Mechanical characteristics of a new type of cable-supported photovoltaic module system

Abstract

Cable-supported photovoltaic (PV) modules have been proposed to replace traditional beam-supported PV modules. The new system uses suspension cables to bear the loads of the PV modules and therefore has the characteristics of a long span, light weight, strong load capacity, and adaptability to complex terrains. It provides an excellent supplement to traditional structures in special sites such as sewage treatment plants, highways, farms, fishponds, and roofs with poor load-bearing conditions. However, most of the traditional cable-supported PV systems use only two cables to support the PV modules. The settlement of the support cables due to self-weight of PV modules always reduces their power generation efficiency. Therefore, it is necessary to make a reasonable design to flatten the structures. Recently, the authors (He et al., 2020) proposed a new cable-supported PV system using three cables and four triangle brackets to form an inverted arch to reduce the vertical displacement of the PV modules. In this study, the structural characteristics of the new PV system with a span of 30 m are numerically investigated in terms of mode shapes, modal frequency, and nonlinear structural stiffness through using the finite element method. The increase of torsion stiffness when the torsion displacement rises benefits the stability of the new PV system. The load bearing capacity of the PV system is discussed under self-weight, static wind load, snow load, and their combination. The influences of row spacing, tilt angle, initial cable force, and cable diameter on the structural characteristics are further studied. The results verify that the new system has a strong load capacity and potential for wide application.