Performance of UPQC for Power Quality improvement

This paper deals with a Unified Power Quality Conditioner (UPQC) for load balancing, power factor-correction, voltage regulation, voltage and current harmonics mitigation, mitigation of voltage sag, swell and voltage dip in a three-phase three-wire distribution system for different combinations of linear and non-linear loads. The unit template technique (UTT) is used to get the reference signals for series APF, whereas the control algorithm for shunt APF utilizes two closed loop PI controllers. The control algorithm for shunt APF is made flexible so that it can correct supply power factor, eliminate harmonics, provide load balancing and also improve the load terminal voltage at point of common coupling (PCC). MATLAB/Simulink based simulation results are presented, which support the functionality of the UPQC.