Improvement of Transmission Line Grounding System using Conductive Cement

Lightning is a natural phenomenon that cannot be avoided, lightning can strike anywhere and anytime depending on the situation and environmental conditions. Lightning has been the biggest caused of transmission faults in most PLN transmission units over the past few years. Transmission line is easy to be struck by lightning, because of its high position and being in an open space. If transmission line grounding system functions properly, the over voltage caused by lightning strikes can be earthing to the ground easily, without causing traveling wave. However, if earthing cannot distribute badly, it can cause transmission fault. Improving transmission line grounding system besides using a good grounding connection from top to bottom grounding, we need to check also properly to ensure a good bottom grounding resistance value, especially in soils with high resistance such as rocky areas. Conductive cement is one of the solutions to improve the transmission line grounding system by replacing the surrounding soil with a low resistance cement. In its implementation, conductive cement can use with ground rod or ground plate and must be well calculated. For ground rod, the influencing factors are diameter of ground rod, diameter of hole, number of rods and spacing between rods. As for the ground plate is plate depth, plate diameter and plate dimensions. Monitoring the implementation of conductive cement that has been implemented using the parameters above shows good results, where using conductive cement with a ground rod can reduce the value of grounding resistance by up to 93% and using a ground plate can decrease by up to 85%. From routine monitoring every month, the value of the grounding resistance is stable until the 9
^th
month, which has passed the rainy and dry season, so that it can be concluded that conductive cement is effective to improving the transmission line grounding system.