Optimal design of PM motors for quasi-sinusoidal air-gap flux density

This paper presents an optimal design method for the rotor structure of permanent magnet synchronous motor by using Finite Element Method (FEM) combined with Pulse Width Modulation (PWM). The PWM technique is applied to the shape of the surface of the solid iron rotor and the magnets are buried. Calculation is straightforward and show that the radial air-gap flux density harmonics are eliminated leading to almost sinusoidal air-gap flux …