Multi-objective coordinated optimization of flexible interconnected distribution networks under rainstorm conditions

The widespread integration of high-penetration distributed photovoltaic (PV) systems presents multiple challenges to distribution networks, particularly under extreme weather conditions such as short-term heavy rain, where issues like voltage violations and increased network losses become more severe. To address these challenges, this paper proposes a multi-objective coordinated optimization strategy for flexible interconnected distribution networks. The strategy establishes a multi-objective optimization model that comprehensively considers network losses, voltage deviations, PV output fluctuations, and regulation costs. It fully leverages the precise power flow regulation capability of the Soft Open Points (SOPs), coordinated with the fluctuation-smoothing effect of energy storage systems (ESS) and the voltage support function of multiple types of reactive power compensation devices. By introducing a special crowding distance (SCD) ordering mechanism, the traditional four-vector intelligent metaheuristic (FVIM) algorithm was upgraded to a multi-objective optimization algorithm for solution, significantly enhancing the quality of the Pareto optimal solution set. Simulation results based on the modified IEEE 33-bus and IEEE 39-bus systems show that the proposed strategy reduces the 24-hour total network loss by 19.17% and 6.37%, respectively, while keeping the minimum system voltage within the safe range throughout the day. Comparative analysis across multiple scenarios verifies the effectiveness and robustness of the strategy in smoothing PV fluctuations, optimizing system operation, and coping with extreme weather events. This research provides an efficient solution for the coordinated optimal operation of high-PV-penetration distribution networks, balancing economic efficiency, power quality, and operational stability.