A Rapid Risk Assessment Method for AC-DC Distribution Networks with Source-Load Uncertainty

Traditional AC distribution networks have limited regulation and control methods and insufficient operational flexibility and are prone to the problems of over-voltage when a high proportion of renewable energy is connected. AC-DC hybrid distribution network (HDN) can realize flexible power transfer in space and time through converters and energy storage devices to achieve complementary interconnection between networks, thus making full use of the resource endowment in different regions, improving the efficiency of power utilization. Traditional risk assessment methods mainly focus on AC distribution networks. However, the abundant quantity and intricate nature of uncertain factors in high dimensional networks, coupled with their variable operational modes, render risk evaluation increasingly challenging. In this paper, our proposal entails a rapid risk assessment approach for HDNs encountering source-load uncertainty, with the objective of expediting risk evaluation and offering operational and dispatch guidance. A Gaussian mixture model is employed to depict the source-load uncertainty and conduct probabilistic power flow analysis. By integrating the risk-utility function, the operational risk of the system can be appraised. Ultimately, a case study is conducted to substantiate the efficacy of our proposed methodology.