Prediction method of vibration response of electric motor considering casing as dynamic stiffness

Abstract

Recently there is a great demand for reduction in size and weight of industrial motors. Therefore sometimes the motor casing has lower stiffness than conventional model and this stiffness becomes equal to the bearing stiffness. In this case, we need to consider support structure stiffness when we calculate the shaft vibration of the motor. In this paper, modeling the casing as dynamic stiffness, a vibration response prediction method was applied to the finite element method of rotating dynamics model. We also analyzed the effect of coupling stiffness between bearings and evaluated calculation error.