DC current distributions and magnetic fields using the T-omega edge-element method

When steady currents flow in solid conductors, the current distributions are not known in advance, and a 3D finite-element analysis of the magnetostatic fields must also involve an analysis of the currents. To find the currents, either of two potentials can be used: the electric scalar potential or a vector potential T for the current density. The scalar potential has the disadvantage of producing a current density that is only approximately solenoidal, and is therefore incompatible with Ampere´s Law for the magnetic field. The vector potential gives solenoidal currents. It may conveniently be found by applying the T-Ω edge element method, an existing method for eddy current problems, in one of two ways: setting the frequency so low that the DC solution is obtained; or solving first for T, then for Ω. Either way, both the current distribution and the magnetic field are obtained, and the solution is ideally suited for subsequent transient analysis. Results from three test problems confirm the validity of the method