Large-scale magnetic field analysis by the hybrid finite element-boundary element method combined with the fast multipole method

This paper describes a large-scale magnetic field analysis by means of the hybrid finite element-boundary element (FE-BE) method. The hybrid FE-BE method is well-suited for solving open electromagnetic field problems that comprise movement, nonlinear media, and eddy current. In general, however, large memory and computational costs are required due to the dense blocks in the system matrix generated by the BE part of the hybrid formulation. In order to overcome the above difficulties, we introduce the fast multipole method (FMM) to the hybrid FE-BE formulation developed by ourselves. Furthermore, we propose a novel preconditioning technique suitable for the hybrid FE-BE method with the FMM. Some numerical results that demonstrate the effectiveness of the proposed approach are also presented.