Analysis of permanent magnet synchronous motors with integer-slot and fractional-slot windings

This paper examines torque ripple, cogging torque, and d-axis and q-axis reactances variation in permanent magnet synchronous motors (PMSMs). Effect of number of poles on electromagnetic motor torque (including cogging torque), and d- and q-axis reactance, has been analyzed for two different PMSM configurations having the same envelop dimensions and output requirements. Finite element technique is used for computation of the machine characteristics. Maxwell stress tensor is used to find the torque.