Computer Aided Fault Tree Analysis Algorithm For Process System

Nowadays, Fault Tree Analysis (FTA) has been widely used in the reliability design, fault diagnosis and testing design of a complicated system. However, the construction of the system's fault tree is the basic premise of FTA; it also affects the promotion and application of FTA. Because of the deficiencies of the manual fault tree synthesis and the rapid development of computer technology, the research of the computer aided fault tree synthesis is of widespread applied value, and has turned into one of the people's burning issues.Combined with the research and analysis of the existing methods and based on the thought of system decomposition, a new method of computer-aided fault tree synthesis aimed at process system is proposed in this paper. Its main idea is:firstly, define the top event for the whole system's fault tree, decompose the objective system into several subsystems (control loop). Secondly, construct the top structure model of a fault tree for each control loop, and use the Interpretive Structural Modeling method to generate the sub-fault tree for some developable events in the top structure model. Thirdly, connecting the top structure model with the sub-fault tree, we can get the whole fault tree of a control loop. Finally, synthesize the fault tree of all the control loops, simplify it, and then deduce the event status of fault tree, so we get the whole fault tree of the system. The method we proposed simplified the process of constructing a fault tree for the large industrial systems to a certain extent; it also eases the work intensity for engineering and technical personnel. The method is easily to understand and implement, the fault tree it generated is convenient for understanding and analysis.Moreover, using the Visual Basic6.0 software a set of system platform was developed for constructing in this paper. This platform implemented the method above, and has advantages of friendly interface, easily operating and fast running. Finally, a nitric acid cooling system which was applied to the method, proved the feasibility and availability of the system. The method proposed in this paper improved the automation of fault tree constructing and has certain utility and better future for application.