An integrated nine-switch power conditioner parallel with transformer for power quality enhancement

in this paper, a configuration with a dual-port power converter bridging two sides of the transformer is proposed for power quality enhancement in distribution systems. The proposed configuration employs a nine-switch power converter instead of the traditional back-to-back power converter with 12 switches. The high voltage side port works as a double resonance injection hybrid active power filter to enhance the injection ability of harmonic currents, while the low voltage side port works as a traditional shunt active filter, thus the harmonic and reactive currents to the transformer can be reduced while the stability of DC-link voltage is enhanced. The simulation shows the validity of the proposed configuration.