Comparison of Vector Potential and Extended Scalar Potential Methods and True Three-Dimensional Magnetostatic Field Calculation

This paper addresses the problem of the numerical calculation of three-dimensional magnetostatic fields. The basic equations for the vector potential method and for an extended scalar potential method are derived and the duality of both methods is shown. The superior applicability of the extended scalar potential method for three-dimensional field calculation is derived and recent results obtained for a superconducting coil are described.