基于小波阈值方法的电能质量扰动去噪分析

De-noising Analysis of Power Quality Disturbance Based on Wavelet Threshold

在小波变换的基础上,分析了硬阈值和软阈值去噪方法的不足,提出了一种新的基于小波分解和小波重构的阈值去噪方法———软硬阈值折衷方法。该方法将小波系数经过软硬阈值折衷法处理后,可以改善小波系数在阈值处的连续性,使重构信号不会振荡,又使变换后的重构信号与实际信号误差最小。通过仿真验证,该算法可以获得很好的去噪效果,消除扰动检测中的噪声影响,从而为噪声环境中电能质量扰动的检测和定位提供了良好的依据。

Based on the wavelet transform（WT） technology ,this paper analysis the deficiency of hard-threshold and soft-threshold ,proposes an new threshold method based on the wavelet decompound and reconfiguration ——the incorporation of soft-threshold and hard-threshold. The WT coefficient disposed by the compromise of the hard and soft threshold method can reform its continuity on the threshold and guarantee the reconstituted single unable to surge, also can make the signal error smallest. The results of the simulation verifies that the incorporation of soft- threshold and hard-threshold can obtain favorable de-noising purpose and eliminate noise＇s infection, consequently provide favorite warrant for the detection and location of the disturbance of power quality in the noise circumstance .