Optimization of Substation Grounding System Design on T-Shape Through Computer Simulation Approach

The grounding system is a safety system for electrical equipment failures, circuit disturbances caused by lightning strikes, and short circuit faults to the ground that can conduct to the human body. This study aims to optimize the design of the grounding system at substations with a T-shape grid and compare the cost efficiency required. The method used involves modifying the grid shape and adjusting the number of conductors on each axis of the T-shape grid design, as well as adding rod conductors. The touch voltage tolerance of the grounding system at the Substation of Electric Company in Pekanbaru is 737.6 V for a 50 kg body and 998.4 V for a 70 kg body, with a step voltage tolerance of 2458.2 V for a 50 kg body and 3327.1 V for a 70 kg body. The more economical design is the combination of the T-shape grid-rod with 8 conductors on the x-axis and 20 conductors on the y-axis, totaling 1345 meters in length, along with the addition of ground rods. The cost for this design is approximately IDR 315,587,250, which is lower than the design that only uses a grid with 10 conductors on the x-axis and 23 conductors on the y-axis, totaling 1,600 meters in length, costing IDR 373,200,000.