Multiply connected regions in the A ¿ ¿ three-dimensional eddy-current formualtion

The low-frequency 3-dimensional (3D) eddy-current problem can be solved in certain cases using A (the magnetic vector potential) inside conductors, linked at the conductor surfaces to magnetic scaler potentials. When the regions are multiply connected due to attempts at modelling conductors which have holes (genus higher than zero), problems arise. The paper is concerned with resolving the difficulties. Three possible approaches are compared, the most promising method is used to solve a 3D multiply connected eddy-current problem for which experimental results have been obtained.