Coreless axial flux machines are of interest because of the absence of stator core losses and cogging torque. These machines generally employ concentrated windings. One of the challenges with such a winding is that the torque producing MMF component that corresponds to the fundamental of the magnet excitation is accompanied by substantial asynchronous components. These harmonics cause losses in the rotor core and magnets, which can become significant at high speeds. This paper proposes a new multilayer winding arrangement to eliminate the non-torque producing MMF components. This winding is applied to a 12-coil 16-pole coreless axial flux machine. The efficacy of the winding is established by 3-D finite-element analysis.

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

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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, and D. M. Ionel, “Multilayer Concentrated Windings for Axial Flux PM Machines,” in IEEE Transactions on Magnetics, vol. 53, no. 6, pp. 1-4, June 2017, Art no. 8103104. doi: 10.1109/TMAG.2017.2661312

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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.