6, 2021
• Publicly Available Date: Jun 17, 2021
• Journal: IEEE Transactions on Transportation Electrification
• Electronic ISSN: 2332-7782
• Publisher: Institute of Electrical and Electronics Engineers
• Peer Reviewed: Peer Reviewed
• Volume: 7
• Issue: 4
• Pages: 2927-2938
• DOI: https://doi.org/10.1109/tte.2021.3085822
• Public URL: https://nottingham-repository.worktribe.com/output/5649274
• Publisher URL: https://ieeexplore.ieee.org/document/9446913
• Additional Information: © 2021 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.