Analytical surface charge method for rotated permanent magnets : boundary element method comparison and experimental validation

This paper is concerned with the analytical calculation of the interaction force between two permanent magnets (PMs) under relative rotation by means of the surface charge method, taking into account the non-unity relative permeability of the PMs. This model combines high accuracy and a short calculation time. As the considered PM configuration is a free-space, unbounded problem, the results from the surface charge method are compared to its numerical counterpart, the Boundary Element Method (BEM). The analytical expressions were validated by means of the measurement results obtained from a 3-D printed test setup.