3-D magnetostatic field calculation by a single layer boundary integral equation method using a difference field concept

For an accurate analysis of three dimensional linear magnetostatic problems , a new boundary integral equation formulation is presented. This formulati on adopts difference magnetic held concept and uses single layer magnetic s urface charge as the unknown. The proposed method is capable of eliminating numerical cancellation errors inside ferromagnetic materials. In addition, computing time and storage memory are reduced by 75% in comparison with th e reduced and total scaler potential formulations. Two examples are given t o show its efficiency and accuracy.