Coaxial magnetic gears are a new breed of magnetic devices, which utilize the interaction of permanent magnet fields to enable torque transmission. Apart from using a numerical approach for their magnetic field analysis, an analytical approach is highly desirable since it can provide an insightful knowledge for design and optimization. In this paper, a new analytical approach is proposed to calculate the magnetic field distribution in coaxial magnetic gears. A set of partial differential equations in terms of scalar magnetic potential is used to describe the field behavior, and the solution is determined by considering the boundary constraints. The accuracy of the proposed approach is verified by comparing the field distribution results with those obtained from the finite element method.
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