Evaluating the effect of initial pre-tension on wind-induced vibration in flexible cable-supported photovoltaic systems

In solar power technology, flexible cable-supported photovoltaic (PV) systems (FCSPSs) have become a viable alternative to conventional ground-mounted PV supports. These systems feature extended spans, a lightweight structure, and strong load-bearing capacity, making them notably resilient. Their flexibility is particularly beneficial in difficult environments such as mountainous areas, fish ponds, and sewage treatment facilities. Understanding the wind-induced vibration coefficient is crucial for accurately predicting how FCSPSs will respond to varying wind conditions. Due to the significant deformation caused by wind in FCSPSs, it's vital to perform a fluid-structure interaction (FSI) analysis to determine this coefficient. This study conducts a series of two-way FSI Computational Fluid Dynamics (CFD) simulations to examine how the initial pre tension force in steel cables affects the wind-induced vibration response of FCSPSs. First, modal analysis cases are performed with different initial tension forces in the steel cables. Next, the transient response of the cable-support structure and the changes in the wind field under load are assessed. Finally, the wind-induced vibration coefficient for both displacement and support reaction in the FCSPS is quantitatively evaluated. The results indicate that as initial pre-tension increases, the natural period and the reaction force's wind-induced vibration coefficient decrease, while the displacement wind-induced vibration coefficient rises. These findings offer valuable guidance for optimizing pre-tension to reduce wind-induced vibrations, thereby improving the stability and efficiency of FCSPSs.