%0 Journal Article
	%A M. N. Moschakis and  V. V. Dafopoulos and  I. G. Andritsos and  E. S. Karapidakis and  J. M. Prousalidis
	%D 2013
	%J International Journal of Electrical and Computer Engineering
	%B World Academy of Science, Engineering and Technology
	%I International Science Index 79, 2013
	%T The Effect of Transformer’s Vector Group on Retained Voltage Magnitude and Sag Frequency at Industrial Sites Due to Faults
	%U https://publications.waset.org/pdf/16272
	%V 79
	%X This paper deals with the effect of a power transformer’s vector group on the basic voltage sag characteristics during unbalanced faults at a meshed or radial power network. Specifically, the propagation of voltage sags through a power transformer is studied with advanced short-circuit analysis. A smart method to incorporate this effect on analytical mathematical expressions is proposed. Based on this methodology, the positive effect of transformers of certain vector groups on the mitigation of the expected number of voltage sags per year (sag frequency) at the terminals of critical industrial customers can be estimated.

	%P 835 - 841