Construction and evaluation of fault detection network for signal validation

The authors present a method for evaluating and constructing a sensor failure detection network for nuclear power plant signal validation. The network is arranged in a fault tree structure which consists of sensors, mathematical models for sensor relations, and decision/estimators derived from parity relations. The evaluation scheme performs a logic state analysis to categorize critical signals and the associated sensors. The construction scheme cooperates with the evaluation scheme to build a detection network automatically using a rule-based algorithm. The package was implemented on a microcomputer, and was demonstrated for the nuclear steam supply system of a pressurized water reactor (PWR) plant