A new DC-side active filter for inverter power supplies compensates for unbalanced and nonlinear loads

A DC-side active filtering system for inverter power supplied is presented. The proposed system effectively nullifies the pulsating currents in the inverter input terminals as a result of unbalanced or nonlinear type loads. In the case of a three phase four wire inverter power supply the circulating zero sequence currents in the neutral are also nullified. The proposed system is fast in response, high in efficiency, and does not necessitate excess capacitive kVA required to supply highly unbalanced or nonlinear type loads. Analytical procedure, simulation, and experimental results illustrate the effectiveness of the proposed DC-side active filtering system.<>