The application relates to the technical field of fault diagnosis, and provides a high-frequency
transformer fault diagnosis method and
system, which comprises the following steps: collecting a
target signal with a time stamp and extracting corresponding features, simultaneously relying on a
transformer structure, material parameters and physical rules to build a digital twin model, simulating insulation and structure degradation equivalent working conditions, solving multi-
physical field data and generating multi-
physical field mechanism samples; then, the mechanism samples and field measured data are fused through a
generative adversarial network to expand the fault sample
data set and solve the sample scarcity problem; in the running stage, the digital twin model is updated in real time through parameter online inversion, a feature dynamic graph representing multi-physical
coupling is constructed by combining the parameter deviation of internal mechanism degradation and the multi-source features of external working conditions, finally, the
feature aggregation and
time sequence reasoning are completed through the graph neural network and the
time sequence neural network trained offline, the
fault probability is output, and the optimal diagnosis result is determined; thereby, the
fault recognition accuracy and the robustness in the running stage are improved.