Four-branches-inverter-based-active-filter for unbalanced 3-phase 4-wires electrical distribution systems

This paper deals with the design, analysis, and digital simulation of a four-branches-inverter-based-active-filter, that compensates the reactive power and eliminates the harmonic currents in the phases and neutral of an unbalanced 3-phase 4-wires electrical distribution system, feeding nonlinear loads. The active filter uses a 4-branches-DC/AC-inverter as the power stage. As in a typical active filter, 3-branches are needed to compensate the three-phase currents and one-branch compensates the neutral current. Simulation results are shown to prove the active filter performance under different configurations.