The Influence of Soil Two-Layer Structures on Substation Safety in Lightning Strike Conditions

Abstract Substation is one part of the electric power transmission system. In its distribution, it is inseparable from disturbances caused by lightning strikes. The disturbance occurs directly or indirectly so that a safety system is needed to prevent damage to equipment and personal safety. The safety system in question is the grounding system. A good grounding system will produce low soil resistivity. To obtain accurate soil resistivity values, soil type and grid configuration are very influential. This study discusses the rod grounding system with a square shape, touch voltage, step voltage on a two-layer soil structure. The grid configuration is equipped with varying conductor distances and conductor lengths. This study aims to determine the effect of the two-layer soil structure on the safety of the substation caused by lightning strike disturbances. The waveform simulation varies with a magnitude of 25 kA, 50 kA, 75 kA, and 100 kA.