Influence of 2D and 3D meshes in FE computation of eddy-current losses in surface PMSMs

This paper investigates the influence of finite-element (FE) mesh when computing eddy currents in magnets of a permanent-magnet synchronous machine excited with pulsating currents (such as pulse-width modulation). 3D computations with globally and locally varying mesh densities are performed and results are compared with a reference (fine-mesh) case. It turns out that a global increase of mesh density has the most important impact on the result accuracy. The accuracy of 2D FE computations is also discussed for different stack lengths. It is shown that the use of a correction factor based on analytical approach can significantly increase accuracy for relatively short stack lengths.