Effects of autotransformer’s stabilizing winding on current-voltage conditions during unsymmetrical faults

In this paper, model of three-phase autotransformer with stabilizing winding is developed in EMTP for shortcircuit studies. Currents and voltages are determined inside transformer windings during unsymmetrical faults in the power system. Influence of delta connected stabilizing winding on current- voltage conditions is analysed. Results obtained by EMTP model are compared with the inductance matrix model of autotransformer developed in Matlab, consisting of winding self-inductances and corresponding mutual inductances between windings.