Noise Reduction of Partial Discharge Signal of High Voltage Cable based on VMD

摘要

Partial discharge (PD) is used in high-voltage cable online monitoring, the collected signal contains a variety of noises, usually periodic narrow-band interference and white noise are the most common and the most widely affected. In order to suppress the influence of complex noise, a partial discharge signal noise reduction method based on Variational Mode Decomposition (VMD) is proposed. VMD is used to decompose the noisy partial discharge signal to obtain the intrinsic mode functions (IMF) from low to high frequency, then calculate the kurtosis value of each variational modal component, the pulse characteristic component for reconstruction was select, and adaptive threshold used to reduces the noise of the reconstructed signal again. Compared with the wavelet transform threshold method, the noise reduction results are obtained in different noise environments. The results are quantitatively superior to the wavelet standard soft threshold noise reduction method and the wavelet global hard threshold noise reduction method from the mean square error and the waveform similarity coefficient. Simulation and field experiment results show that this method can effectively remove noise signals, and can retain the original signal waveform more completely, which is convenient for subsequent signal processing.