Application of Fault Tree Analysis Technique to Predict Instrumentation System Failure and Define Problem Areas in a Nuclear Power Plant Containment Study

Abstract The safe and secure designs of any nuclear power plant together with its cost-effective operation without accidents are leading the future of nuclear energy. As a result, the Reliability, Availability, Maintainability, and Safety analysis of NPP systems is the main concern for the nuclear industry. But the ability to assure that the safety-related system, structure, and components could meet the safety functions in different events to prevent the reactor core damage requires new reliability analysis methods and techniques. The Fault Tree Analysis (FTA) is one of the most widely used logic and probabilistic techniques in system reliability assessment nowadays. The Dynamic fault tree technique extends the conventional static fault tree (SFT) by considering the time requirements to model and evaluate the nuclear power plant safety systems. Thus this paper focuses on developing a new Dynamic Fault Tree for the Auxiliary Feed-water System (AFWS) in a pressurized water reactor. The proposed dynamic model achieves a more realistic and accurate representation of the AFWS safety analysis by illustrating the complex failure mechanisms including interrelated dependencies and Common Cause Failure (CCF). A Simulation tool is used to simulate the proposed dynamic fault tree model of the AFWS for the quantitative analysis. The more realistic results are useful to establish reliability cantered maintenance program in which the maintenance requirements are determined based on the achievement of system reliability goals in the most cost-effective manner.

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Application of Fuzzy Fault-Tree Analysis to Assess the Reliability of a Protection System for a Switchyard

International Journal of Emerging Electric Power Systems ◽

10.2202/1553-779x.1944 ◽

2008 ◽

Vol 9 (4) ◽

Cited By ~ 1

Author(s):

Ying-Yi Hong ◽

Lun-Hui Lee ◽

Heng-Hsing Cheng

Keyword(s):

Power Plant ◽

Fuzzy Set ◽

Nuclear Power ◽

Fault Tree ◽

Reliability Assessment ◽

Fault Tree Analysis ◽

Protection System ◽

Importance Measure ◽

Tree Analysis ◽

Fuzzy Fault Tree Analysis

This paper proposed a method for reliability assessment of the protection system for a switchyard by fault-tree analysis considering uncertainty of unavailability for an element. Unavailability of an element with uncertainty is expressed with the fuzzy set. The fault-tree analysis incorporated with the fuzzy set is employed to conduct the reliability assessment. The importance of elements influencing reliability can be achieved by the Fuzzy Importance Measure. Compared with traditional methods, the fault-tree analysis requires less computation. In this paper, a 345 kV switchyard in the 3rd nuclear power plant in Taiwan serves as an example for illustrating the results of the proposed method.

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Basic Fault Tree Analysis Technique

Risk Assessment ◽

10.1002/9781119483342.ch14 ◽

2019 ◽

pp. 185-202

Keyword(s):

Fault Tree ◽

Fault Tree Analysis ◽

Tree Analysis ◽

Analysis Technique ◽

Basic Fault

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Nuclear Power Plant Cyber Security Discrete Dynamic Event Tree Analysis (LDRD 17-0958) FY17 Report

10.2172/1395751 ◽

2017 ◽

Author(s):

Timothy A. Wheeler ◽

Matthew R. Denman ◽

R. A. Williams ◽

Nevin Martin ◽

Zachary Kyle Jankovsky

Keyword(s):

Power Plant ◽

Nuclear Power Plant ◽

Cyber Security ◽

Nuclear Power ◽

Event Tree ◽

Event Tree Analysis ◽

Tree Analysis ◽

Discrete Dynamic ◽

Dynamic Event

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U.S. Nuclear Power Plant Performance Assessment Using the Versatile Economic Risk Tool (VERT)

10.1115/icone28-65769 ◽

2021 ◽

Author(s):

Jaden C. Miller ◽

Spencer C. Ercanbrack ◽

Chad L. Pope

Keyword(s):

Risk Assessment ◽

Power Plant ◽

Nuclear Power Plant ◽

Nuclear Power ◽

Fault Tree ◽

Plant Performance ◽

Economic Risk ◽

Reliability Data ◽

Water Reactor ◽

Tree Models

Abstract This paper addresses the use of a new nuclear power plant performance risk analysis tool. The new tool is called Versatile Economic Risk Tool (VERT). VERT couples Idaho National Laboratory’s SAPHIRE and RAVEN software packages. SAPHIRE is traditionally used for performing probabilistic risk assessment and RAVEN is a multi-purpose uncertainty quantification, regression analysis, probabilistic risk assessment, data analysis and model optimization software framework. Using fault tree models, degradation models, reliability data, and economic information, VERT can assess relative system performance risks as a function of time. Risk can be quantified in megawatt hours (MWh) which can be converted to dollars. To demonstrate the value of VERT, generic pressurized water reactor and boiling water reactor fault tree models were developed along with time dependent reliability data to investigate the plant systems, structures, and components that impacted performance from the year 1980 to 2020. The results confirm the overall notion that US nuclear power plant industry operational performance has been improving since 1980. More importantly, the results identify equipment that negatively or positively impact performance. Thus, using VERT, individual plant operators can target systems, structures, and components that merit greater attention from a performance perspective.

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