The transmission network is a high-voltage electrical infrastructure that functions to deliver electrical energy from power plants to substations and subsequently to customer substations, with the objective of ensuring efficient power distribution and minimizing energy losses. A voltage drop issue occurred at the Bantaeng Switching Substation owned by PLN, which supplies electricity to the Smelter Substation of PT Huadi Nickel Alloy, a premium customer that requires a large amount of power for nickel smelting and other industrial operations. Measurement results showed that the voltage at the Bantaeng Switching Substation, initially at 150 kV, dropped to 140.1 kV on two circuits connecting Bantaeng Switching to the Smelter Substation. According to the SPLN standard, the system voltage must remain within a tolerance range of +5% to -10% of the nominal voltage, or between 135 kV and 165 kV. To address this issue, the Bantaeng Switching Substation installed shunt capacitors with capacities of 25 MVAR and 50 MVAR, which successfully increased the voltage to 144.6 kV. The use of capacitors was chosen not only because they are effective in improving the power factor but also due to their easier maintenance and lower investment costs compared to other compensation methods