Research And Development Of Automatic Fault Tree Synthesis System

Nowadays, computer-aided fault tree synthesis has been given abroad attention. To make fault tree much easier to read and make fault-tree more simplified to synthesis, an Automatic Fault Tree Synthesis System (AFTSS) is developed in this paper, which realizes resource sharing.The algorithm in the system is based on system analysis. A database, describing cause-effect models of components and control loops, is first built according to the properties of the components and the control loops. According to flow chart of the process control system, the basic information, which concerns absolute components, control loops and uncontrollable disturbances from outside, can be attained. And they are treated as sub-elements. During fault tree synthesis, adjacency matrix is worked out from flow chart and graph of the control system. This adjacency matrix describes the direct relationships among each item of elements in the process control system. Also, it can be used to work out the reachable matrix. System analysis is applied to the reachable matrix. As a result, the fault tree frame model of the process control system is obtained, and the top structure in sequence. Finally, by searching each node in the top structure along with frame model, correlative cause-effect model in database is employed to construct fault tree automatically.As far as AFTSS concerned, it is composed of User Login, Fault Tree Model, Control System, Fault Tree Synthesis, and Technique Forum. User register, log on, and manage materials in User Login. Cause-effect models of components and control loops fault tree model is created and edited in Fault Tree Model. Control Systems creates and edits control system. Fault Tree Synthesis is to construct fault tree of one control system automatically. Technique forum supply a place for users to discuss the technology of fault tree synthesis.The nitric acid cooling system, as an example, is provided in the paper to prove this algorithm validity and feasibility. The fault tree synthesized by this system is much more concise and easier to read. AFTSS avoids the repeated work, strengthens theoretic basis of the fault tree. Undoubtedly, it will have better future for application.