A skin depth-independent finite element method for Eddy current problems

A Finite Element Method based on an exponential shape function is introduced for eddy current problems. It is shown that for 1-D problems in a cartesian geometry, the resulting Finite Element equations are identical to difference equations derived previously using singular perturbation theory and numerical fitting techniques. The theory, as well as application to several 1-D problems, shows that the technique is strongly skin depth-independent; i.e. the results obtained by the method are uniformly accurate for small and large skin depth problems.