一种基于小波包变换和有效值算法

近年来，随着科技的迅猛发展，各种敏感电力电子设备在工业中的应用越来越广泛，使得电压暂降与中断已上升为最严重的电能质量问题。对电压暂降扰动发生、恢复时刻和暂降幅值的检测是电压暂降补偿首先要解决的问题。在对现有的电压暂降检测方法进行仔细的研究和比较后，提出一种将小波包变换和有效值算法相结合的电压暂降检测方法，利用这种方法可以更加准确、简洁地检测出电压暂降扰动。利用小波包变换理论实现了电压暂降的精确定位和消噪处理，其消噪效果优于小波变换；利用有效值算法快速、直观地实现了电压暂降幅值的检测。仿真结果验证了该方法的有效性。

A Detection Method of Voltage Sag Using Wavelet Packet Transform and Rms Algorithm

In recent years, with the fast development of science and technology, the application of sensitive electrical appliances in industry is more and more wide, which make the voltage sag and interruption become the most important problem of power quality. The detection of time, duration and amplitude of voltage sag is the primary problem for voltage sag compensation. This paper proposes a new detection method of voltage sag combining wavelet packet transform and rms algorithm on the basis of deep and careful study of present voltage sag detection method. This method can detect the voltage sag more precisely and simply. In this paper, precise location and de-noising of voltage sag is reached by using the principle of wavelet packet transform, the effect of which is superior to wavelet transform; and the rapid and intuitional detection of voltage sag amplitude is realized by using rms algorithm. The results of simulation verify the validity of this method.