On-line failure detection in nuclear power plant instrumentation

The functional redundancy approach to detecting instrument failures in nuclear power plant instrumentation is described and evaluated. This real-time method uses a bank of Kalman filters (one for each instrument) to generate optimal estimates of the plant state. By performing consistency checks between the output of each filter, failed instruments can be identified. The technique is used to design an instrument failure detection system for a pressurized water reactor (PWR) pressurizer. Actual pressurizer data are used to demonstrate the capabilities of the functional redundancy methods.