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IEEE Transactions on Magnetics

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This paper presents the electromagnetic and mechanical design and analyses of a 7.67:1 gear ratio magnetic gear for a wave energy converter demonstrator. A 2-D and 3-D magnetostatic finite element analysis (FEA) was conducted to maximize the mass torque density. To increase torque without increasing the diameter a unique dual-stack rotor topology was used along with a twelve-segment per pole-pair inner rotor Halbach array and a four-segment per pole-pair outer rotor Halbach topology. The eddy current loss within the magnetic gear was mitigated by using laminated magnets and a low-loss electrical steel. The experimentally tested magnetic gear had a peak torque of 1796.8 N∙m which corresponds to an active region volumetric and mass torque density of 221.1 N∙m/L and 105.74 N∙m/kg, respectively. The efficiency at rated speed and maximum torque was measured to be 95%. A new in-plane eddy current loss mechanism was identified as being a primary reason for the measured electrical losses being higher than initially calculated.


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This is the author’s version of a work that was accepted for publication in IEEE Transactions on Magnetics, Changes resulting from the publishing process, such as peer review, editing, corrections, structural formatting, and other quality control mechanisms may not be reflected in this document. Changes may have been made to this work since it was submitted for publication. A definitive version was subsequently published in IEEE Transactions on Magnetics, 2022, doi: 10.1109/TMAG.2022.3199580.



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