In this paper, the implementation of a shunt active power filter with a small series reactor for a three-phase
system is presented. The system consists of computer loads, which are harmonic voltage sources, with
significant unbalanced components. The filter consists of a three-phase current-controlled voltage source inverter
(CC-VSI) with a filter inductance at the AC output and a DC-bus capacitor. The CC-VSI is operated to directly
control the AC grid current to be sinusoidal and in phase with the grid voltage. The simulation results indicate
that the filter along with the series reactor is able to handle the harmonic voltage sources, as well as the
unbalance, so that the grid currents are sinusoidal, in phase with the grid voltages and symmetrical.