基于输配全局的城市电网供电能力研究

提出一种基于输配全局的城市电网供电能力分析模型。采用基于直流潮流的线性规划模型对城市电网输电网络供电能力进行求解并将其作为系统上层约束；将传统配电网模型细化至中压馈线，分别构建高、中压配电网供电能力模型；计算N-1安全约束下高压配电线路、中压配电变压器及中压配电线路在不同转供方式下对应的最大供电能力，选取其中最小值作为系统最大供电能力。算例结果表明：基于输配全局的分析方法可以有效量化输电网对城市电网供电能力的影响，同时根据不同转供方式下的供电能力差异能够直观地对变压器故障情况下的负荷转移方式做出选择，验证了所提模型的有效性。

Power supply capability of urban transmission and distribution power system

An analysis model of power supply capability for urban transmission and distribution power grid is proposed. The power supply capability of transmission network in urban power grid is solved with the liner programming model based on direct current power flow, and is taken as the system upper constraint. The traditional distribution model is refined to the medium voltage feeder, and the power supply capability models of high and medium voltage distribution network are established respectively. The maximum power supply capabilities of high voltage distribution lines, medium voltage distribution transformers and medium voltage distribution lines are calculated under different transfer modes under the N-1 safety constraints, the minimum value of which is selected as the maximum power supply capability of the system. The case results show that the proposed method can effectively quantify the influence of transmission network on the power supply capability of urban power grid, and the load transfer mode in the case of transformer failure can be intuitively selected according to the difference of power supply capability under different transfer modes, and the validity of the proposed model is verified.