Application Of Wavelet On Status Monitoring And Failure Diagnosis Of Large Scale And Intermediate Pump

With more attachment on stability and reliability of hydropower unit, progress has been made on the status monitoring and failure diagnosis research and many monitoring methods have been put into reality. However, research on stability and reliability aiming at the intermediate and large scale pump unit is on the stage of beginning. Based on the cases above, combining the project of 948, which is a project aiming at importing advanced facilities to equip agriculture of China, in the literature theory on wavelet analysis is introduced into status monitoring and failure diagnosis of intermediate and large scale pump unit. Some fruits are as follows,1 Fundamentals on wavelet transform have been analyzed and characteristics of important wavelets have been generalized.2 Research on test objects and its locations have been made in the status monitoring and failure diagnosis of intermediate and large scale pump unit; Method on shaft and bearing measurement vibration have been pointed out, normalized energy feature extraction; characteristics of pump unit vibration signals have been generalized.3 Research on wavelet application in Pre-processing of vibration signals of status monitoring and failure diagnosis of intermediate and large scale pump unit has been made. The research turned out that in data compression aiming at the shaft vibration signal, the optimal decomposition level was 3 with the SURE threshold strategy, while in signal denoise, the optimal wavelet is Db4 with Rigrsure threshold strategy and the best decomposition level was 4.4 Research on relation between wavelet coefficient and singularity has been made. Basing on the continual wavelet transform modulus maximum theory, analysis on the main shaft vibration signal has been performed which successfully localize the time and position of shaft friction happening.