UPQC-S: A Novel Concept of Simultaneous Voltage Sag/Swell and Load Reactive Power Compensations Utilizing Series Inverter of UPQC

TLDR

The study proposes the UPQC‑S concept, extending the PAC approach to enable simultaneous voltage sag/swell compensation and load reactive‑power sharing in a unified power quality conditioner. This is achieved by controlling the UPQC’s series inverter to deliver both active and reactive power, coordinating with the shunt inverter via active‑power control and PAC theory, and validated through MATLAB/SIMULINK simulations and DSP‑based experiments.

Abstract

This paper introduces a new concept of optimal utilization of a unified power quality conditioner (UPQC). The series inverter of UPQC is controlled to perform simultaneous 1) voltage sag/swell compensation and 2) load reactive power sharing with the shunt inverter. The active power control approach is used to compensate voltage sag/swell and is integrated with theory of power angle control (PAC) of UPQC to coordinate the load reactive power between the two inverters. Since the series inverter simultaneously delivers active and reactive powers, this concept is named as UPQC-S (S for complex power). A detailed mathematical analysis, to extend the PAC approach for UPQC-S, is presented in this paper. MATLAB/SIMULINK-based simulation results are discussed to support the developed concept. Finally, the proposed concept is validated with a digital signal processor-based experimental study.