Comparison of the force computation using the vector and scalar potential for 3D

Two ways of secondary field quantities and force calculation are discussed and compared. For the magnetostatic case both approaches, scalar potential and vector potential method can be applied. The scalar potential formulation have proved to be very effective and finally the normal component of the magnetic flux density can be computed. If the vector potential method is used, it is necessary to determine the tangential component of the magnetic field strength as the secondary field value. The paper describes the method of the calculation of 3D static fields using finite difference solutions. For calculation of forces the Maxwell stress is used.