Starting Torque of Single-Phase Flux-Switching Permanent Magnet Motors

In this paper, the starting torque of the 4/2 single-phase FSPM motor is investigated by finite element analysis, and validated experimentally. It is shown that the rotor pole-arc can significantly affect the electromagnetic torque and starting capability, since it also affects the amplitude and waveform of the cogging torque, and, therefore, the number and angular location of stable rotor rest positions. Thus, the rotor pole-arc is a key design parameter which must be optimized. Both 2D and 3D finite element analyses show that a pole-arc of 80deg results in the most favourable torque-displacement characteristic, as has been confirmed experimentally.