Abstract The on-line diagnosis can be defined as a sequence of operations designed to detect, to isolate an anomaly and to mitigate its impact before it affects the inspected system. In the context of the project ALPES 2 (local accidents – protection and monitoring, in English) of the GIS 3SGS (group of scientific interest – surveillance, dependability, security of large systems, in English), the statistical methods for the early detection of a Total Instantaneous Blockage (TIB) occurred in a single subassembly of a sodium-cooled fast reactor have being studied. This work is carried out within the framework of model-based detection methods. The goal of this paper is to study the feasibility of a sequential approach to detect an abnormal local temperature rise of neighboring subassemblies due to a TIB while respecting the probability of missed detection, the probability of false alarm and the required time-to-alert. The adaptive statistical estimation/detection method is based on the measurements taken from ThermoCouples (TCs) located above the subassemblies. The aim is therefore to provide a complementary tool to improve the early detection of a TIB in the context of nuclear safety.

中文翻译：

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在钠冷快堆的单个组件中发生总瞬时阻塞的顺序检测

摘要 在线诊断可以定义为一系列操作，旨在检测、隔离异常并在其影响被检查系统之前减轻其影响。在 GIS 3SGS（科学兴趣组 - 大型系统的监视、可靠性、安全性，英文）的 ALPES 2（本地事故 - 保护和监测，英文）项目的背景下，早期检测的统计方法a 正在研究钠冷快堆的单个组件中发生的总瞬时阻塞（TIB）。这项工作是在基于模型的检测方法的框架内进行的。本文的目的是研究顺序方法的可行性，以检测由于 TIB 引起的相邻子组件的异常局部温升，同时考虑漏检概率、误报概率和所需的警报时间。自适应统计估计/检测方法基于从位于子组件上方的热电偶 (TC) 进行的测量。因此，目的是提供一种补充工具，以改进核安全背景下 TIB 的早期检测。