Research on Denoising of Partial Discharge Signals in Converter Valves Based on Improved Wavelet Threshold

Converter valves is one of the key equipment in the power system, and online monitoring of partial discharge is one of the important means to evaluate the operating status of converter in real-time. This paper introduces two improved methods proposed domestically and internationally and proposes a new threshold denoising function to remove interference in partial discharge signals of converter valves. The simulation experimental results of signal denoising show that these improved methods have better denoising performance than the soft threshold function and the hard threshold function. Among these five threshold functions, the newly proposed threshold function can achieve the best denoising effect by simply changing the variable parameter and is more flexible than traditional threshold functions. It provides a new choice for wavelet threshold denoising, allowing the advantages of wavelet threshold denoising methods to be more fully demonstrated.