Electromagnetic Vibration Analysis of PMSMs Considering Static Rotor Eccentricity

Rotor eccentricity is a common fault in electrical machines that can cause motor damage, degrade electromagnetic performance, and increase noise and vibration levels. This study investigates the impact of static rotor eccentricity on the electromagnetic performance and radial vibration behavior of permanent magnet synchronous motors (PMSMs). First, a 2D finite element model (FEM) for electromagnetic analysis was developed to compare PMSMs under a healthy condition and those affected by static rotor eccentricity (SE). The analysis examined how SE influences the air-gap magnetic flux distribution as well as the resulting tangential and radial magnetic forces under both noload and load conditions. Second, an accurate 3D finite element structural model was employed to evaluate the stator's vibration response under various magnetic force excitations, including both radial and tangential forces applied to the stator teeth. Finally, the vibration responses of the healthy and eccentric cases were compared. The results indicate that static eccentricity significantly amplifies vibration levels. Additionally, tangential magnetic forces play an important role in the overall vibration response of PMSMs. Therefore, for more accurate vibration prediction, both rotor eccentricity and tangential electromagnetic forces should be taken into account.