Analisis Koordinasi Rele Ocr (Over Current Relay) Dan Rele Gfr (Ground Fault Relay) Pada Feeder 20 Kv Pt Pln (Persero) Gardu Induk Pinrang

Abstract

The occurrence of failure of protective equipment when a short circuit occurs is caused, among others, by the lack of reliable and selective protection due to poor relay settings. This study aims to determine the magnitude of the short-circuit fault current in a 20 kV distribution network, to determine the coordination of the OCR-GFR relay working time with 20 kV input and to know how to simulate the coordination of the OCR-GFR relay working time based on the ETAP application. Collecting data using literature study, observation and interview methods, then data analysis is carried out using manual calculation methods and simulations using the ETAP application. The results for the study of 2-phase short-circuit faults at 36% of the length of the Kariango feeder (13.86 km) can be seen that, for manual calculations = 1500 A and for simulation results in the ETAP application = 1532 Ampere, then the relay that works in the case of the fault is OCR relay with a working/operating time of 1014 ms on the Kariango feeder side and a working/operating time of 4027 ms on the Incoming side of 20 kV. ETAP simulation results based on field data also show that the largest fault current is 3-phase short circuit at 0% feeder length, 5946 Ampere, Kariango feeder TMS = 0.19 (t = 489 ms), Incoming TMS 20 kV = 0.28 (t = 1045 ms) and the Grading Time value of the Kariango feeder with Incoming 20 kV is 556 ms (for the Grading Time value according to PT PLN standards, namely: a minimum of 0.3 seconds).