Considerations of Photovoltaic System Structure Design for Effective Lightning Protection

Photovoltaic (PV) systems are susceptible to lightning strikes. During a lightning strike, an induced overvoltage is generated in the PV system. This overvoltage can damage the inverters connected to the dc cables. In this article, a comprehensive study is presented to address the installation issues that will influence the induced voltage between the +dc and -dc cables in the PV system. By using the partial element equivalent circuit method, the skin effect and ferromagnetic property of the mounting structures are well modeled. The wiring in the PV module is also considered in the simulation. The influences of the mounting systems, lightning protection systems, PV frames, and dc cable arrangements are thoroughly investigated. The simulation results and discussions provide guidance for PV structure design for maximizing lightning protection performance without adding additional protective devices.