Fully aeroelastic wind tunnel test method and determination of gust response factors in prestressed cable-supported photovoltaic array structures

Prestressed, cable-supported flexible photovoltaic (PV) arrays exhibit nonlinear aeroelastic behavior due to array interference effects, which are often oversimplified in engineering designs. This study investigates a three-span, five-row prestressed cable-supported PV array using a comprehensive aeroelastic model, which incorporates an equivalent stiffness PV section and a reduced-prestress wire rope. Additionally, a low-interference synchronous vibration and force measurement system was developed, combining an orthogonal arrangement of high-speed cameras and tensile sensors. Using the fully aeroelastic similarity model, this research systematically analyzes wind-induced self-excited vibrations in both single-span and multi-span PV arrays, while capturing the effects of array interference. The gust response factors of the cable-supported PV array were quantified, and three wind-resisting cable measures were proposed and experimentally evaluated. Results show that the fully aeroelastic model effectively captures both interference and aeroelastic effects. The measurement system enabled low interference, synchronous analysis of 3D aeroelastic responses. The cable-supported PV array maintained structural integrity across all row supports, with no critical wind velocity identified in any wind direction. The maximum recorded gust response factors were 1.371 for the single span, 1.381 at the midspan of the 3 x 5 array, and 1.376 at the side span of the 3 x 5 array. All three proposed wind-resisting measures successfully reduced vibration amplitude, achieving a maximum reduction of 6.63% in the gust response factor.