Analysis of indirect lightning phenomena on solar power system

Abstract

A threat of solar power systems is lightning induced voltage, which can damage the photovoltaic generators and its ancillary equipment, has been examined in this paper. The induced voltage due to lightning strike can be reduced using a lightning protection system; however there is a possibility of getting damage of system equipment from electromagnetic interference. The induced voltage on the Power Condition System (PCS) of solar power system is analyzed using electromagnetic analysis approach. The effects of strike height and soil resistivity have been considered for analyzing the induced voltage on a system. We examine, with the increasing strike height and rising soil resistivity how the induced voltages of a system are affected. We found that with the increasing strike height the induced voltage also increases except the line to ground voltage, and with the rising soil resistivity induced voltages are approximately constant excluding frame voltage. Virtual Surge Test Lab (VSTL), which utilized the finite-difference time-domain (FDTD) method for solving Maxwell's electromagnetic equations, was used to compute the induced voltages. The solar power system was modeled with thin wire structures having good representational capacity of a steel frame and power line to induced voltage.