Technical gazette, Vol. 17 No. 1, 2010.
Original scientific paper
Analyzing of relevant fault type for calculation of minimum fault current magnitude on distribution transformer primary side
Vedran Boras
; University of Split, Faculty of Natural Sciences and Mathematics, Department for Polytechnic, Teslina 12, 21000 Split, Croatia
Tomislav Barić
; University of Osijek, Faculty of Electrical Engineering, Kneza Trpimira 2b, 31000 Osijek, Croatia
Alija Muharemović
; University of Sarajevo, Faculty of Electrical Engineering, Zmaja od Bosne bb, 71000 Sarajevo, Bosnia and Herzegovina
Abstract
The paper analyses the influence of three-phase transformer connections and several types of bolted shunt faults (short circuits), which occur on a distribution transformer secondary side as well as simultaneous faults in determining of relevant fault type for calculation of minimum fault current magnitude on the transformer primary side, which will be relevant for the selection of fuse-links minimum breaking current of high-voltage fuses for transformer circuit applications. The two transformer connections: delta primary-grounded star secondary (denoted as Dyn) and star primary-grounded interconnected star secondary, also known as zig-zag (denoted as Yzn) are enclosed in the carried out analysis. In this paper a simultaneous fault involves the shunt fault on the transformer secondary side with blown fuse in any phase on the transformer primary side. Calculation of these faults is carried out by means of the symmetrical components method in per-unit.
Keywords
fuse-links minimum breaking current; high-voltage fuses; shunt fault; simultaneous fault; three-phase transformer connection
Hrčak ID:
50598
URI
Publication date:
31.3.2010.
Visits: 9.492 *