Active Filtering of Supply Voltage with Series-Connected Voltage Source Converter

In this paper, a static series compensator for voltage sag mitigation is completed with a voltage active filtering function for further power quality improvement. The control system developed here performs isolation of voltage harmonics in several rotating coordinate systems. thus being able to cancel (or reduce) only selected harmonics, if desired. Moreover, it compensates for the effect of the convener output filter, which is frequency-dependent. Simulated results confirm the capability of the device to cancel symmetrical and unsymmetrical harmonics. Moreover, it is shown by using actual voltage sag recordings that the addition of the active filtering feature does not affect the speed of response during transients.