Vibration of a Motor on Viscoelastic Foundation Due to Whirling of the Shaft With Consideration of Electromagnetic Forces

Abstract

This paper discusses bending vibration characteristics of a rotating shaft of a motor with consideration of the electromagnetic sucking force which acts on a rotor caused by the narrow electromagnetic field between a stator and the rotor. The dynamic response of the motor under the action of the whirling load of the shaft has been analyzed systematically by considering both the translational and rotary motions of the motor. In the analysis the transfer matrix method is used to obtain the response of the shaft. The equation of longitudinal vibrations of a viscoelastic body is applied to the analysis of the viscoelastic foundation under the assumption of the structural damping. Numerical calculations have been carried out for the natural frequencies, the response of the motor shaft, and the response and the transmissibility of the motor.