Cable-supported photovoltaic systems (CSPSs) have been widely adopted as a solar energy solution due to their low consumption of steel, large spans, and strong terrain adaptability. However, their susceptibility to wind-induced vibrations, such as flutter and buffeting, could lead to structural failure. These wind-induced responses are greatly affected by the dynamic characteristics of CSPSs, i.e., modal frequencies, mode shapes, and damping ratios; however, their theoretical modeling and evolution rules remain underexplored. Using Hamilton’s principle, this study derives practical formulas for bending, torsional, and lateral modal frequencies of a single-layer CSPS accounting for cable tension, cable spacing, span, photovoltaic (PV) module mass, PV module stiffness, and tilt angle of PV modules. The formulas are validated through finite element analysis, field tests, and aeroelastic model tests, demonstrating satisfactory accuracy within common parameter ranges. The assumptions of critical factors in modeling are clarified. The results reveal that bending and torsional frequencies initially decrease and then increase with cable tension, whereas both decrease with PV tilt angle. Torsional frequency increases with cable spacing. The cable spacing-to-section length ratio ( 𝑑 / 𝐵 ) is the key factor determining the torsional-to-bending frequency ratio, estimated as 1 . 7 3 𝑑 / 𝐵 . The stiffness of the solar plate has negligible impact on torsional frequency, whereas the aluminum frame contributes slightly more. Still air reduces both bending and torsional frequencies, with bending frequency decreasing by up to 7.3%. The sag increases the bending and torsional frequencies of symmetric modes but does not affect asymmetric modes. Flutter stability is enhanced by limiting cable spacing, which helps maintain a moderately low frequency ratio, increasing flutter speed, or even eliminating flutter. A relatively low tilt angle helps mitigate buffeting and reduce wind loads. The theoretical modeling and resulting formulas provide important information for optimizing wind-resistant design of CSPSs, contributing to their safer and more reliable implementation.
Fang et al. (Sat,) studied this question.