Tracking and Identifying CRDM Degradation State Based on SWT and Phase Space Warping

Abstract

The control rod drive mechanism (CRDM) is important for ensuring the normal operation and safety of reactors. Considering the low speed, latent performance degradation signs, and susceptibility to interference from other signal sources of the CRDM, this paper tracks and identifies the CRDM degradation state by a combination of the semi-soft wavelet threshold (SWT) and phase space warping (PSW). By comparison with the method based on the root mean square (RMS) of vibration amplitude, the method combining the SWT with PSW, unlike the traditional linear signal processing theory with poor performance in tracking and identifying the latent performance degradation state, can track and identify adequately the performance degradation state of rotating machinery with high background noise.