International Journal of Engineering Works ISSN-p: 2521-2419 ISSN-e: 2409-2770 Vol. 7, Issue 01, PP. 01-09, January 2020 https://www.ijew.io/ https://doi.org/10.34259/ijew.20.7010109 © Authors retain all copyrights 2020 IJEW. This is an open access article distributed under the CC-BY License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. Application of Unified Power Quality Conditioner in Grid Integration of Solar PV System Niaz Ali 1 , Prof. Dr. Muhammad Naeem Arbab 2 , Rizwan Kamal 3 , Muhammad Bilal 4 1,2,3,4 US Pakistan Center for Advanced Studies in Energy, University of Engineering and Technology, Peshawar engr.niazi91@yahoo.com 1 , mnarbab@yahoo.com 2 , rkrizwan891@gmail.com 3 , engr.bilal92@gmail.com 4 Received: 14 December, Revised: 20 December, Accepted: 27 December Abstract—Modern power electronics has developed a great interest in grid integration of solar photovoltaics. The penetration of renewable energy resources causes problems of power quality, due to their intermittent behavior. These problems include but are not limited to reactive power flow, voltage dip or sag, over-voltage, distortions in current and voltage waveforms. Similarly, non-linear loads have been consistently increased on the consumer side. These power electronics-based equipment bring harmonics into the power system and as result demand of reactive power rises. This research aims a Unified Power Quality Conditioner for grid integration of solar PV. In the proposed technique, a part of the PV power is used for the power quality management and the rest of the power is sent back into the grid. The major constituents of PV system are; DC-DC boost converter, PV array, whereas, P &O algorithm is adopted to ensure the maximum power point operation of the PV array. The analysis and testing of the proposed approach have been successfully accomplished in MATLAB/Simulink. The results of the simulation reveal that along with the active power injection to the grid, the conditioner is capable to; pay compensation for harmonics, corrects sags and swells in voltage and also regulates the load voltage at its nominal value. Keywords— Solar PV, Unified Power Quality Conditioner, Power Quality, Grid Integration. I. INTRODUCTION The demand for electric power in several developing countries, specifically in Pakistan, is growing gradually. Due to environmental and economic concerns, renewable energy resources have been emerging widely in order to meet this demand, among these resources, sunlight is the most abundant one. Useful electrical energy can be achieved from the luminous energy of the sun by making use of solar photovoltaic. The major advantages and characteristics of a solar photovoltaic system are: environment friendly energy without the emission of greenhouse gases, long-lasting operation, installation is effortless, operational cost is negligible, no moving or rotating components are entailed in generating power, and most importantly, the PV system is much cheaper than other renewable resources such as wind energy system and hydropower system. Middle class people cannot only recover some money as far as their electricity bills are concerned but can vend the excess power to the utility by supplying it back to the grid. With the advances in modern power electronics, non-linear loads have been strongly grown on the distribution network. Moreover, the injection of a huge amount of harmonics in the electrical system can increase the system reactive power demand and hence, degrade the power quality. This low power quality can damage the equipment on the consumer side. This research gives energy consumers an opportunity to contribute in power generation and sell it. Thus, the system suggested in this work can contribute towards Pakistan’s power sector by making use of solar energy for refining the power quality as well as active power injection to the grid. This paper is structured as Section II provides an overview about the background of the research, Section III presents a general description of the proposed system, Section IV describes the system in detail, whereas, Section V analyzes the process of simulation and presents an overview of the results, and the last section i.e. Section VI portrays the conclusion of this research article. II. BACKGROUND Grid penetration of solar energy has been emerging since the development of modern power electronics [1]. However, integrating solar PV with grid is not a simple job because it may give rise to problems of power quality [2]. Power quality has become the principal concern for the realization of a smart grid [3]. Renewable energy resources such as wind and Solar PV behave intermittently. As far as weak distribution systems are concerned this behavior leads to power quality problems [4]. Few of the power quality issues, that may rise as a result of entrance of solar energy in the power network, are distortions in current and voltage waveforms, over-voltage (voltage swell) and voltage dip (sag), reactive power flow [3]-[9]. Such disturbances in voltage may also often initiate erroneous tripping and may damage the switching equipment. Capacitor banks heat up as a result of these disturbances [7], [10]. Likewise, non-linear loads are considerably growing on the consumer side. such a wide range