The Effects of Sulfuric Acid and Salt on the Resistance Value of Bentonite Grounding in the Limestone Soil

The grounding system is critical for maintaining the electric power system's safety and reliability. However, obtaining an appropriate grounding resistance value in limestone soils is challenging. According to prior research that has employed bentonite as a grounding medium, the reduction in resistance caused by bentonite is not very effective. In addition, research has shown that adding sulfuric acid (H2 SO4) to bentonite reduces the value of grounding resistance. Grounding resistance is also reduced when salt (NaC1) is combined with bentonite. This study investigated the effects of adding sulfuric acid (H2 SO4) and salt (NaC1) to bentonite at different concentrations to help reduce the grounding resistance value of limestone soil using the same addition method. In this study, the effect of sulfuric acid and salt on bentonite grounding has been discussed. Several combinations of sulfuric acid and salt compositions for grounding bentonite have also been carried out. Each composition is implemented on lime soil. After that, the grounding resistance was measured. This value is entered into the grounding replacement circuit. This is done to observe the potential ground rise due to lightning strikes. Lightning characteristics used are 10 kA with a waveform of 8/20 μs. In addition, a finite-element method (FEM) simulation was also carried out to describe the potential distribution for each condition. Based on the simulation results, it is known that the potential ground rise in limestone soil is 3.24 MV. While the smallest potential ground rise is the composition of bentonite and 0. SM salt, which is 0. S6S MV.