High penetration of distributed generators introduces severe spatiotemporal source-load imbalances in distribution networks

thereby intensifying risks at critical nodes and undermining defensive capabilities through the power tidal effect. Although energy storage system-integrated soft open point (E-SOP) can effectively compensate for spatiotemporal power deficits

existing researches constrained by cost concerns and computational complexity often employ idealized E-SOP models

which ignore voltage and current fluctuations in expanded DC-links

and lack dynamic node security margins

leading to distorted resilience assessments and local optima. This paper proposes a bi-level collaborative regulation- operation optimization method for E-SOP security concerning DC-link calculation: This paper develops a refined E-SOP model embedding dynamic DC-link characteristics to quantify internal power equilibrium

and establishes a model concerning device-node security with multi-dimensional margins to track power impacts on operational boundaries. Based on the proposed bi-level collaborative optimization framework

this paper employs differential evolution algorithm to optimize E-SOP site selection and dispatch strategy. In the modified IEEE 123-node system

the effectiveness is verified among device safety

grid resilience and low-carbon economy

providing an innovative solution for the distribution network with flexible interconnection.