Generalized distance-based protection design for DG integrated MV radial distribution networks — Part II: Application to an actual distribution line

Abstract

The first part of this two-paper series proposes generalized guidelines for the design of distance protection in medium-voltage radial distribution systems with distributed generation. In this second part, these guidelines are applied to a real medium-voltage radial overhead distribution line of the area of Xanthi, Greece. A considerable penetration level of distributed generation is also assumed for this application. Based on the proposed guidelines, the designed protection scheme addresses all the factors affecting distance relay operation in distribution system applications, also dealing with any particularities of the specific distribution system examined. The installed distance relays prove to operate dependably and selectively against various faults, considering different fault types, fault positions, fault resistance and penetration level of distributed generation. In fact, selectivity is preserved between the distance relays and the remaining protection means (fuses) in the line, as well as between successive distance relays. Economic feasibility of the designed distance protection scheme is evidently taken into account, as the minimum number of distance relays is ultimately installed.