摘要
在阐述小波变换原理的基础上介绍了两种局部放电检测的软阈值消噪方法:Stein无偏风险阈值法和平均阈值法,并利用MATLAB对加入白噪声的局部放电信号模型进行仿真研究。结果表明,stein无偏风险阈值法对单指数振荡局部放电模型消噪效果好,但对于其他三种局放模型,波形失真严重,滤噪效果较差;利用平均阈值法能更好地实现从白噪声干扰中提取原信号。
Describing the decomposition and reconstruction algorithm of the wavelet transform, two of the de-noising methods which are unbiased risk estimation based on Stein and average estimation with soft threshold operation on PD （partial discharge）detection are introduced. The simulation with MATLAB on PD signal added white noise is studied. The simulation results show that the method based on stein unbiased risk estimation has a good effect on de-noising of single index oscillation PD model, but the waves of another three PD models are serious distorted and the de-noising effects are weak. With the help of the average threshold estimation method, it can extract original signal better from the white noise interference.
出处
《电瓷避雷器》
CAS
2008年第6期17-21,共5页
Insulators and Surge Arresters
关键词
小波变换
局部放电
软阈值消噪
MATLAB仿真
wavelet transform
partial discharge
wavelet threshold de-noising
MATLAB simulation
