Analisis Gangguan Drop Tegangan Akibat Beban Penuh Pada Penyulang Inggris Jurusan Sudirman menggunakan Software Etap Di PT. PLN (Persero) UP3 Dumai

Voltage quality is a critical parameter in 20 kV distribution systems, requiring voltage drop to remain within the established tolerance limits. This study analyzes the voltage drop caused by full-load conditions on the Inggris Feeder, Sudirman Section, at PT PLN (Persero) UP3 Dumai, ULP Dumai Kota, using ETAP 12.6 software. The research method includes collecting network technical data, modeling a Single Line Diagram (SLD), performing manual calculations, and conducting load flow simulations, the results of which were then compared and analyzed. The SLD was modeled according to actual network conditions, consisting of 44 buses, 24 AAAC 150 mm² cable segments, and 18 distribution transformer units. Manual calculations yielded a voltage drop of 0.49% with power losses of 4.04 kW (0.35%), while the ETAP simulation showed voltage drops per substation ranging from 0.73% to 2.89% (average 1.72%) with total system power losses of 14 kW (1.98%). Both methods consistently showed voltage drops well below the SPLN maximum limit of 5%, with no substations experiencing overload conditions. The largest voltage drop was identified at substation DMI134 (Bus47), at 2.89%. In addition, load imbalance analysis revealed a fairly wide variation among substations, ranging from 2.99% to 80.00%, which warrants attention despite the Inggris Feeder network generally operating well overall.