This study aims to improve the reliability of a 20 kV distribution network by optimizing protection coordination for the Jampue and Kariango feeders in the Pinrang region, Indonesia. The primary challenges include protection miscoordination caused by suboptimal overcurrent and ground fault relay settings, which result in delayed fault isolation and unnecessary outages. Using ETAP software, a detailed simulation model of the network is developed to analyze various fault scenarios and evaluate the performance of the existing protection system. The results reveal significant instances of miscoordination, particularly during low-magnitude faults, and highlight the limitations of current relay settings. To address these issues, optimized relay settings are proposed through a data-driven approach that considers coordination time intervals, minimum pickup current, and maximum tripping time for each relay. These optimizations enhance selective tripping and reduce fault-clearing times. The impact of the proposed improvements is quantified through reliability indices, showing reductions of 25% in the System Average Interruption Duration Index (SAIDI) and 15% in the System Average Interruption Frequency Index (SAIFI). This research introduces a novel hybrid approach that combines traditional relay coordination methods with simulation-based optimization, providing a practical framework for improving the reliability of distribution networks, particularly in areas with diverse load profiles and DER penetration.
A Sat, study studied this question.