Online fault intelligent monitoring method and device for underwater propeller propeller

The invention relates to the technical field of online fault monitoring, and discloses an underwater propeller propeller online fault intelligent monitoring method and device, and the method comprises the steps: carrying out the multi-resolution decomposition of a fault detection signal, and obtaining a multi-scale decomposition sub-signal; constructing a multi-scale energy threshold function to carry out threshold denoising on the multi-scale decomposition sub-signals; and reconstructing the de-noised multi-scale decomposition sub-signals, carrying out multi-domain feature extraction, and carrying out fault detection on a fault detection signal feature vector by using an underwater propeller propeller fault detection model. According to the method, the multi-scale decomposition sub-signals are denoised based on the energy threshold value, the multi-scale decomposition sub-signals containing less energy are removed, influence weights of other scales are reduced, denoising processing of the fault detection sig