Paper Title
Improvement Of Power Quality By Using Unified Power Quality Conditioner

The term power quality is most important aspect in any power delivery system. The main causes of poor power quality are supply voltage variations i.e. voltage sag/swell, harmonics in load current and poor power factor. In order to deal with this problem, UPQC is the most effective power device preferred to address the power quality problems. This paper deals with Unified Power Quality Conditioner (UPQC) which is the combination of series and shunt active power filter to compensate simultaneously load current harmonics, supply voltage fluctuations and to improve power factor. In other words, the UPQC has the capability of improving power quality at the point of common coupling in power distribution system. This paper presents, a simplified synchronous reference frame (SRF) or d-q theory based control method applied to series active filter and instantaneous reactive power or p-q theory based control techniques applied to shunt active filter to compensate power quality (PQ) problems by using UPQC. The performance of UPQC is evaluated by using MATLAB/SIMULINK software. Index Terms-Active power filter (APF), harmonics, power quality (PQ), synchronous reference frame (SRF), unified power quality conditioner (UPQC).