Abstract:Aiming at the problem that the vibration signal of the check valve is easily overwhelmed by noise and the fault characterization is not obvious. A fault diagnosis method for the check valve based on the total variation denoising and recurrence quantification analysis (TVDRQA) was proposed. Firstly, the total variation denoising method was used to denoise vibration signals and improve their signaltonoise ratios; Then, draw a recurrence plot on the denoised signal, extract the nonlinear characteristic parameters in the recurrence plot through the recurrence quantification analysis method, and perform sensitivity analysis on the extracted feature parameters to find out the feature vectors with higher sensitivity; Finally, the obtained feature vector is input into the weighted Knearest neighbor classifier (WKNN) to complete the identification of the check valve failure type. Experimental results show that the method has obvious effects in reduce background noise, digging fault information, and ensuring the accuracy of fault diagnosis, and has certain engineering application value.