Simulation of Voltage Sag Events in Distribution Networks and Utility-Side Mitigation Methods

As the industrialization and automation processes continues to grow and expand, power quality parameters and especially voltage sags gain more importance. Limits defined by regulatory authorities are getting stricter and distribution companies applies several methods to avoid penalties and meet the customer needs. Trakya Electricity Distribution Company (TREDAS) has initiated an R&D project to characterize and mitigate the voltage sags and this study shares a part of project results. In this paper, definitions of voltage sag indices are given and methods used to minimize effects of voltage sags are explained and summarized. A feeder located in Thrace region was modeled in EMTP-RV software and examined the effects of faults on voltage sags. Also, utility-side mitigation methods are modeled in software as well and results are analyzed.