Analysis of Compensator Requirements in the Grid System with Variation Load

Abstract

Reactive power management and voltage control are critical challenges in modern power systems,
particularly in extra high voltage (EHV) networks operating under low loading conditions. This study analyzes
the requirement and placement of reactive power compensators in the 275 kV Sulbagsel transmission system based
on the RUPTL 2025–2034 planning scenario using DIgSILENT PowerFactory.
The system exhibits low transmission line loading, resulting in dominant capacitive effects due to line charging,
which leads to overvoltage conditions. Power flow simulations under various load scenarios from 2023 to 2030
indicate that line loading remains below 10%, causing excessive reactive power in the system.
To maintain voltage within the permissible grid code limits, additional reactive power compensation is required.
The results show that a total of 200 MVAr shunt reactor is needed, optimally installed at Bungku and Kendari
substations, each with a capacity of 100 MVAr.
This study contributes to long-term reactive power planning in lightly loaded EHV systems and provides practical
insights for transmission system development under high uncertainty of industrial load growth.