Skip to Main Content
This paper discusses magnetic force imbalance and cogging torque in permanent-magnet motors under both static and dynamic rotor eccentricity. The characteristic frequencies of magnetic force imbalance and cogging torque due to rotor eccentricity can be used for fault diagnostics and quality control of permanent-magnet motors. The paper derives analytical expressions for their characteristic frequencies. The validity of the expressions has been confirmed by finite-element analyses.