Harmonic Modeling of Nonlinear Home Loads Based on Z-transform Parameter Estimation Method

Abstract

To accurately analyze the harmonic characteristics of nonlinear home loads with single-phase uncontrolled rectifier bridge circuit, a harmonic coupled model in the frequency domain is established based on the Z transform parameter estimation method. Firstly, the detailed frequency domain harmonic coupled model of a single-phase uncontrolled rectifier bridge with the resistance and inductance on AC side is derived and established, which can accurately reflect the coupling relationship between harmonic voltages and harmonic currents. Then a parameter estimation method based on the Z-transform method is proposed to estimate the circuit parameters of the nonlinear home load quickly and effectively, which provides accurate circuit parameters for the harmonic coupled model. Finally, under typical voltage conditions, the effectiveness and accuracy of the harmonic coupled model and parameter estimation method are verified by simulation and experiment.