Algorithm for the Analysis of Coordination of Protection for Distribution Systems

The selectivity and coordination of overcurrent relays is most commonly studied distribution systems protection. This paper proposes a method for detailed analysis of the overcurrent protection of distribution systems, in which the phase unbalances, neutral conductor and groundings are to be taken into account. All calculations are performed in a full three-phase methodology. The mathematical models of the main protective equipment and protective functions found in distribution systems were also developed. Two distribution systems were analyzed to verify the efficiency of the proposed methodology.