Document Type : Research Paper


1 1- Electrical Engineering Department, Collage of Engineering, University of Basrah, Basrah, Iraq 2- Ministry of Industry and Minerals, SDI, Mosul, Iraq

2 Electrical Engineering Department, Collage of Engineering, University of Basrah, Basrah, Iraq

3 Electrical Engineering Department, Collage of Engineering, University of Mosul, Mosul, Iraq


The power quality (PQ) is a major issue for both electrical utilities and their customers. The nonlinear loads cause PQ problems like current harmonics, voltage harmonics, frequency deviation, voltage sag and voltage swell. A unified power quality conditioner (UPQC) is utilized in this research to minimize these PQ problems. The UPQC is made up of two active power filters (APFs), one of which is connected to the line in series and the other in parallel. The Unit Vector Template Generation (UVTG) approach is used to control the series APF, whereas the Synchronous Reference Frame (SRF) technique is used to control the shunt APF. The compensating properties of a series-shunt APFs when the loads become imbalanced have been explored. The system performance has been tested under conditions current harmonics, voltage harmonics, voltage sag, and voltage swell. The voltage harmonics are identified and reparation in a series APF using the UVTG technique, whereas the harmonics and unbalanced currents are identified and reparation in a shunt APF using the SRF method. An IEEE-519-compliant THD (Total Harmonic Distortion) of less than 5% is achieved by UPQC in simulations with unbalanced loads. The findings indicate that harmonic currents and supply voltage fluctuations were lessened by UPQC.


Main Subjects

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