Floating offshore wind turbine vibration control based on Tuned Liquid Multi-Column Damper

In this study, a 16-degree-of-freedom rigid-flexible coupled floating offshore wind turbine (FOWT) model is con structed based on the International Energy Agency (IEA) UMine 15-MW semi-submersible wind turbine. Similarly, a Tuned Liquid Multi-Column Damper (TLMCD) system model was developed and integrated into the FOWT-TLMCD model for vibration control of flexible tower and platform motions. The accuracy of the FOWT model was verified by comparing the dynamic response of the FOWT model with the simulation results from OpenFAST. Subsequently, a linear quadratic regulator (LQR) control algorithm was used to regulate the damping force of the TLMCD valve. Comprehensive numerical simulations were performed under various wind and wave conditions. The results show that the standard deviation of the platform pitching motion as well as the standard deviation of the tower top fore-and-aft displacement are significantly reduced with the TLMCD control system. In addition, the integration of the LQR control further enhances the suppression effect on platform pitch and tower top displacement, and this control effect becomes more and more obvious under windy conditions.