A novel passive damping LCL-filter for active power filter

This paper proposed a novel parallel passive damping topology for LCL-filter, which consists of damping resistors paralleled with grid side inductor and damping inductors connected in series with filter capacitance. The proposed filter could improve the harmonic attenuation with lower losses. Damping losses and harmonic suppressions of different filtering topologies were presented and it was found that the proposed topology was more effective than the traditional parallel passive damping LCL-filter or the parallel passive damping LLCL-filter. A design procedure for the filter was also shown in this paper. Finally, a MATLAB model was built to verify the design.