Detecting transformer winding deformation fault types based on continuous wavelet transform

摘要

When online detecting transformer winding deformation with impulse frequency response analysis, the time domain characteristics of transient signal could not be depicted by conventional frequency response curves, and the limitations of Fast Fourier Transform could result in deletion of available information. In this paper, continuous wavelet transform is used to process transient signal, which is obtained by online impulse signal injection method, time-frequency spectrum of wavelet transform is studied to detect transformer winding deformation fault types. A single winding simulation model is constructed after theoretical deduction, the simulation analysis of different fault types is performed, the typical winding fault test is conducted, the time-frequency characteristic of detection signal is analyzed, the matrix similarity is used to quantize the diversity of the detection signal. Both the simulation analysis and experimental studies show the feasibility of the proposed method.