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电力系统恢复后期的网架重构和负荷恢复是一个复杂的多步混整非线性规划问题。为了降低其求解难度和提高求解效率，提出一种适用于网架重构和负荷恢复的两阶段优化方法，该方法将网架重构及负荷恢复问题解耦为基于直流潮流的混整线性规划和基于交流潮流的连续非线性规划两阶段优化问题。在第1阶段优化中，利用计及频率影响的直流潮流模型确定最优线路投运及负荷开关投切状态这些离散变量的值，再将其作为第2阶段基于增广交流潮流的连续非线性规划的系统运行条件，通过优化发电机出力及端电压，在确保系统安全的前提下确定最短的恢复耗时。在10机39节点系统下进行了算法验证，计算得到单步和全过程下的计算效率和恢复方案，结果表明，所提算法的计算效率远高于启发式算法，同时所得方案也具有更快的恢复速度。最后，以湖北电网鄂东南子网为例验证该算法用于实际电网恢复决策的可行性。“,”ABSTRACT:Network and load recovery (NLR) during power system restoration is a complex mixed-integer nonlinear optimization problem, which is difficult to be solved efficiently. To reduce the difficulty and improve the efficiency, this paper proposes a two-stage optimization method to decouple the NLR into a mixed-integer linear optimization problem and a continuous nonlinear optimization problem. In the first stage, the optimal plan for transmission line charging and load pick-ups is determined by mixed-integer linear programming (MILP) based on the DC power flow with frequency characteristics. Then in the second stage, an expanded AC power flow based continuous nonlinear optimization model is established to minimize the recovery time based on the optimal plan determined in the first stage. The 10-machine 39-bus system is used to analyze the efficiency and characteristics of a restoration plan in both single step and whole restoration process. Analysis results reveal that the restoration plans obtained from the proposed method are more efficient than those obtained by heuristic algorithms, while computation time is greatly reduced. Finally, the feasibility of applying the proposed method in a real power grid is validated through the Hubei Southeast Power Grid.