Development of Unified Power Quality Conditioner for Power Quality Improvement in Distribution System using SRF and P-Q Theory-Based Control Strategies

A Unified Power Quality Conditioner (UPQC) functions as an integrated compensation system capable of addressing both voltage-based and current-based power quality disturbances in electrical distribution networks. The device operates through coordinated action of two converters: a series-connected unit that corrects abnormalities in the supply voltage, such as waveform distortion and magnitude variations, and a shunt-connected unit that stabilizes the DC-link voltage while suppressing unwanted current components and reactive power demand. In this work, control of the series and shunt converters is achieved using synchronous reference frame techniques and instantaneous power–based control principles, respectively. The effectiveness of the proposed control framework is examined through detailed modeling and simulation of a three-phase distribution network implemented in MATLAB/Simulink. Simulation outcomes confirm the capability of the proposed approach to enhance overall power quality performance under different operating conditions.