Abstract：To meet the power system′s needs of realtime,fast tracking and detecting of harmonic currents with an active power filter(APF),a novel method of detecting the power system harmonic currents based on ensemble empirical mode decomposition(EEMD) was proposed. The current signal was decomposed in terms of intrinsic mode functions(IMF).The Gaussian white noise was adopted in sifting process,in order to provide a uniform reference frame in the time space.End effect process strategy was adopted to solve the mode mixing problem. A current tracking detector was designed based on this algorithm and the simulation was carried out. The results show that the method can eliminate the mode mixing in the sifting process,the hardware is simpler,and the error between the detected and the expected amplitudes of fundamental component is only 108％. The algorithm can separate the current signal into fundamental component and harmonic components accurately,and the delaytime of nonstationary signals tracked and detected by the algorithm is only 6 μs. The realtime harmonic analysis of the algorithm is superior to the traditional, thus the method can be applied to current tracking control circuits of APF and other harmonic currents detectors.
2010, Vol. 31 
