Performance analysis of mechanical vibration suppression control system for motor drives with elastic load based on frequency response

One of the primary concerns in industrial motor drive systems is the suppression of the vibration caused by the elasticity of mechanical load. This paper is intended to clarify the conditions required to obtain the desirable damping by a simple control system through the analysis of the frequency response of a two-mass control system, considering the plant of left-coprime factorized form. The paper also presents some useful findings for practical design of the vibration suppression control, showing that if the above-mentioned conditions are satisfied, sufficient control performance can be obtained by a two degrees of freedom controller of the same structure as that for rigid load, and that we are compelled to reduce the stability margin in the vibration suppression control where the anti-resonant frequency and resonant frequency are near to each other.