Comparison of different force calculation methods in 3D finite element modelling

Different methods for the local and total force calculation in 3D are examined. The accuracy and efficiency of these methods when applied to two dual formulations are compared through numerical examples. The local application of virtual work principle using edge elements permits calculation of local and total force in conductors as well as in magnetic materials. Concerning the equivalent sources methods (magnetising current method and magnetic charge method), they are theoretically equivalent to the Maxwell stress tensor method for total force calculation, while the numerical accuracy depends on the accuracy of the normal and tangential components of the field