FEM/BEM Hybrid Method for Magnetic Field Evaluation Due to Underground Power Cables

This paper is a contribution to the evaluation of electromagnetic fields due to underground power cables. Open boundary 2-D problems may be treated combining the finite element method (FEM) inside a region surrounded by a regular (cylindrical) fictitious surface with a semi-analytical boundary element method (BEM) to describe the field outside this region. For the outside region, a generalization of Pollaczek´s solution is applied, taking into account eddy currents in the soil and the proximity effect between the soil/air plane surface and the cylinder fictitious surface with finite radius. The method is validated by using typical underground power cables where analytical methods may be applied accurately.