In this paper, a general method of three dimensional vector potential solution for nonlinear magnetostatic field problem by means of the finite tetrahedral element method is presented.

If using the scalar potential instead of the vector potential to analyze the current-carrying regions in a 3d magnetostatic field, the computing time can be greatly reduced.

The 3d finite element vector potential equations of non-linear anisotropic magnetostatic field have been derived in a pithy style by dyadic analysis.