基于改进HHT的故障电流相位抗干扰提取

针对传统分析方法难以分析非线性非稳态电网实测信号的缺点,文章提出了一种基于希尔伯特–黄变换(Hilbert-Huang Transform,HHT)提取电流相位的方法.为应对经验模态分解(Empirical Mode Decomposition,EMD)在分解过程中普遍存在的模态混叠现象,该方法通过添加基于原电流信号相...

Anti Interference Extraction of Fault Current Phase Based on Improved Hilbert-Huang Transform

In view of the fact that traditional analysis method is hard to analyze the non-linear and non-stationary power grid signal,a method of extracting current phase based on Hilbert Huang transform(HHT)is proposed.In response to the ubiquitous mode mixing phenomenon of empirical modal decomposition(Empirical Mode Decomposition,EMD)during decomposition,this method decomposes the new current signal into a series of intrinsic mode functions(Intrinsic Mode Functions,IMF)through adding auxiliary signals based on the relevant parameters of the original current signal.If the mode mixing phenomenon is removed,the high-frequency signal will be filtered.If not,the new auxiliary signal will be iterated for analysis until the phenomenon is removed.The IMF component of the fundamental frequency signal with the mode mixing removed will be extracted,and the phase of the fundamental frequency signal can be obtained by Hilbert transform.Matlab is used to simulate the voltage sag,harmonic interference and other fault signals in the actual power grid,and the simulation results verify the effectiveness and accuracy of this method for phase extraction.