A Parameterized Linear Magnetic Equivalent Circuit for Air Core Radial Flux Coaxial Magnetic Gears with Halbach Arrays

This paper describes a systematic way to create a 2D linear magnetic equivalent circuit (MEC) from node cells in a radial flux coaxial magnetic gear with Halbach arrays and without back irons. Three base designs are used to validate the accuracy of the MEC against a nonlinear 2D FEA in terms of torque and air gap flux densities. Guidelines based on each design's pole arcs are presented for distributing the node cells inside the inner ring of magnets and outside the outer ring of magnets. Based on these guidelines, an extensive parametric study is performed to compare the MEC and FEA results. The MEC is able to very accurately track design parameter trends. Even for the worst cases, the MEC predicts a torque within 6.9% of the FEA for a relatively coarse node cell mesh and within 4.2% with a finer mesh. However, the MEC is significantly faster than the FEA. With the coarser mesh, the MEC is almost two orders of magnitude faster than the FEA. Thus, this systematic linear MEC can be a useful tool for performing rapid initial optimizations.