Ground Fault Protection Using Open Break Delta Grounding Transformer in Ungrounded System

One of the most common and difficult problems to solve in distribution power systems is the location and elimination of the ground fault. This paper presents a method for ground fault protection system scheme is used overvoltage relays and open break delta transformers, whereas for fault location detection using voltage transformers in star connections. An experimental for further understanding about the electrical distribution network, the ungrounded system will be operated at 20 kV on the primary and 380 V on the secondary. The model uses smaller nominal voltages consisting of 380 V on the primary and the secondary. The highest single line to ground fault value is used for consideration of ballast rating selection. The single line to lowest ground fault value is used for setting the threshold on the voltage relay (59N). The result of one phase fault protection mechanism works well at each point of interference, and voltage transformers are protected from overheating and damage. The lowest value of the single-phase to ground short circuit that occurs at the fault location at the farthest point of interference from the protection relay location is used for the threshold setting on the voltage relay. The one phase fault protection mechanism works well at each point of interference, and the voltage transformer is protected from overheating and damage..