Development of BWR Plant Diagnosis System using Noise Analysis

A diagnosis system using noise analysis technique has been developed and its diagnosis performance is tested. Diagnosis objects are reactor core, three main control systems and jet pumps in a BWR plant. This diagnosis system is composed of a minicomputer system and operator's console. The FFT (Fast Fourier Transform) method is applied for data analysis. Many data obtained during normal operations were accumulated using this system and inherent variation patterns were estimated by eliminating the effect of operating condition. Anomaly detection methods were determined on the basis of these data. It is confirmed that the performance of this system is satisfactory, and that this system will be of great use for BWR core and control systems surveillance.