A new method to compute eddy current losses by the finite elements method

A new method to compute eddy currents and their associated losses in permanent magnet synchronous machines is presented in this paper. The method is based on the evaluation of the time variation of the magnetic vector potential without having to solve a time variant Poisson equation. The time variation is simulated by a number of static solutions for different displacement angles between the stator and the rotor over one slot pitch interval. Then the time varying magnetic vector potential for each node and hence the eddy current density and its associated loss are obtained for each element. Results obtained by this technique are compared with a well established method and also with experimental results obtained from a canned high field permanent magnet synchronous motor. These results show a high degree of validity when compared with those obtained experimentally.