UPQC coordinated control strategy with circulating active power

Functions of UPQC (Unified Power Quality Conditioner) converters are relatively independent under traditional UPQC control. Its series converter usually is in standby state without full use while its parallel converter usually is in heavy load state. In this paper, a novel UPQC coordinated control strategy is proposed which uses series converter to share reactive power compensation function of parallel converter especially in the case of no grid-side power quality problems. The strategy fuses composite control strategy of series converter and reactive power allocation strategy of both converters besides improving corresponding power quality problems. Analysis, along with simulation and experimental results verifies the feasibility and effectiveness of the proposed control strategy.