Circulating Current Suppression for a Direct AC-ACModular Multilevel Converter in YDY coupling

International audienceA control strategy to manage the circulating currentcontent in a Modular Multilevel Converter in direct AC-ACtopology is proposed in this article. The converter is connected inthree-phase YDY configuration which forms a closed delta pathfor free current circulation while keeping outsider waveforms withlow THD content. Circulating current correction becomesnecessary face to any kind of unbalance or even to small powertransition. Simulations results show multiple frequency content inwaveforms using a resonant corrector and performances againstsystem unbalances