Solid-state power distribution unit fault diagnosis method, system and equipment

The invention discloses a solid-state power distribution unit fault diagnosis method, system and device, and relates to the field of fault diagnosis of power electronic products, and the method comprises the steps: constructing a solid-state power distribution unit electrothermal coupling model; based on the solid-state power distribution unit electrothermal coupling model, collecting signals under normal conditions and when different fault types occur, and constructing a fault signal data set; constructing a PCA-ELM (Principal Component Analysis-Extreme Learning Model) model by using MATLAB (Matrix Laboratory), and training the PCA-ELM model by adopting the fault signal data set; and performing fault diagnosis on the actually measured signal of the actual solid-state power distribution unit through the trained PCA-ELM model. The real working state of the solid-state power distribution unit circuit is accurately simulated by simulating the electrothermal coupling effect, and the electric signal and the temper