Expanding the operating range of permanent magnet synchronous motors by using the optimum number of phases

A holistic approach to determine the optimum number of phases m of an m-phase motor in combination with an m-leg inverter for electric vehicle applications is presented. The optimum offers a significant improvement of the torque and power by approximately 9.6% over the whole operating range in comparison to a 3-phase motor and therefore enhances the power and torque density without expanding the design parameters of the machine.