Axial flux permanent magnet (AFPM) motors are suitable options for solar-powered vehicles due to their compact structure and high torque density. Furthermore, certain types of AFPM machines may be configured without stator cores, which eliminates associated losses and cogging torque and simplifies the manufacturing and assembly. This paper examines two machine designs for use in the solar-powered vehicle of the challenger class-a single rotor, single stator conventional AFPM machine, and a coreless AFPM machine with multiple stator and rotor disks. The response surface methodology (RSM) is utilized for the systematic comparison of the conventional and coreless topologies and to select the optimum designs among several hundreds of candidates. Designs with minimum losses and mass producing required torque with larger air-gap are favored. The performance of the selected designs has been studied via three-dimensional finite element analysis (FEA). The FEA parametric modeling methodology is validated by measurements on three AFPM machines of the conventional and coreless type.

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Published in IEEE Transactions on Industry Applications, v. 54, 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: N. Taran, V. Rallabandi, G. Heins and D. M. Ionel, “Coreless and Conventional Axial Flux Permanent Magnet Motors for Solar Cars,”IEEE Transactions on Industry Applications, Vol. 54, No. 6, pp. 5907-5917, 2018. doi: 10.1109/TIA.2018.285512

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Funding Information

The financial support of University of Kentucky, the L. Stanley Pigman endowment and the SPARK program, of ANSYS Inc. for the software and of Arnold Magnetic Technologies for building the PM prototype rotor is gratefully acknowledged.