Magnetic Pole Optimization of Sinusoidal Pole-shaping Surface-mounted Multi-phase Permanent Magnet Synchronous Motors

To compare the optimization effects of air gap flux density between the eccentric pole shaping(EPS) and the sinusoidal pole shaping(SPS) in surface-mounted multi-phase permanent magnet synchronous motors (PMSMs), the air gap flux density under two pole shaping models are calculated by using the control variable method. Firstly, the mathematical models of permanent magnets (PM) under two different pole cutting modes are established by equivalent surface current method. Secondly, the air gap flux density is calculated by subdomain method. Thirdly, the electromagnetic performance of the multi-phase PMSM with different pole shaping modes is compared through controlling the PM volume and the minimum air gap length. Finally, an 10kW surface-mounted nine-phase permanent magnet synchronous motors is simulated to verify the calculation results.