Calculation of 3D eddy current fields using both electric and magnetic vector potential in conducting regions

Most papers concerning the calculation of 3D eddy current problems are using a combination of a vector potential and a scalar potential to solve the electromagnetic field in conducting regions. This paper presents the A/spl I.oarr/T/spl I.oarr/ formulation using both the magnetic vector potential A/spl I.oarr/ and the electric vector potential T/spl I.oarr/ for the eddy current regions. Since nodal vector potentials with continuous normal components have accuracy problems at interfaces of regions with different permeabilities, edge elements are used for both potentials. The advantages of the presented formulation compared to the mentioned well-known formulations are described in detail. The formulation is applied on the computation of the 3D time-harmonic eddy current field of an induction furnace and is compared to other formulations as well.