Academic Articles | |||||
Regular Paper | Vol.6 No.3 (2014) p.71 - p.85 | ||||
Diagnostic Agent using Parasitic Discrete Wavelet Transform for the Hybrid Diagnostic Agent System for the Fast-breeder Reactor “Monju” |
|||||
Takashi NAGAMATSU1, Yuki JOU2, Akio GOFUKU3, Takayuki FUJINO3, Zhong ZHANG4 | |||||
1 Graduate School of Maritime Sciences, Kobe University, 5-1-1 Fukae-minami, Higashi-nada, Kobe 658-0022, JAPAN 2 Faculty of Maritime Sciences, Kobe University, 5-1-1 Fukae-minami, Higashi-nada, Kobe 658-0022, JAPAN 3 Graduate School of Natural Science and Technology, Okayama University, 3-1-1 Tsushima-Naka, Kita-ku, Okayama 700-8530, JAPAN 4 Faculty of Maritime Sciences, Kobe University, 5-1-1 Fukae-minami, Higashi-nada, Kobe 658-0022, JAPAN |
|||||
Abstract | |||||
In order to detect anomalies in rotating machines such as pumps at an early stage, we developed a system using wavelet transform. The pump diagnostic experiment equipment was designed taking into consideration the structure of the pump used for the water-steam system of the fast breeder reactor “Monju”. For improving detection capability, it is desirable to use a mother wavelet (MW) whose shape is similar to the anomaly signal that is required to be detected. We call the constructed MW on the basis of the real signal the real mother wavelet (RMW). The parasitic discrete wavelet transform (P-DWT) that has a large flexibility in design of the MW and a high processing speed was applied for detecting process signals. The vibration and sound signals were measured using the pump diagnostic experiment equipment when three types of anomalies (injection of an object, change of a balance of the impeller, and damage to the axis of the impeller) occur. Complex RMWs were constructed on the basis of the measured signals, and subsequently, parasitic filters were constructed. Signal detection was performed by calculating the fast wavelet instantaneous correlation using the parasitic filter. We evaluated three types of anomalies, and found that P-DWT is useful for detecting these anomalies. Furthermore, we developed a diagnostic agent using P-DWT as one of the diagnostic agents of our hybrid diagnostic agent system, which is intended to work together with the “Monju” distributed diagnostic agent system. |
|||||
Keywords | |||||
Wavelet transform, parasitic discrete wavelet transform, complex real mother wavelet, Monju | |||||
Full Paper: PDF
|
|||||