Optimal Adaptive Protection Using Setting Groups Allocation Based on Impedance Matrix

In this paper, an offline adaptive protection coordination based on Setting Groups (SGs) is proposed to consider the uncertainties in distribution networks. Distributed Generations (DGs) and line outages significantly change the patterns of fault current which results in miss-coordination and non-optimal tripping times. The SGs are systematically assigned based on the impedance matrix to cluster the different operating conditions of grid to a limited number of SGs, using kmeans method. Based on the assigned operating modes to each SG, an optimal coordination is solved to maximize protection system sensitivity, simultaneously preserving the selectivity in case of events like DGs disconnection and line outage. The proposed method is simulated on IEEE 30 Bus and optimum SGs are found using Genetic Algorithm (GA). The results indicate that relays present a robust protection while the selectivity is guaranteed.