Modeling of PWR Plant by Multilevel Flow Model and its Application in Fault Diagnosis

Abstract

The paper describes the application of Multilevel Flow Modeling (MFM)-amodeling method in means-end and part-whole way, in interface designof supervisory control of Pressurized Water Reactor (PWR) plant,and automatic real-time fault diagnosis of PWR accident. The MFMdecomposes the complex plant process from the main goal to each componentat multiple levels to represent the contribution of each componentto the whole system to make clear how the main goal of the systemis achieved. The plant process is described abstractly in functionlevel by mass, energy and information flows, which represent theinteraction between different components and enable the causal reasoningbetween functions according to the flow properties. Thus, in theabnormal status, a goal-function-component oriented fault diagnosiscan be performed with the model at a very quick speed and abnormalalarms can be fully explained by the reasoning relationship of themodel. In this paper, an interface design of the PWR plant is builtby the conception of means-end and part-whole by using MFM, and severalsimulation cases are used for evaluating the fault diagnosis performance.The results show that the system has a good ability to detect anddiagnose accidents timely before reactor trip.