Adaptive mesh generation within nonlinear iterative calculations for analyses of electric machines

In this paper, we propose a novel algorithm of adaptive mesh generation for the nonlinear finite-element analysis of electric machines. An auto-mesh generation technique is applied at each nonlinear iterative step with the error estimation of the field distribution obtained by each nonlinear iterative calculation. The flux density and the permeability of the new elements are defined by interpolating calculations from previous mesh in order to continue the nonlinear iteration. The proposed method is applied to the analyses of several motors. It is clarified that the method gives nearly identical results of a conventional adaptive meshing method while the calculation time is reduced to less than 1/10 in most cases.