A 3D finite element analysis of large-scale nonlinear dynamic electromagnetic problems by harmonic balancing and domain decomposition

The dual-primal finite element tearing and interconnecting (FETI-DP) method is applied together with the harmonic balance method and the fixed-point (FP) method to improve the efficiency of three-dimensional finite element analysis of large-scale nonlinear dynamic electromagnetic problems. The FETI-DP method decomposes the original problem into smaller subdomains problems. Combined with parallel computing techniques, the total computation time can be reduced significantly. To account for nonlinear B-H characteristics, the FP method is applied together with the polarization formulation. Because the FP method assumes a constant reluctivity, it decouples the systems of different harmonics. The FETI-DP method can then be applied to speed up the simulation of each harmonic in each FP iteration. Two benchmark problems and a three-phase inductor are simulated by the proposed method to validate the formulation and demonstrate its performance.