An adaptive transient tracking harmonic detection method for power quality improvement

Among various power quality issues, presence of harmonics in voltage/current waveforms is a major one. It becomes prominent in smart grids, where renewable energy sources are integrated through power electronic interfaces. Efficiency of harmonic mitigation techniques depends on accurate estimation of fundamental and non-fundamental parts of the waveform. In this paper, an adaptive harmonic estimation technique based on empirical wavelet transform is proposed. This technique is applied to source current waveform measured from a sample power system with nonlinear load. During transients, the algorithm is found to be capable of tracking the change in the fundamental frequency with good time-frequency localization. Simulation of the algorithm is carried out in MATLAB/Simulink. Results are presented and discussed.