DESAIN SISTEM PROTEKSI ARUS LEBIH DAN DIFERENSIAL PADA SAT (STARTUP AUXILLARY TRANSFORMER) DI PLTU 2 JAWA TENGAH ADIPALA

RONI DWI PRASETYO, Sarjiya, S.T., M.T., Ph.D., Lesnanto Multa Putranto, S.T., M.Eng., Ph.D.

2019 | Skripsi | S1 TEKNIK ELEKTRO

Penelitian ini bertujuan untuk mendesain sistem proteksi Startup Auxillary Transformer (SAT) dari gangguan internal dan eksternal dalam 3 skenario operasi. Desain sistem proteksi tersebut mencakup penetapan rating Current Transformer (CT), rating Circuit Breaker (CB), setting rele arus lebih dan setting rele diferensial. Tools Digsilent PowerFactory 18.1 yang digunakan untuk menentukan rating CB dan CT adalah Load Flow dan Short CIrcuit Analysis, sedangkan untuk menentukan setting rele arus lebih SAT dan setting rele diferensial SAT digunakan tools Protection and Arc Flash Analysis. Hasil yang diperoleh berupa rating CT sesuai standar IEC 60044, rating CB sesuai standar IEC 60694, koordinasi rele arus lebih dan koordinasi rele diferensial. Berdasarkan hasil simulasi, setting rele arus lebih SAT sudah mampu berkoordinasi dengan sistem proteksi eksisting dan mampu menjadi backup bagi rele diferensial SAT. Disamping itu, setting rele diferensial SAT sudah terkoordinasi karena hanya beroperasi ketika terjadi gangguan di dalam zona proteksi diferensial dan tidak beroperasi ketika gangguan terjadi di luar zona proteksi diferensial.

This study aims to design a Startup Auxillary Transformer (SAT) protection system from internal and external faults in 3 operating scenarios. The design of the protection system includes determining the Current Transformer (CT) rating, Circuit Breaker (CB) rating, overcurrent relay settings and differential relay settings. Digsilent PowerFactory 18.1 tools used to determine CB and CT ratings are Load Flow and Short CIrcuit Analysis, while to determine SAT overcurrent relay settings and SAT differential relay settings are used tools Protection and Arc Flash Analysis. The results obtained are in the form of rating CT according to IEC 60044 standard, CB rating according to IEC 60694 standard, coordination of overcurrent relay and differential relay coordination. Based on the simulation results, the SAT Overcurrent Relay setting has been able to coordinate with the existing protection system and is able to become a backup for SAT differential relay. Besides that, the SAT differential relay setting has been coordinated because it only operates when there is fault within the differential protection zone and does not operate when fault occurs outside the differential protection zone.

Kata Kunci : Rating CT, rating CB, setting rele arus lebih SAT, setting rele diferensial SAT dan berkoordinasi/rating CT, rating CB, SAT Overcurrent relay setting, SAT differential relay setting, and coordination