The Analysis of inverter output impedance and its influence on circulating power for inverters paralleling

Basing on the analysis of inverter model and its corresponding control system, this paper gives the expression of inverter equivalent output impedance, which is not only related with the main-circuit parameters, but also related with the controller parameters. Then the simulation results of two paralleled inverters under different controller parameters are given to prove the validity of the inverter equivalent output impedance.