@thesis{thesis,
		author={Erlina  Erlina and Isworo  Lakso and Lumban Gaol  Gita Ria},
		title ={ANALISIS SETTING RELE DIFFERENSIAL TRANSFORMATOR 60 MVA DI UNIT 2 GIS GROGOL 150 kV},
		year={2020},
		url={http://156.67.221.169/2830/},
		abstract={Power transformer in the substation is an important component in the electricity system because it is a component that connects the transmission subsystem with the distribution subsystem. For this reason, it needs to be maintained so that if there is interference with the transformer, damage can be limited. One important protection to protect transformers is differential protection. In this research, an analysis of the differential protection settings of 150/20 kV power transformer in GIS Grogol was conducted. Power transformer protection in GIS Grogol uses multifunctional numeric relay where differential is one of the protection functions. Settings are calculated based on manual relay, theory, transformer data, current transformer, and relay. This setting uses several calculation steps. Among them, the CT ratio of the 20kV side is 2000 / 5A, the CT ratio of the primary side is 300 / 5A. Slope K1 of 26% is assumed to be 30% by PLN standards. Is1 is 0.3 assuming the transformer resistance current is less than 10% or 0.1 taking into account tolerance, CT, and tap changer. Is2 is set at 2xIn where when the bias current is greater than In, the possibility of an error due to CT saturation becomes greater. And it is expected that with this adjustment the power transformer protection system can work optimally.}
		}