ANALISIS KEANDALAN SISTEM KOORDINASI PROTEKSI OVERCURRENT RELAY (OCR) DAN GROUND FAULT RELAY (GFR) DI GARDU INDUK 150 KV BUDURAN

RELIABILITY ANALYSIS OF PROTECTION COORDINATION SYSTEM OVECURRENT RELAY (OCR) AND GROUND FAULT RELAY (GFR) IN THE 150 KV BUDURAN SUBSTATION 

Sistem distribusi tenaga listrik adalah bagian dari sistem tenaga listrik yang berfungsi menyalurkan listrik kepada konsumen. Analisa keandalan sistem proteksi meliputi koordinasi antar peralatan proteksi dalam jaringan distribusi yang harus memenuhi standard. Penelitian ini bertujuan untuk menganalisa besaran nilai setting dan karakteristik overcurrent relay (OCR) dan ground fault relay (GFR) di Gardu Induk 150 kV Buduran menggunakan aplikasi ETAP 19.0.1. Metode penelitian yang digunakan adalah load flow analysis dan setting peralatan proteksi yang berdampak pada pengurangan risiko kerusakan pada peralatan listrik dan peningkatan keandalan sistem proteksi secara keseluruhan. Nilai setting OCR dan GFR ditentukan berdasarkan pada standard IEC 60255, relay yang terpasang pada GI 150 kV Buduran memiliki kurva karakteristik standard invers. Dari hasil penelitian diperoleh hasil bahwa besarnya arus gangguan hubung singkat dipengaruhi oleh jarak titik gangguan, semakin jauh lokasi gangguan maka arus gangguan hubung singkat akan semakin kecil, begitu pula sebaliknya. Ketika terjadi gangguan 3 fasa, maka relay penyulang Gedangan yang terlebih dahulu bekerja dengan setting selama 0,432 detik, dilanjutkan relay incoming dengan setting 0,61 detik sebagai backup proteksi, dengan setting arus 3401 A dengan jarak 11,5 km. Kata Kunci: distribusi tenaga listrik, relay, setting, ETAP.  

  Electrical distribution as a part of electrical power system has main function to feed electricity to cinsumers. Analysis of the reliability of the protection system includes coordination between the protection equipment in the distribution network with existing standard. This research focused on analyzing the setting value and characteristic of overcurrent relay (OCR) and ground fault relay (GFR) used in 150 kV Buduran substation using ETAP 19.0.1 software. The research method used is load flow analysis and setting of protective equipment, which impacts the reduction of risks of damage to electrical equipment and overall improvement of the reliability of the protection system. The value of current relay setting is referring to IEC 60255, because the relay is mounted on 150 kV Buduran substation with characteristic curve of standard invers. From the result of the study, it was found that the magnitude of the short-circuit fault current is influenced by the distance of the fault point, the farther the fault location is, the smaller the short-circuit fault current will bem and vice versa. When a 3-phase disturbance occurs, the Gedangan feeder relay operates first with a setting of 0.432 seconds, followed by the incoming relay with a setting of 0.61 seconds as a backup protection, with a current setting of 3401 A at a distance of 11.5 km. Keywords: electrical distribution system, relay, setting, ETAP.