Sistema de proteção contra descargas atmosféricas em campo aberto para usina fotovoltaica: um estudo de caso

Abstract

This work presents the development and analysis of a Lightning Protection System (LPS) applied to a 1.4 MWp photovoltaic plant located in the municipality of Naque, Minas Gerais. The study aimed to evaluate the risks associated with lightning strikes in solar power generation installations and to propose an appropriate protection system, according to the criteria established by ABNT NBR 5419:2015. Initially, a risk analysis of the installation was carried out, considering parameters such as the density of lightning strikes in the region, the constructive characteristics of the plant, and the exposure of the equipment. Based on the results obtained, a Class IV LPS was defined, using the rolling sphere method for the dimensioning of the capture system. The project resulted in the installation of 43 capture masts with a height of 4.3 m, distributed throughout the plant area, interconnected by a 70 mm² galvanized steel grounding grid. Additionally, a soil resistivity test was performed using the Wenner method to characterize the grounding conditions of the area. After the system was implemented, an atmospheric event was recorded near the plant, evidenced by the activation of the surge protection devices, without any damage to the plant's equipment. The results indicate that the implemented protection system performed satisfactorily, contributing to the protection of the plant's assets and the operational reliability of the project.