Fault diagnosis system and fault diagnosis method based on sequence and consequence analysis of event tree

Abstract

The invention discloses a fault diagnosis system and a fault diagnosis method based on sequence and consequence analysis of an event tree. The system comprises a data input module, an event tree resolution module, a fault tree preprocessing module, a fault tree analysis module and a diagram display module, wherein the data input module is used for acquiring reliability data and structure data of a given system, and storing the data in modes of a fault tree model and an event tree model; the event tree resolution module is used for processing the given event tree model and the fault tree model, processing a successful branch of the event tree with a respective substitution method, and constructing a traditional sequence fault tree model and a consequence fault tree model; the fault tree preprocessing module is used for preprocessing the given fault tree model; the fault tree analysis module is used for performing fault mode analysis, probability computation, importance computation, sensitivity computation and uncertainty analysis on the given fault tree model; and the diagram display module is used for displaying a fault analysis result of the given system in a diagram form. The system and the method can accurately construct sequence and consequence fault trees, and perform various approximate computation and accurate computation on the successful branch of each function event of the event tree, so that the reliability is improved.

Description

technical field [0001] The invention relates to a fault judgment system and method based on event tree sequence and consequence analysis, belonging to the field of reliability and safety evaluation. Background technique [0002] Event Tree Analysis (Event Tree Analysis) is a temporal logic accident analysis method, which is usually used in the safety evaluation and reliability analysis of nuclear power systems and other large complex systems. An important part of the Assessment). It analyzes various accident sequences formed by the combination of the initial event (Initial Event, also known as "initial event") and the relevant power plant system response, and then establishes an event tree (ie, an event tree model). These related power plant systems are represented as functional events (Function Event, also called "head event") in the event tree, and the accident sequence is represented as a sequence of event trees in the event tree model. According to the success or failu...

AI Technical Summary

Problems solved by technology

[0003] When analyzing the event tree, it is easier to calculate the failure branch; but it is more difficult to calculate the successful branch. Considering the time and resource consumption, the popular probabilistic safety evaluation systems at home and abroad generally do not support the successful branch. However, according to the needs of analysis accuracy, various approximate calculation methods are used. The process of building fault trees with these approximate methods is different.

The idea of ​​the traditional event tree sequence (Sequence) or consequence (Consequence) solution method is generally based on the system fault tree model corresponding to the initiating event and the functional event, and directly expands a certain sequence or consequence into an overall fault tree ( That is, the sequence fault tree model of the event tree or the consequence fault tree model of the event tree), and then they are processed uniformly, and it is not possible to perform different successful branch processing for each individual functional event according to the requirements of analysis accuracy; it is more expensive computing resources and time, or cannot meet the needs of the analysis

[0004] Some new methods developed later can process different successful branches for each individual functional event, but the method of directly building a fault tree for analysis makes tree building and analysis calculations very time-consuming, and it is difficult to handle large-scale sequences Fault tree construction and analysis tasks, especially the consequence fault tree; and once the successful processing method is changed, the fault tree needs to be rebuilt

There is also a "three-step method", which was proposed in the paper "Research on the Analysis Method of Accident Sequence Consequences in Nuclear Power Plant PSA" in Volume 42, Issue 8 of "Atomic Energy Science and Technology". It adopts an alternative method to build trees step by step, saving However, because it is a simple direct replacement, it can only be used for the failure branch of functional events, but not for the success branch, resulting in incomplete analysis of the failure mode of the system, and the obtained failure probability is different from the actual one. bigger

Images