Multi-phase permanent magnet motor drives

In this paper, a new five-phase brushless permanent magnet motor is proposed. The proposed motor has concentrated windings so the produced back-EMF is almost trapezoidal. The motor is supplied with the combined sinusoidal plus third harmonic of currents. For presenting the superior performance of the proposed five-phase motor, its three and five-phase counterparts are also analyzed. By changing the number of turns and slot width, the amount of copper and iron are kept constant in all motors so that the copper and core losses are almost the same. Finite element method is used for studying the flux density and calculating the developed static torque. Also, the developed torque is obtained using the mathematical model in d-q frame. The average torque and the torque ripple of all cases are presented and compared.