Abstract Passive safety systems are being considered in advanced reactor designs to provide inherent stability for the operation of the nuclear reactor. Passive shutdown is provided for guaranteed removal of decay heat under emergency conditions. The reliability of such systems should be very high. The static reliability assessment of such systems has been considered using various techniques such as fault tree analysis, failure mode effect analysis, and reliability block diagrams. Dynamic reliability methods are powerful mathematical frameworks capable of handling interactions among components and process variables explicitly. In principle, they constitute a more realistic modelling of systems for the purposes of reliability, risk and safety analysis. Although there is a growing recognition in the risk community of the potentially greater correctness of these methods, no serious effort has been undertaken to utilize them in industrial applications. The dynamic flowgraph methodology is an integrated methodological approach to modelling and analyzing the behavior of software-driven embedded systems for the purpose of reliability/safety assessment and verification. In the present work, dynamic flowgraph methodology has been used to analyze the Station Blackout Scenario for a Nuclear Power Plant. The benefits of the proposed method are brought out with respect to the traditional methods like fault tree analysis, which deteriorates in applicability with increasing system size and complexity and fails to accommodate the dynamics of the system. The proposed method has been validated on the passive residual heat removal system of pressurized heavy water reactor.

中文翻译：

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使用动态流程图方法的核电厂动态可靠性框架

摘要 在先进的反应堆设计中正在考虑被动安全系统，以便为核反应堆的运行提供固有的稳定性。提供被动关闭以保证在紧急情况下去除衰变热。这种系统的可靠性应该非常高。此类系统的静态可靠性评估已考虑使用各种技术，例如故障树分析、故障模式影响分析和可靠性框图。动态可靠性方法是强大的数学框架，能够明确处理组件和过程变量之间的相互作用。原则上，出于可靠性、风险和安全分析的目的，它们构成了更现实的系统建模。尽管风险社区越来越认识到这些方法可能具有更大的正确性，但尚未认真努力将它们用于工业应用。动态流程图方法是一种集成的方法论方法，用于对软件驱动的嵌入式系统的行为进行建模和分析，以进行可靠性/安全性评估和验证。在目前的工作中，动态流程图方法已被用于分析核电厂的电站停电情景。与故障树分析等传统方法相比，该方法的优点是随着系统规模和复杂性的增加而降低适用性，并且无法适应系统的动态性。