Propagation of the voltage sags through different winding connections of the transformers

This paper analyzes the propagation of single phase voltage sag caused by line-to-ground short circuit in transmission network, from the high voltage level to the distribution level through various types of transformer. Two examples of the voltage sag propagation from transmission to the distribution level that are captured with the power quality measurements are presented. Measurement results and calculated results are corresponding to each other. This paper gives an example how the transformer winding connection influence on voltage sag propagation in real power system. Further work on this topic will include more types of voltage sags (not only single line) and more combinations of transformer windings connections. Also, the creation of the simulation model for voltage sags propagation will be the subject of the further work.