A New Filter Topology for Multi-Paralleled Grid-Connected Inverters

The resonance frequency of the multi-paralleled grid-connected inverters with LCL filter may be affected by the parallel number due to the impact of the grid impedance, which may deteriorate the performance of the active damping methods aimed at fixed resonance frequency. In this paper, a new topology is proposed using common capacitors to acquire a fixed resonance frequency. Furthermore, a passive damping design is realized based on this topology which greatly reduces the number of damping devices compared with conventional passive damping strategy. Finally, simulations are performed to verify it.