Graph Theory-based Distribution System Reliability Evaluation

Reliability evaluation helps distribution system planning and regulation by quantitatively assessing the power supply capacity under uncertainty. Its role is highlighted by the increasing frequency of extreme weather. This paper proposes a method of distribution system reliability evaluation based on graph theory. First, the reliability model of distribution system components such as lines, transformers, and loads are established. According to component reliability parameters, the sequential Monte Carlo simulation is used to randomly sample component states to generate the sequential state transition process of components, based on which the system states can be obtained. Then, combined with the distribution system graph model, the zone partitioning and minimal path search is applied to evaluate distribution system states. Finally, the reliability indices of distribution systems are calculated according to the system state evaluation results. The proposed method is applied to Roy Billinton Test System (RBTS) bus2 to verify its effectiveness and accuracy.