基于最小割集的系统可靠性预计

Reliability Prediction Model Based on Minimal Cut Sets

运用故障树分析法求解出设备冷却水系统的最小割集,由于此系统可靠性可以用其最小割集组合的可靠性来表示,假设系统的设备之间具有失效相关性,显然其最小割集内设备故障之间也具有失效相关的特性,针对设备之间存在失效相关性的情况,使用Copula函数刻画最小割集内设备故障之间的失效相关性,建立设备冷却水系统的可靠度预计模型并进行定量计算。分析结果表明,系统采用冗余设备的可靠度比无冗余情况的可靠度高,但设备之间的失效相关性使系统的可靠度降低了。也说明了该模型可以较好地解决设备冷却水系统的可靠性预计问题。

This paper uses the FTA （fault tree analysis） to solve the minimal cut sets of CCWS, and relia bility of the system can be represented as a generalized mixture of the minimal cut sets reliability. Assum ing that there is correlation between the equipment in the system, clearly there is also the correlation be tween the equipment failures of minimal cut sets. According to this situation, this paper uses Copula to de scribe correlation between the equipment failures of minimal cut sets, establishes the reliability prediction model of CCWS and does the quantitative calculation. The results shows that the reliability of redundancy system is much higher than that of single equipment, but the dependent failures between equipment de crease the reliability of system. And also it shows that this model can be perfectly used in the reliability prediction of CCWS.