Three-phase reactive power compensation using a single-phase AC/AC converter

A new control strategy and topology for VAr compensation is presented and analyzed. It treats a three-phase power system as two energy ports and uses one single-phase bidirectional AC/AC power converter to transfer reactive energy between the two ports to produce three-phase reactive power. The compensated reactive power can be leading or lagging. Hysteresis control is investigated as a means of current modulation. The system has fast transient response capability, and one unit of AC/AC converter power generates 2.412 units of reactive power. The characteristics of the topology and predicted results are verified experimentally.