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

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.Index Terms-Active power filter (APF), power angle control (PAC), power quality, reactive power compensation, unified power quality conditioner (UPQC), voltage sag and swell compensation.

Sinusoidal Current Control Strategy for UPQC in Grid Connected PV-Fuel Cell Microgrid

“…In the UPQC-DG, with storage, such as battery and flywheel storage, the shunt part of UPQC is in connection with the PCC, whereas the series part is positioned prior to the PCC in series with the grid. In case the storage is present, the DC link may be hooked up with it [2] …”

“…Lee et al [1] proposed a control strategy for UPQC-Q which offers minimum active power injection by which voltage sag can be compensated effectively and economically. Khadkikar et al [2] suggested the control method of series inverter of UPQC by using power angle control(PAC) series inverter can compensate both voltage sag/swell and load reactive power sharing between two inverters. As the model controls both active and reactive power flow the model named as UPQC-S. Khadem et al [3] proposes a new topology of UPQC i.e.…”

Voltage sag compensation strategy for unified power quality conditioner with simultaneous reactive power injection

“…Several researches mainly focus on capacity optimization of the UPQC [13][14][15][16]. However, the proposed strategy focuses on the limitation of current-carrying capability due to the following reasons.…”

“…Compared with [14], the demand of active power injection using UPQC-S strategy P inj ' can be given by…”

“…In addition, Ref. [14] proposed a voltage sag/swell compensation strategy with simultaneous active and reactive power injection by both converters of UPQC (UPQC-S), which can maximize the capacity utilization of series converter and compensate the load reactive power.…”