Planned or forced outage of parallel and series photovoltaic (PV) units may disrupt the coordination of overcurrent relays and violates the optimization constraint. In this paper, a new hybrid method is proposed for setting group (SG) based coordination of overcurrent relays. The proposed technique exploits K-means and interval linear programming (ILP) and takes the PV systems’ uncertainty into account. In the recommended hybrid algorithm, the clustering method k-means is firstly use to classify variable size and outage of PVs into several clusters so that their number would be equal to the number of SGs in the relay. Due to fault current changes in each cluster, ILP is then applied to solve overcurrent relay coordination problem. The proposed technique\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\'s performance has been tested on the IEEE 8- bus distribution system with two PVs. The results show that in the proposed method, the coordination of relays is maintained, and their operating time is optimized.

Keywords