小波包去噪在暂态电能质量信号去噪中的应用

Wavelet packet denoising in the application of the transient power quality signal denoising

为了提高暂态电能质量检测的精度,就要求被检信号去噪效果达到最佳;本文通过对比小波去噪和小波包去噪的优劣性,以此选出效果较好的小波包去噪进行深层次筛选,包括对sym4小波包、sym8小波包、d B3小波包、d B5小波包去噪的效果比较,从而筛选出效果最好的sym5小波包去噪方法。该方法有效克服了小波去噪效果不佳而致使信号失真的缺点,应用范围也不仅仅局限在低频范围;除此之外,减少了去噪过程中信息损失,使信噪比和均方根误差等性能指标较之小波去噪有明显优化。

In order to improve the accuracy of transient power quality detection, requires that the effect of detected signal denoising is best; In this paper, by comparing the superiority-inferiority of wavelet denoising and wavelet packet denoising, wavelet packet denoising with better effect for deep filter, including the effect of sym4 wavelet packet, sym8 wavelet packet, d B3 wavelet packet and d B5 wavelet packet denoising,so as to screen out the best effect of sym5 wavelet packet denoising method. This method is effective to overcome the effect of wavelet denoising is not good and the shortcoming of the signal distortion, scope of application is not limited in the low frequency range. And reduced the loss of information, at the same time in the denoising of SNR and RSME performance index is obviously enhanced compared with the wavelet denoising.