A review of UPQC topologies for reduced DC link voltage with MATLAB simulation models

The Unified Power Quality Conditioner (UPQC) is distribution FACTS device which is combination of Shunt compensator (DSTATCOM) and series compensator (DVR) connected back to back by a common DC link capacitor. The DC link capacitor generally as per requirement of shunt compensation which is 1.6 V of line voltage of system, and for series VSI it is equal to system line voltage, the mismatch of shunt and series DC link voltages the system has to design for higher value of DC link voltage as per shunt compensation, which causes over rating of series VSI switches, so In this paper a review on topologies of the UPQC for reduced dc link voltage has been presented to improve the electric power quality with less Voltage source inverter rating at distribution levels. The advantages and drawbacks are discussed for three phase three wire UPQC and three phase four wire UPQC reduced dc link topologies. A simulation study has done for comparison of neutral clamped topology with series capacitor connection for shunt active filter topology for reduction of DC link voltage and reduction of THD and switching by using MATLAB Simulink software. Simulation results and MATLAB designing circuit presented for these two topologies.