Research on extraction of partial discharge feature signal based on complex wavelet for power transformer

The paper presents an approach to realize the complex wavelet method which used in extracting PD (partial discharge) signal features of power transformer. Real wavelet transformation (RWT) is used to analyze and process the signals from the weak insulation in the transformer. But RWT just only extract the eigenvalue of PD signal from real part. Complex wavelet transformation (CWT) can extract the eigenvalue from both real part and imaginary part. In this way, the eigenvalue of the PD signal will contain the information from two spaces, and enhance the accuracy of analysis.