考虑共因失效的系统安全性评估  

Safety Assessment of Systems in Presence of Common Cause Failures

作　　者：曹策 王鹏[1] 白焰[2] 唐艳梅 付亚利[2] 

机构地区：[1]天津科技大学电子信息与自动化学院,天津300222 [2]华北电力大学控制与计算机工程学院,北京102206

出　　处：《数学的实践与认识》2017年第23期97-107,共11页Mathematics in Practice and Theory

摘　　要：随着工业产品复杂程度的提高,安全性已成为系统设计的重要指标.考虑共因失效因素,根据同时发生故障的单元数目对故障率进行区分,首先,针对串联、并联、n取k等典型系统结构,分别建立故障树,推导平均要求时失效概率(PFD_(avg))及安全失效概率(PFS)的通用计算公式;其次,与IEC61508基于简单β因子模型提出的n取k系统的PFD_(avg)计算公式比较,证实该方法的通用性及精确性;最后,通过实例验证,对DCS系统紧急跳闸按钮的不同设计方案进行安全性分析,证实方法的有效性.With the increased complexity of industrial products, safety has become an important index for system design. Common-cause failure is considered in this paper, and failure rates are divided by the number of units which fail at the same time. Firstly, for typical system structures of series, parallel, and n out of k, fault tree models are established, and the average probability of failure on demand（PFD_（avg）） and probability of fail safety（PFS） are calculated, respectively; Secondly, compared with formulas of PFD_（avg） proposed by IEC61508 based on simple β-factor model, this method is proved more general and accurate; Finally,with example verification, safety analysis for different designs of emergency trip button in DCS system confirm the method is effective.

关 键 词：共因失效 安全性 平均要求时失效概率 安全失效概率 故障树 

分 类 号：O213[理学—概率论与数理统计]