Dynamic Flexible Region Depicting Method for Active Distribution Networks Containing Massive Distributed Energy Resources

Driven by the target of “carbon peak” and “carbon neutrality”, the new energy industry has ushered in high-quality changes and development, and massive distributed energy resources such as wind and solar power generation and flexible load are connected to the distribution network, which challenges its secure and economic operation. Under this background, the introduction of region theory can visually perceive the secure flexibility range of distributed energy resources and provide a feasible space for the optimal scheduling of distribution networks. This study investigates how to depict the dynamic flexibility region of active distribution networks (ADNs), aiming to estimate and visualize distribution network flexibility. First, a flexible region model based on the DistFlow model is proposed, which takes the maximum/minimum power flexibility of the distribution network as the objective. Then, the dynamic flexibility region is estimated using the QuickFlex algorithm. Finally, the improved IEEE 33node distribution network is used for case analysis. The results show that this study accurately depicts the dynamic flexible region of ADNs and analyzes the properties and difference of flexible regions at different time periods, which makes the flexibility of distribution networks more intuitive.