Effect of Rotor Eccentricity and Magnetic Circuit Saturation on Acoustic Noise and Vibration of Single-Phase Induction Motors

The Unbalanced Magnetic Pull and Its Effects on Vibration in a Three-Phase Generator With Eccentric Rotor

“…Few authors have tried to obtain the analytical expression of the UMP for any pole-pair machine, and only a few authors have studied the vibratory characteristics of the rotor system due to the UMP. They are Belmans et al [10], Zhu et al [11], and Fruchtenicht et al [4]. Belmans et al [10] studied the in#uence of the UMP on the radial stability of the shaft in a two-pole machine.…”

“…They thought that owing to the UMP, an electromagnetically induced spring coe$cient and damping coe$cient were generated which resulted in the decrease of the natural frequency and the change of the total damping ratio. Zhu et al [11] studied the e!ect of the rotor eccentricity on acoustic noise and vibration of the single-phase induction motors. Fruchtenicht et al [4] investigated the self-excited transverse vibration of a four-pole machine due to the UMP.…”

Prediction of the electromagnetic noise of an asynchronous machine using experimental designs

“…The method used and well detailed by Zhu and Howe [12], but also by Timar [9] and Breahna and Viarouge [3], to identify modes and resonances frequencies, seems to be more appropriate to our study and more general compared to the example developed in the previous section.…”

“…The expression (12) shows that the frequency contents of forces is composed of packages of three lines located at krN r pf R − 2f s , krN r pf R and krN r pf R + 2f s .…”

Circular whirling and stability due to unbalanced magnetic pull and eccentric force

“…They concluded that spring and damping coefficients induced by electro-magnetic field resulted in the decrease of natural frequency and the change in total damping. Zhu and Howe [7] studied the effect of rotor eccentricity on acoustic noise and vibration of single-phase induction motors. Fruchtenicht et al [2] investigated the self-excited transverse vibration of a four-pole machine due to UMP.…”