考虑多重故障的连锁过载分析

Analysis on Cascading Overload Considering Multiple Failures

多重故障作为低概率、高风险故障在一定情况下是有必要考虑的,其发生概率及严重程度随设备检修操作而引起的运行方式的改变而变化。文章采用事件树对连锁故障的分析方法,运用小概率事件的概率近似理论对多重故障进行概率阶次划分,可以简化多重故障的筛选过程。将此方法应用于连锁过载分析中,通过算例仿真可以看出,该搜索方法可以很好地反映因运行方式变化而产生的故障概率变化,更好地评估检修操作风险,进一步完善了低概率、高风险的连锁故障路径搜索,对于深入研究连锁故障有一定帮助。

As a low-probabilistic and high-risk failure, the multiple failures is necessary to take into account under a certain condition, and the occurrence probability and severity of multiple failures are varies with the change of operating mode caused by equipment maintenance. In this paper the event tree is used in the analysis on cascading failures and by use of probability approximation theory of rare event the probability order of multiple failures is divided, thus the screening process of multiple failures can be simplified. Applying this method to the analysis on cascading overload and from the case simulation results it can be seen that the proposed searching method can reflect the variation of failure probability caused by the change of operating mode well, and assess the risk of equipment maintenance better, thus the path searching of low-probabilistic and high-risk cascading failures can be further improved. The proposed method may be helpful for the research on cascading failures in depth.