基于多故障冲击模型和故障树的PFDavg计算方法研究  

Research on calculation method of PFDavg based on multiple error shock model and fault tree

作　　者：赵智聪 靳江红[2] 王庆[1] 王妤甜[2] ZHAO Zhicong;JIN Jianghong;WANG Qing;WANG Yutian(School of Management and Engineering,Capital University of Economics and Business,Beijing 100071,China;Beijing Municipal Institute of Labor Protection,Beijing 100054,China)

机构地区：[1]首都经济贸易大学管理工程学院,北京100071 [2]北京市劳动保护科学研究所,北京100054

出　　处：《中国安全生产科学技术》2021年第4期42-46,共5页Journal of Safety Science and Technology

基　　金：“十三五”国家重点研发计划项目(2018YFC0808904)。

摘　　要：为提高安全仪表功能(SIF)要求时危险失效平均概率(PFDavg)计算结果的精确度,提出1种能准确计算SIF在多重共因失效影响下的PFDavg的数学模型。建立包含多重共因失效的系统失效故障树,然后利用多故障冲击模型区分普通失效率和多重共因失效率,根据瞬时不可用率的定义和故障树的逻辑关系计算出SIF的瞬时不可用率;基于PFDavg的定义,计算出SIF的PFDavg,以某化工企业SIF为例进行验证。结果表明:方法有效考虑了多重共因失效对SIF的影响,通过模型计算出SIF的PFDavg大于基于马尔可夫(Markov)方法的软件计算结果,但二者处于相同的数量级。模型在评估SIF的PFDavg时比传统方法偏保守,能提高安全仪表功能的安全性。In order to improve the accuracy of the calculation results of average probability of dangerous failures on demand(PFDavg)in the safety instrument function(SIF),a mathematical model for accurately calculating the PFDavg of SIF under the influence of multiple common cause failures was proposed.A fault tree of system failure containing multiple common cause failures was established.Then,the multiple error shock model(MESH)was used to distinguish the common failure rates from multiple common cause failure rates,and the instantaneous unavailability of SIF was calculated according to the definition of instantaneous unavailability and the logical relationship of fault tree.According to the definition of PFDavg,the PFDavg of SIF was calculated and validated by taking the SIF of a chemical enterprise as an example.The results showed that the method effectively considered the influence of multiple common cause failures on SIF,and the PFDavg of SIF calculated by the model was greater than that calculated by the software based on Markov method,but they were in the same order of magnitude.The model was more conservative than the traditional method in evaluating the PFDavg of SIF,which can improve the safety of SIF.The failure probability of component caused by each fault impact should be further studied precisely.

关 键 词：安全仪表功能(SIF) 要求时危险失效平均概率(PFDavg) 多重共因失效 多故障冲击模型(MESH) 故障树模型(FTA) 

分 类 号：X913[环境科学与工程—安全科学]