Hilbert-Huang变换方法在谐波和电压闪变检测中的应用

将一种新的非平稳信号处理方法,即HHT(HilbertHuang Transform)方法用于检测与时频分析典型的电能质量扰动信号,如谐波、电压闪变与波动信号.该方法由经验模态分解法(EMD)及Hilbert变换两部分组成,先用EMD提取信号的固有模态函数(IMF)分量,再对IMF作Hilbert变换求瞬时频率和幅值.该方法可以从时域和频域两方面同时对信号进行分析,能够准确检测出突变、非平稳谐波和电压闪变信号的时间、频率和幅值信息.仿真分析结果表明了该方法检测非平稳电能质量扰动信号的有效性.

APPLICATION OF HILBERT-HUANG TRANSFORM METHOD IN DETECTION OF HARMONIC AND VOLTAGE FLICKER

The authors apply a novel non-stationary signal processing method, i.e., the Hilbert-Huang Transform (HHT) method that is composed by empirical mode decomposition (EMD) and Hilbert transform, to the detection and time-domain analysis of typical power quality disturbance signals, e.g., harmonics, voltage flicker and fluctuation. At first this method extracts the intrinsic mode function (IMF) component of the signals, then the Hilbert transform is applied to IMF to obtain the instantaneous frequency and amplitude. With this method the disturbance signal can be simultaneously analyzed in both time-domain and frequency-domain, and the time, frequency and amplitude information of non-stationary harmonics and voltage flicker signals can be accurately detected. Simulation results show that this method is effective in the detection of non-stationary power quality disturbance signals.