Evolution of wind-induced vibration form of large-span flexible PV aeroelastic arrays

•Synchronous full-array aeroelastic wind tunnel tests of vibration and force are conducted using the high-speed photography technology.•The characteristics of wind-induced vibration response and the evolution of wind-induced vibration form are analyzed. Research on wind-induced vibration of large-span flexible photovoltaic(PV) array only give wind-induced response analysis and vibration reduction measures, but ignore morphological evolution laws among arrays. In this study, an aeroelastic model of 3-span 5-row suspension cable flexible PV array was designed with considerations to similarity ratio relationship of a strict wind tunnel test. Synchronous full-array aeroelastic wind tunnel tests of vibration under different wind direction angles and wind speed were carried out. The responsible characteristics of the structural system were analyzed systematically by using variation modal decomposition. Results demonstrated that strong vibrations were observed in the single row of PV when the wind speed was above a critical value. The support designed between PV array can restrain the strong wind-induced vibration. The wind-induced vibration degrees of each row of PV array are different, but the laws are basically consistent. The first row in the direction of the incoming flow vibrates at a low frequency. The wind-induced vibration of PV panel is mainly random buffeting, the farther away from the wind field, the more obvious the torsion. The vibration energy of vertical displacement of the PV array changes from low-order mode to high-order mode with the increase of row number. The energy dissipation phenomena of high-frequency intervals at the fifth downwind row are more obvious.