This paper investigates post-disaster restoration and stable operation of three-phase unbalanced distribution networks with high penetration of distributed generation and electric-vehicle integration. A two-stage hierarchical restoration and coordinated dispatch strategy is developed to improve restoration feasibility and reliability while reducing post-fault restoration cost. In Stage I, island partitioning and load prioritization are carried out using DFS and BFS to maximize the restoration of critical loads. In Stage II, without reducing the Stage I restoration level, branch switch statuses and coordinated outputs of DG-EV-BESS are jointly optimized under three-phase unbalanced power flow, radiality, and other operational constraints. The objective minimizes the total restoration cost, including network losses, switching operations, three-phase voltage-unbalance penalties, and customer compensation. Simulation results on a modified IEEE 33-bus system demonstrate that the proposed method reduces restoration cost and improves the system restoration ratio. In addition, phase-wise EV dispatch provides targeted compensation for weak-phase power deficits and improves post-fault inter-phase operating quality. The results validate the effectiveness of the proposed strategy.
Sun et al. (Mon,) studied this question.