Impact of distributed generation on network security: Effects on loss-of-main protection reliability

Abstract

The growing penetration of GD in distribution networks determines a complete redeployment of power flows along distribution feeders, thus causing altered voltage profiles and new issues in protection reliability. This paper addresses the issue of island opening operation, by using detailed models of GD sources and analyzing the frequency and voltage oscillations induced by islanding in different condition of power flow on the interrupted branch. The aim is to identify which network conditions should be considered as possible causes of loss-of-main protection bad operation.