Research on non-isolated transformer single-phase UPQC system

The UPQC combines the functions of a voltage compensator and a current compensator to regulate power quality. This paper adopts a Novel Single non-isolation transformer Unified Power Quality Conditioner1 topology and introduces the novel single-phase Unified Power Quality Conditioner circuit topology and basic working principle. analyzes the Circulating Current problems of the novel single-phase Unified Power Quality Conditioner that exist in the system, for the circulation issues proposed a circulation suppression measures based on carrier modulation. Finally, experimental results based on a laboratory prototype are provided to verify the effectiveness of the control scheme.