A Multi-Stage Collaborative Optimization Operation Method for Distribution-Microgrid for Reliability Improvement

In recent years, micro grids have played an increasingly important role in the construction of new type power systems This also renders distribution networks (DN), characterized by comparatively weaker structural resilience, increasingly susceptible to extensive and prolonged outages in the event of faults. This paper proposes a multi-stage coordinated optimization method for distribution-microgrid systems based on flexible soft-switching. In the pre-disaster phase, a preventive model is developed to deploy mobile energy storage and adjust operating modes. During the disaster phase, measures such as switch isolation and mobile energy storage power regulation are implemented. In the post-disaster phase, a scheduling model for mobile energy storage and construction teams is integrated to form a multi-stage coordinated optimization model. The model is then formulated as a bilevel mixed-integer linear programming problem and solved iteratively using the Column and Constraint Generation (C&CG) algorithm to achieve optimal resource allocation. Case studies demonstrate that the SOP-based multi-stage distribution-microgrid cooperative optimization strategy significantly improves power supply continuity for loads during faults, reduces restoration times, and enhances overall grid reliability.