Assessment of Distribution Network Security Carrying Capacity under Emergency Incidents

With the widespread application of distributed power sources and energy storage devices, distribution networks exhibit more unknown characteristics. Emergency incidents in the power system pose a significant threat to the stable and secure operation of the grid. In order to analyze the security carrying capacity of distribution networks, we first construct node influence indicators based on M-order neighbor quantity and entropy theory. Subsequently, considering the impact of emergency incidents on the distribution of power flows, a security carrying capacity evaluation method that considers power flow distribution balance in the grid is proposed. Additionally, a strategy for selecting critical safety constraints based on an iterative method is introduced, enhancing solution efficiency by focusing solely on crucial safety constraints in the optimization model to satisfy all feasible power flows. Finally, the evaluation model is applied to analyze the IEEE 33-node test system, validating the proposed approach for analyzing the security carrying capacity of distribution networks under emergency incidents while ensuring economic viability and aligning with current development needs in distribution networks.