This paper proposes a new hybrid analytical and numerical FE-based method for calculating ac eddy current losses in wire windings and demonstrates its applicability for axial flux electric machines. The method takes into account 3D field effects in order to achieve accurate results and yet greatly reduce computational efforts. It is also shown that hybrid methods based on 2D FE models, which require semi-empirical correction factors, may over-estimate the eddy current losses. The new 3D FE-based method is advantageous as it employs minimum simplifications and considers the end turns in the eddy current path, the magnetic flux density variation along the effective length of coils, and the field fringing and leakage, which ultimately increases the accuracy of simulations. Case studies of axial flux PM motors: one with concentrated windings and open slots and another one with a coreless topology, are included.

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Conference Proceeding

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Notes/Citation Information

Published in 2019 IEEE Energy Conversion Congress and Exposition (ECCE).

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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 will be available as: N. Taran, and D. M. Ionel, “A Hybrid Analytical and FE-based Method for Calculating AC Eddy Current Winding Losses Taking 3D Effects into Account,” 2019 IEEE Energy Conversion Congress and Expo (ECCE), Baltimore, MD, 2019, pp. 1-6.

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Funding Information

The support of National Science Foundation NSF Grant# 1809876, of University of Kentucky, the L. Stanley Pigman endowment, and of ANSYS Inc. is gratefully acknowledged.