Vibration mitigation of floating offshore wind turbines using nonlinear model predictive control

Abstract

 This work presents a comparison between a standard tuned mass damper (TMD) and a semi-active strategy based on nonlinear model predictive control (NMPC) for oscillation mitigation in a floating offshore wind turbine (FOWT). The objective is to evaluate the capability of both solutions to reduce the dynamic response of the platform and tower under transient conditions. The results show that the NMPC-based design increases the effective damping of the system and achieves a faster reduction of platform pitch oscillations and tower-top displacement. Compared with the passive TMD, the semi-active strategy provides a more controlled response and lower oscillation amplitudes after the initial transient, which may contribute to reducing structural loads and fatigue effects. These findings suggest that the use of NMPC in semi-active TMD systems represents a promising alternative for improving the dynamic stability of FOWTs.