A synthetic method for modelling transformer windings in the study of system switching transients

Switching operations cause high frequency oscillations in power supply networks. During thes oscillations, transformer windings are subject to voltage stresses. For the analysis of such transient phenomena, lumped networks consisting of R, L, C parameters calculated from the geometric dimensions of transformer windings have been used. In this paper, a new method is described for modelling of transformer windings by their terminal impedance characteristics. It is shown that, by the use of the given models the transient oscillations occuring on the transformer windings can be examined through the state equations. Examples are given for a reduced scale model transformer and an industrial supply system.