Reliability evaluation algorithm for complex medium voltage electrical distribution networks based on the shortest path

This paper presents a reliability evaluation algorithm for medium voltage radial electrical distribution networks (EDN). The algorithm is suitable for evaluating reasonably complex EDNs with multiple subfeeders. It applies a forward-search-method to identifying the section controlled by a breaker. By applying graph theory and considering the structural features of the EDNs, methods for searching for the shortest paths from any node to the energy source and between any two nodes are developed. Based on the definitions of feeder terminal node (FTN) and the shortest path from a failure element to FTNs, it is easy to identify a disconnected section, following which a classification of the nodes is obtained. The reliability indices of the buses, feeders and system are calculated, based on the nodal classification. The developed algorithm has been tested on a number of test systems and the results show the effectiveness and applicability of the approach.