Research on Roller Status Diagnosis of CRDM Based on SWT and HHT

Abstract

For the control rod drive mechanism roller vibration signal’s characteristics of nonlinear and nonstationary. Based on actual equipment life experiment and roller fault experiment, a status diagnosis method of roller of control rod drive mechanism based on Semi-soft wavelet threshold and Hilbert-Huang transform is proposed. Firstly, semi-soft wavelet threshold method is used to reduce noise interference and the influence of end-point effect on empirical mode decomposition, and the improved Hilbert transform method is used to extract the fault characteristics of roller vibration signal. The experimental results show that the method can effectively eliminate the interference of noises and realize the status diagnosis of the roller.