Improvement of Disturbance Suppression Based on Disturbance Observer

[出版社版](c)2006 IEEE. Personal use of this material is permitted. However, permission to reprint/republish this material for advertising or promotional purposes or for creating new collective works for resale or redistribution to servers or lists, or to reuse any copyrighted component of this work in other works must be obtained from the IEEE.This research focuses on improvement of disturbance suppression even under existence of observation noise. Disturbance observer is an effective tool to estimate and compensate disturbance. There is a problem, however, that it cannot accomplish desired disturbance suppression when a large observation noise exists. In this research, a method with which influence of disturbance can be suppressed greatly even with a large observation noise is proposed. The authors focus on an LPF used in velocity calculation. The method is proposed based on the analysis on the characteristics and mechanism of disturbance suppression in disturbance observer with a focus on its cut-off frequencies. In the method, the cut-off frequency of disturbance observer is set higher than that for velocity calculation. Validity of the proposal was confirmed in theoretical analysis, simulation, and experiment