Influence of Rotor Eccentricity on Electromagnetic Vibration in Toroidal-Wound High-Speed Permanent Magnet Generators

Rotor eccentricity faults can cause uneven air gaps in the generator, reducing power quality and increasing vibration noise, eventually leading to abnormal operation. Especially in high-speed machines, eccentric faults are more common. This paper studies the effect of static and dynamic eccentricity faults on the electromagnetic vibration of a toroidal-wound high-speed permanent magnet generator (HSPMG). Firstly, an eccentricity mathematical model is established, and the electromagnetic characteristics under different static and dynamic eccentricities are analyzed using the numerical calculation method. The spatial and temporal distribution of the air gap magnetic field under the fault is obtained, revealing the change mechanism of the magnetic field asymmetry after the eccentricity fault. Secondly, based on Fourier time-harmonic analysis, the characteristic parameters of the electromagnetic force wave under different eccentricity rates are studied, and the characteristic parameters of the introduced electromagnetic force wave components under the eccentricity fault are obtained. Finally, the vibration acceleration of the generator stator is obtained by multi-physics field coupling and harmonic response analysis, and the vibration characteristics of the stator under static and dynamic eccentricity faults are determined. The experiment is carried out to verify the analysis.