Abstract
This paper deals with the quenching problem of electromagnetic vibration of the motor stator with imperfections at the resonant frequency using a pair of dynamic absorbers. The iron stator of motor is modeled by a circular ring with single or two imperfect masses, and dynamic absorbers are installed on the outside of the circular ring to quench the forced vibration caused by the rotating distributed electromagnetic force. The solutions of forced vibration are obtained by the theoretical analysis. The following were made clear; (1) As imperfect mass reduces the natural frequency of the motor stator, resonant frequency becomes low. (2) In the case where the weight of two imperfect masses are heavy, the closer the angle at which two imperfect masses forms, is close to the angle between the loop and node of the mode that is to be quenched, the resonant amplitude is reduced. (3) By installing single dynamic absorber and single imperfect mass, and by setting an angle between the loop and node of the mode to be quenched, quenching is possible. (4) Even if imperfections exist, installing a pair of dynamic absorbers that make an angle equal to the one between the loop and node of the mode to be quenched, makes the motor stator quenched perfectly.
