Abstract: For the resonance problem of multi-paralleled grid-tired inverters in PV systems, Firstly, a small-signal circuit model of single inverter including current control, voltage feed-forward and PWM harmonic characteristics is established, and is expanded into a small-signal model for multi-paralleled inverters. An equivalent method of two inverters and a simplified method of a similar excitation source are proposed. And then, on this basis, the basic resonance characteristics of multi-paralleled inverters are analyzed, and the conclusion of that resonance of multi-paralleled inverters is related to the synchronism of control and carrier wave. Finally, the proposed equivalent model and analysis of resonance characteristics are verified by experiments.