Abstract
We investigate the characteristics of cogging torque and unbalanced magnetic force (UMF) due to the interaction between magnetization of permanent magnet (PM) and stator eccentricity in PM motors. We numerically show that the third harmonic of PM magnetization interacts with stator eccentricity to decrease the amplitude of pole harmonic of the cogging torque and UMF as well as to increase the amplitude of the least common multiple harmonic of pole and slot numbers in the PM motors. We experimentally verify the effect of the third harmonic of PM magnetization on UMF and acoustic noise in the PM motors with stator eccentricity.
