Nonstationary Robust Vibration Control Considering Scaled Structured and Unstructured Uncertainties (Application to Vibration Control of Wire Changing Its Length)

Abstract

This paper presents a synthesis method of nonstationary robust controller considering uncertainties of time-varying object such as variation of parameter and spillover due to ignored high order modes of object. The variation of parameter is experessed by a scaled structured uncertainty in the time domain. Meanwhile, the influence of spillover is given as a unstructured uncertainty in the frequency domain. In this research, a nonstationary robust vibration controller considering both uncertainties is designed by solving a time-varying Riccati equation derived from a differential game type criterion function. The proposed control method is applied to the transverse vibration control of wire changing its length. Through numerical calculations, the reduction performance of the proposed controller is verified and the advantage with respect to the robustness for the uncertainties is demonstrated.