Evaluation method of harmonic emission level under the influence of multivariate nonlinear customer interaction

Under the background of high power electronic rate in city grid, power system presents the characteristics of multiple nonlinear customers interaction, which aggravates the harmonic pollution. Besides, the fluctuation of background harmonics becomes more severe, and certain correlations exist among the harmonic emission properties of different harmonic sources. As a result, there will be new challenges in the quantification of harmonic responsibility. In this paper, a sparse component analysis-based method is proposed to solve this problem. Through sparse transformation of the source signals, the measured harmonic voltage and current signals will be clustered linearly. The slope of the clustering line can be used to calculate the harmonic impedance, and then the harmonic responsibility can be quantified. The proposed method can ensure a high calculation accuracy even when background harmonics fluctuate greatly and each harmonic source is no longer independent. The feasibility of the proposed method is verified by simulation analysis.