Efficient finite element solution of multipath eddy current problems

This paper presents a new formulation for the classical steady state multipath eddy current problem in two dimensions. The method consists of obtaining the magnetic vector potential and the source current density from the projective soiution of the diffusion equation and Ampere's law given the total measurable current flowing in the conductors. The method differs from previous work because it treats the source current density as an unknown and allows a one step solution of the problem. It is shown that the power system constraints are embedded in a natural way within the electromagnetic field model through the total measurable excitation current. It is also shown that this procedure is readily included in the finite element discretization process and leads to a simple and elegant solution. The technique is illustrated by way of a skin effect solution of an inverse T slot problem, four conductor busbar arrangement, and a sheath embedded power cable.