The Fault Detection Method of Transformer Winding Oscillatory Wave Based on Discrete Wavelet

To further improve the efficiency and reliability of transformer winding state detection, this paper proposes a method for detecting transformer winding oscillating wave faults based on correlation coefficients and discrete wavelet transform (DWT), and a 10 kV transformer winding fault simulation test platform is built for experimental analysis. Through filtering and discrete wavelet transformation of the measured data, the discrete wavelet detail signal which can be used to evaluate the characteristics of the oscillatory wave is obtained. Finally, the experimental analysis of the oscillatory wave under the normal and fault conditions of the winding is carried out. The results show that the self-excited oscillatory wave characteristics obtained by discrete wavelet transform have good repeatability and can reflect the difference between windings. When the axial displacement and parallel capacitance fault occur, the characteristics change obviously, which can provide a reference for transformer winding fault detection.