基于Hilbert-Huang变换和小波包能量谱的电压暂降源识别

针对电压暂降源识别问题,提出一种基于Hilbert-Huang变换（HHT）和小波包能量谱的电压暂降源识别方法。首先对电压暂降信号经过经验模态分解（EMD）,得到一个固有模态函数（IMF）集合,然后将各IMF进行n层小波包分解并计算其小波包能量谱,得到Hilbert-Huang（HH）谱图。通过比较突变点、幅值、谐波等特征量,对电压暂降源进行识别。实验结果表明,该方法简洁可靠、识别准确性高、实用性强。

Identification of Voltage Sags Source Based on Hilbert-Huang Transform and Wavelet Packet Energy Spectrum

For the identification of voltage sags source, a method based on HHT and wavelet packet energy spectrum is proposed. Firstly, signals of voltage sags are decomposed by EMD to get the IMFs, then each IMF is decomposed by n-layer wavelet packet to calculate it’s energy spectrum, and the HH spectrum is acquired by HT. The voltage sags source will be identified through comparing such characteristics as mutation point, amplitude, and harmonic. The final result of this simulation proves that the method is simple and reliable, with high recognition accuracy and practicability.