Graph Theory Based Heuristic Approach for Minimum Break Point Set Determination in Large Scale Power Systems

Coordination of directional relays in large-scale power systems that are multi-loop structured is a complicated and time consuming problem. Therefore, determination of the directional loops and the minimum break point set (MBPS) or a set close to it, which is essential to start relay coordination, is challenging. So far, several heuristics and exact methods have been proposed for the determination of the MBPS. In this paper, a new heuristic method based on a new implementation of depth-first search algorithm is proposed, which considerably facilitates the detection of directional loops (if any) in the network. The proposed method is tested on a 5-bus, four IEEE and four Polish test systems. The results show the efficiency of the proposed method in finding optimal or near-optimal solutions in a rational amount of time.