Investigation of iron loss in flux-switching PM machines

The iron loss in flux-switching permanent magnet (FSPM) machine is investigated by the finite element method in this paper. Since the permanent magnets in a FSPM machine are on the stator, rather than on the rotor as in the conventional PM machines, the iron loss exists not only in the stator but also in the rotor, while its calculation becomes more difficult due to complex flux density waveforms. A more accurate model for the iron loss calculation is proposed for the FSPM machine, with due consideration of the influence of operation conditions, including constant torque and flux-weakening. Finite element predicted open-circuit flux waveforms and iron loss are validated experimentally.