全局输配电网电压稳定故障筛选与排序的分布式计算方法

随着传统配电网向含大量分布式电源的主动配电网转变，输电网、配电网电压稳定评估已不再适宜各自独立计算。基于输电网、配电网分属于不同控制中心调控，提出一种全局输配电网电压稳定故障筛选与排序的分布式计算方法。该方法分为两阶段：阶段1中采用输配电网主从分裂分布式潮流工具在系统要求最小负荷裕度值的工况下进行各预想故障的潮流计算，采用最优乘子法筛选出潮流不可解的严重故障；阶段2中采用基于输配电网分布式连续潮流的步长加速二次曲线拟合方法计算严重故障的负荷裕度并进行排序。由1个IEEE 118节点输电网和2个IEEE 33节点配电网组成的全局输配系统的仿真算例表明所提方法能够快速可靠地实现全局输配电网电压稳定故障筛选与排序。

Distributed calculation method of voltage stability contingency screening and ranking for integrated transmission and distribution networks

Along with the transformation from traditional distribution network to active distribution network with many distributed generators, voltage stability assessment of transmission and distribution networks is no longer suitable to calculate separately. Since transmission and distribution networks are controlled by different control centers, a distributed calculation method of voltage stability contingency screening and ranking for integrated transmission and distribution networks is proposed, which includes two stages. In Stage 1, the master-slave splitting distributed power flow tool of transmission and distribution networks is adopted for power flow calculation of each anticipated contingency under the condition of minimum load margin requirement of system, and the optimal multiplier method is used to screen out the critical contingencies whose power flow cannot be solved. In Stage 2, the load margins of critical contingencies are calculated and ranked by the look-ahead quadratic curve fitting method based on distributed continuous power flow of transmission and distribution networks. The simulation case of an integrated system composed of an IEEE 18-bus transmission network and two IEEE 33-bus distribution networks shows that the proposed method can quickly and reliably realize the voltage stability contingency screening and ranking of integrated transmission and distribution networks.