The invention discloses a state monitoring and diagnosing method and
system for a marine main engine, and the method comprises the steps: collecting the operation state parameters of the marine main engine, and carrying out the preprocessing; embedding a dynamic
soft thresholding layer in each residual module of the residual shrinkage network, and executing channel-by-channel
soft thresholding on the feature map; constructing a double-flow
attention network, fusing the time-
frequency domain characteristics of the vibration signals and the temperature
field data of the space heat conduction model, and capturing a causal sequential relationship of multi-
modal data through a gating mechanism; carrying out embedded optimization on the model by adopting depth separable
convolution, adaptive load normalization and knowledge
distillation; the model is carried on a shipborne industrial
personal computer, and whether model updating needs to be triggered or not is judged by calculating the
weight difference between the shipborne model and the
global model of the cloud platform. According to the method, a whole-process
closed loop from
data acquisition to model deployment is realized, the anti-
noise capability, causal association analysis, resource optimization and
privacy protection are integrated, and the intelligent operation and maintenance requirements of the marine main engine are met.