This paper presents a systematic design optimization and experimental study of coreless axial-flux permanent magnet (AFPM) machines with wave winding printed circuit board (PCB) stators. Existing PCB winding configurations are briefly reviewed and compared to serve as a performance reference. A new concept –the “macro coil”– is proposed to model PCB stator windings in 3D finite element analysis (FEA) to facilitate large-scale multi-objective optimization with the winding eddy current losses evaluated in each design candidate. The detailed trace-by-trace model for a selected optimal design is then built to check the voltage difference between parallel paths and the resulting circulating currents. A prototype with two PM rotors and a central stator comprising multiple stacked PCBs has been fabricated and tested on a customized test fixture for experimental validation.

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Conference Proceeding

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Notes/Citation Information

Published in Proceedings, IEEE Energy Conversion Congress and Exposition.

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The document available for download is the authors’ manuscript version accepted for publication. The final published version is copyrighted by IEEE and available as: Han P., Lawhorn D., Chulaee Y., Lewis D., Heins G., and Ionel D. M., “Design Optimization and Experimental Study of Coreless Axial-flux PM Machine with Wave Winding PCB Stator,” Proceedings, IEEE Energy Conversion Congress and Exposition (ECCE), Vancouver, Canada, pp.1-6, Oct 2021.

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Funding Information

This material is based upon work supported by the National Science Foundation (NSF) under Grant No. #1809876. Any opinions, findings, and conclusions or recommendations expressed in this material are those of the authors and do not
necessarily reflect the views of the NSF. The support of the University of Kentucky, the L. Stanley Pigman Endowment, of Ansys, Inc., and of Regal Beloit Corp. is also gratefully acknowledged.