Enhanced Power Quality through D-Q Theory-Based Three-Phase Unified Power Flow Controller

Abstract This paper presents an innovative approach to improve and power quality enhancing by utilizing a Unified Power Flow Controller (UPFC) in voltage control mode. The reference stator current is derived using the D-Q theory, leading to a substantial reduction in the Total Harmonic Distortion (THD) of the source current. By maintaining a unity power factor (UPF) at the load terminal during normal operating conditions, this method surpasses traditional voltage-controlled UPFCs. The controller effectively manages reactive power and alleviates voltage sag issues in distribution networks. The system’s performance is comprehensively evaluated through MATLAB simulations, highlighting its capacity to improve energy efficiency and system reliability.