Experimental study of structural vibration control of 10-MW jacket offshore wind turbines using tuned mass damper under wind and wave loads

Abstract

As slender structures, offshore wind turbines (OWTs) are prone to vibration and deformation under wind and waves. Tuned mass dampers (TMDs) have become among the most promising vibration-mitigation methods owing to their simplicity and practicability. To study the vibration control effect of a TMD on a jacket OWT under wind and wave conditions, we conducted a fully coupled dynamic model test of a 1/75 scale jacket OWT with and without a TMD. The physical model of the jacket OWT included scaled rotor-nacelle assembly (RNA) and support structure models. For the scaled RNA model, a redesigned blade model was used to ensure similarity of the aerodynamic thrust loads without modifying the scaled test winds. Drivetrain and pitch-control system models were designed to simulate the operating state of an actual OWT. The support structure model was established based on the hydro-structural elastic similarity. Furthermore, a TMD model was designed and manufactured based on the first mode of the scaled OWT. A fully coupled dynamic model test of a 10 MW jacket OWT with a TMD under wind and wave conditions was performed, and the vibration-mitigation performance of the designed TMD model on the structural responses of the scaled OWT model was evaluated.