Numerical study of using shape memory alloy-based tuned mass dampers to control seismic responses of wind turbine tower.

• SMA-based TMDs were proposed and optimized to control the seismic responses of wind turbine tower. • Effectiveness of SMA-based TMDs in the seismic response mitigation of wind turbine tower was investigated. • Control performances of SMA-based and linear TMDs were compared. This study proposes replacing the spring and dashpot elements in the conventional tuned mass damper (TMD) by shape memory alloy (SMA) wires to form an SMA-based TMD to control the seismic responses of wind turbine tower. An equivalent linearization method is adopted to optimize the initial stiffness of SMA-based TMD by minimizing the root mean square (RMS) displacement of the tower. To have an insight into the control performance of SMA-based TMDs, a three-dimensional (3D) finite element model of a typical wind turbine tower is developed in ABAQUS, and tower responses without and with SMA-based TMDs when subjected to simulated and recorded ground motions are systematically analysed. For comparison, seismic responses of the tower controlled by the linear TMDs are also simulated. Numerical results show that the SMA-based TMDs can substantially mitigate seismic responses of the tower with almost the same reduction ratios as the linear TMDs, while the strokes of the SMA-based TMDs are much smaller than those of the linear TMDs. This merit makes the proposed method more practical compared to the conventional TMD-based method since the space in the nacelle and tower is normally very limited. [ABSTRACT FROM AUTHOR]