A Multi-Time Scale and Multi-Level Risk Assessment Method for Distribution Networks Considering the "Substation-Feeder-Transformer" Hierarchy

To address the increasing complexity of operational risks in distribution networks characterized by high renewable energy penetration, this paper proposes a multi-level risk assessment method targeting the "distribution transformer district-feeder-substation" hierarchy. Firstly, a multi-dimensional risk evaluation index system incorporating multiple time scales is constructed. Secondly, a combined weighting model fusing the entropy weight method and the Analytic Hierarchy Process is introduced to integrate subjective and objective information, thereby determining index weights scientifically. On this basis, a systematic multi-level risk assessment procedure and a quantitative calculation method are proposed. Finally, the effectiveness of the proposed method is verified through case study analysis. The results indicate that the method can accurately identify weak links at different levels, yielding more comprehensive and rational assessment results. It provides a quantitative basis for hierarchical precise prevention and control, as well as operation and maintenance decision-making for distribution networks.