Research on impedance model of grid-connected inverter considering harmonic current
WANG Xilian
WANG Shun
CHENG Di
Abstract：The presence of harmonic interactions between inverter side and grid side,which a number of inverters are coupled to the grid,may affect the stability of distributed generation(DG) system.This paper deduces the impedance model of single-phase grid-connected inverter with LCL filter based on a dual-loop control scheme,and then analyzes the impedance model in the ease of considering the nonlinear factors.Based on analyzing low frequency characteristics of inverters,grid-eonnected inverter harmonic current is directly incorporated into the impedance mod el to make the impedance model more in line with actual circuit model,the harmonic impedance model is set up.Based on the proposed harmonic impedance model,the harmonic interactions of DG system is modeled and analyzed.Using the circuit model as a standard,the results of harmonic analysis using the harmonic impedance model are compared.The simulation results verify the high accuracy of the proposed model.
Keywords：grid-connected invertersharmonics interactionscurrent harmonicsimpedance modelnonlinear factorsresonance
Publication Date：2017-01-01
Online Publishing Date：2025-08-15(First online date of this platform, not the publication date of the document)
Pages：9( 90-97,105 )