可信度控制下的相继开断潮流快速计算

电力系统相继开断的分析面临着维数灾和交流潮流计算量大的瓶颈,分布因子法被广泛研究以减少其计算量。但由于分布因子法忽略了非线性因素,误差不但难以控制,并随相继开断不断积累,严重阻碍其实际应用。为了使开断潮流的计算兼具分布因子法的快速性和交流潮流法的精确性,基于摄动获取的二阶灵敏度,提出分布因子法的可信度指标,并据其判断是否需要运行一次交流潮流来消除累积误差。仿真实例表明,该指标能可靠地估计分布因子法的误差,而设计的计算框架则在保证精度的基础上,提升了计算效率。

A Credibility Index Based Algorithm for Fast Estimating Power Flow in Cascading Failures

Facing the scourge of dimensionality and the huge computational burden of AC power flow, the analysis of cascading failure is extensively researched as a remedy. However, owing to its neglect of the nonlinear factors, not only are errors uncontrollable, they steadily accumulate with the cascading failure seriously hampering its application. To enable power flow calculation to possess both the rapidity of distribution factor (DF) and the accuracy of AC power flow, based on the second-order sensitivity to monitoring the error obtained from perturbation, the credibility index of the DF is presented. When the index is over the threshold, AC power flow should be selected instead of DFs to eliminate the accumulated error. Then, a fast calculation algorithm is proposed to balance the accuracy and efficiency in cascading failure analysis. Simulation results show that computation errors can be evaluated by the index, and the computation efficiency is greatly enhanced while the accuracy is guaranteed. This work is supported by National Basic Research Program of China (973 Program) (No. 2013CB228204), Australian Research Council Project (No. DP120101345), NSFC-EPSRC Collaborative Project (No. NSFC-513111025-2013, No. EPSRC-EP/L001063/1), and State Grid Corporation of China.