BEM analysis of 3D EMC problem with consideration of eddy-current effects

The paper deals with the numerical analysis of electromagnetic shielding effects in the context of low-frequency electromagnetic compatibility problems in power installations. The indirect version of the boundary element method (BEM) is applied for the consideration of 3D eddy-current fields. Basic formulas and equations that describe the problem in question are presented. The reported numerical technique is implemented in the author´s software package BEMsolver 3D. The correctness of both the applied numerical algorithms and the computer program has been tested using measurement results taken in the laboratory. A simplified model of the transformer chamber of a 110/15 kV indoor substation has been proposed. Selected numerical results for the magnetic field strength inside the substation are exhibited. The effectiveness of the electromagnetic shield, which reduces the magnetic field strength in the control room (abutting the transformer chamber), has been computationally tested.