Damping Control Based on Quasi-Internal-Model for Offshore Platforms*

Abstract

This paper is concerned with the damping control problem for offshore platforms. A quasi-internal-model (QIM) control approach is proposed to vibration systems of offshore platforms with unmeasurable wave force disturbance. First, we present an approach of estimating wave force modal based on the power spectral density (PSD) function of wave force. Then a structural decoupling control to offshore platforms is proposed. Finally, A QIM compensator is designed based on the appropriate wave force modal. Numerical simulation examples show the effectiveness of the control strategy.