In the process of designing and manufacturing an electrical machine, a systematic study of dimensional and material tolerances is of the utmost importance. This paper proposes a systematic method by which the effect of design specification variations on permanent magnet (PM) synchronous machine performance may be identified and quantified. The method combines design of experiments techniques, open-circuit and short-circuit physical measurements, and virtual test simulations conducted based on the recently approved IEEE Std 1812 testing guide. Three case studies, two provided by a spoke-type PM radial field machine configuration, in two designs with different electromagnetic loading, and an axial flux PM machine are discussed. It is shown that based on the output performance, out of specification tolerances for magnet remanence, steel grade, as well as dimensional variables, and stator to rotor eccentricity, may be identified under certain conditions. It is also exemplified that the ratings, magnetic loading, and configuration of the machine play critical roles and should be thoroughly considered as part of the studies.

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Published in IEEE Transactions on Industry Applications, v. 55, issue 2.

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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, D. M. Ionel, P. Zhou, M. Thiele and G. Heins, “A Systematic Study on the Effects of Dimensional and Materials Tolerances on Permanent Magnet Synchronous Machines Based on the IEEE Std 1812,” IEEE Transactions on Industry Applications, vol. 55, no. 2, pp. 1360-1371, March-April 2019. doi: 10.1109/TIA.2018.28771

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The support of University of Kentucky, the L. Stanley Pigman endowment and the SPARK program, ANSYS Inc.and Regal Beloit Corp. is gratefully acknowledged.