Torsional Vibration Control in Oilwell Drilling

Nonlinear output-feedback control of torsional vibrations in drilling systems

1Department of Mechanical Engineering, Eindhoven University of Technology, 5600 MB, Eindhoven, The Netherlands 2Department of Civil, Environmental & Geo-Engineering, University of Minnesota, Minneapolis, USA 3Delft Center for Systems and Control, Delft University of Technology, Delft, The Netherlands 4Well Engineering Design, Nederlandse Aardolie Maatschappij B.V. (NAM), The Netherlands 5Wells ...

Slow Resonance Ratio Control for Torsional Vibration Suppression

Vibration suppression and disturbance rejection control in torsional system is an important issue in the future motion control. Resonance ratio control is one of the most effective strategies, but the disturbance should be estimated much faster than the resonance frequency. Too fast disturbance observer causes implementation problem. To solve this problem, we propose a novel technique called "s...

Torsional Vibration of Eccentric Building Systems

The axial–torsional vibration of pretwisted beams

We investigate the coupled axial–torsional vibration of pretwisted beams. The equations of motion governing the extension, torsion, and cross-sectional warping of pretwisted beams are derived from Hamiltons principle, and the common assumptions used to simplify the equations are carefully examined through scaling analysis. Inconsistencies in previous works—such as the neglect of spatial and tim...

Experimental Evaluation of Disturbance Observer-based Vibration Suppression and Disturbance Rejection Control in Torsional System

Abstract. In the resonance ratio control, the estimation speed of the disturbance observer should have been much faster than the resonance frequency of the controlled system. However, too fast disturbance observer causes implementation problem. In this paper, we give the optimal speed of the disturbance estimation and propose a novel technique, slow resonance ratio control, which enables us to ...