Abstract
A lightning protection system (LPS) of an urban 110 kV substation is designed and analyzed according to NFPA 780 and IEC 62305-3 standards. The analysis of the LPS is established on the value of risk assessment. The total area of the substation has been described based on the modern designs represented by the real operational efficiency of the facility. This study aims to improve the understanding of the unexpected manner of the grounding system beneath lightning currents by clarifying the basic concepts of the lightning protection level. The mode was represented by the CDEGS software package, which provides effective geometrical modeling with object and result visualization. Furthermore, module and automated Fast Fourier Transform (FFT) is implemented in this study to simulate electromagnetic fields in the time and high-frequency domains. These current values are compared to the desired protection levels within the standards. The study results show that for the improved protection of the primary system against lightning, the total power grid must be considered as a source of improvement for studying shielding influence and the protection levels provided inside this substation. The lightning behavior of overhead transmission lines is associated with line flashover protection consequent to lightning strokes.