Coreless axial flux permanent magnet (AFPM) machines are attracting increasing attention due to their compact structure and high torque density. The torque to weight ratio can be further enhanced by the use of alternate conductor materials, such as carbon nanotube (CNT), or aluminum windings in place of the copper material coils. This paper proposes a coreless AFPM synchronous motor with CNT windings. Analytical equations are developed to allow a systematic comparison of machine designs with different conductor materials. The performance of machine designs with different coil materials, namely, copper, aluminum, and CNT, is evaluated and compared. The calculations are also backed by 3-D finite-element analysis.

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Published in IEEE Transactions on Magnetics, v. 53, issue: 6.

© 2017 IEEECopyright Notice. “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/republishingthis 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 thiswork in other works.”

The document available for download is the authors’ manuscript version that is accepted for publication. The final published version is copyrighted by IEEE and available as: V. Rallabandi, N. Taran, D. M. Ionel and J. F. Eastham, “Coreless Multidisc Axial Flux PM Machine with Carbon Nanotube Windings,” in IEEE Transactions on Magnetics, vol. 53, no. 6, pp. 1-4, June 2017. doi: 10.1109/TMAG.2017.2660526

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Funding Information

The support of University of Kentucky, the L. Stanley Pigman endowment, of ANSYS, Inc. and the expert advice of Dr. Ping Zhou are gratefully acknowledged.