Optimal Combination of Protection Systems and Defense Scheme for A Radial Transmission of Timor Power System

The Timor Power System is the largest electrical power network within the operational area of PT PLN (Persero) UIW NTT, supplying electricity to the majority of customers in the region. In 2023, it recorded a peak load of 123.74 MW, increasing to 127.45 MW in 2024. Historical disturbance data from 2020 to 2024 indicate 63 recorded transmission line faults, with lightning strikes identified as the dominant cause - accounting for 57 events or approximately 90.4 of total incidents. Due to its radial configuration, any disturbance along the backbone transmission line often triggers wide-area outages and, in severe cases, full system blackouts. This study investigates, simulates, and compares various protection and defense scheme configurations specifically designed for small and radial power systems such as the Timor System. The scenarios include adaptive protection settings, optimal coordination of auto-reclosing and load shedding, and defense strategies to enhance operational resilience. The results provide technical recommendations to improve reliability, minimize outage impacts, and strengthen overall system stability.