Vibration control of floating offshore wind turbine using semi-active liquid column gas damper

Floating offshore wind turbines (FOWTs) are becoming an essential instrument for energy generation worldwide. Specific environmental conditions at sea have led to unwanted vibrations and excessive displacement in floating wind turbines, which reduce the performance of these systems. This study aimed to evaluate the effect of semi active liquid column gas damper (SALCGD) on controlling the vibrations of a FOWT under different loads with wave and wind. Variable hydraulic head loss coefficient and variable frequency were used in this study, as well as DBG, VBG, and Bang-Bang algorithms. An analytical model was developed to analyze the dynamic response of the joint wind turbine and damper system, and a time history analysis was performed in the SIMULINK/MATLAB simulation environment. The results indicated that the SALCGD could reduce the displacement response of the pitch degree of freedom in platform in both semi-activation methods. In addition, the performance of each control algorithm varied according to the loading conditions. The effect of SALCGD and TLCGD (tuned liquid column gas damper) was compared in controlling the vibrations of the wind turbine system. According to the results, the superiority of using a semi-active damper was revealed in control.