www.tjprc.org editor@tjprc.org International Journal of Electrical and Electronics Engineering Research (IJEEER) ISSN(P): 2250-155X; ISSN(E): 2278-943X Vol. 4, Issue 2, Apr 2014, 289-298 © TJPRC Pvt. Ltd. POWER QUALITY IMPROVEMENT OF GRID CONNECTED TO DFIG BY ACTIVE SHUNT FILTER SANJEEV KUMAR BHALLA 1 , SATNAM SINGH MATHARU 2 & R. K. JARIAL 3 1 School of Electronics & Electrical Engineering, Lovely Professional University, Phagwara, Punjab, India 2 Department of Electrical Engineering, CTIEMT, Jalandhar, Punjab, India 3 Department of Electrical Engineering, NIT, Hamirpur, Himachal Pradesh, India ABSTRACT Due to increased proliferation of Non Linear Devices in the networks, the Power Quality of the Grid deteriorates. With increasing dependence on Wind Power as a renewable source of energy by the utilities, a large no. of DFIGs are connected to the Grid. The Non Linear Loads draw a significant amount of Harmonic Current which in turn generates Voltage Harmonics also in the Grid on account of Grid impedance. The present paper focuses on mitigation of the Harmonics generated by a Non Linear Load using Active Shunt Filter. This ensures that the DFIGs connected to the Grid are safeguarded from the detrimental effects of Harmonics, thus enabling them to maintain the Power Quality Standards. As shown in the simulation results, the proposed model developed in PSCAD/EMTDC is capable of suppressing the Current Harmonics substantially from very high to low levels which are acceptable as per prescribed standards. The proposed system thus ensures that the current impurity is not passed on to the grid and high power quality is maintained. KEYWORDS: Doubly Fed Induction Generator (DFIG), Power Quality (PQ), Active Shunt Filter (ASF), Wind Turbine (WT), Total Harmonic Distortion (THD) 1. INTRODUCTION The increasing proliferation of Non Linear Loads in the network is resulting in PQ issues such as Flicker, Harmonics, and Voltage Sags & Swells. Poor PQ results in many problems like reduced life of Equipment, deteriorated system performance, mal functioning of control equipments and protection devices. The PQ issues have gained more significance off late on account of development of highly sensitive equipments, interconnection of large networks and increasing awareness of consumers towards PQ. DFIGs connected to the grid are generally located at remote locations. The Harmonics generated on account of Non Linear Loads can travel to the DFIG through Long Transmission Lines and can largely compound the PQ problems of DFIG which is expected to meet the PQ standards for various wind speeds and turbulence. A technique for Harmonic Compensation by using an Active Filter connected in series to a passive filter that leads to a practical and economic solution has been earlier proposed [1]. Uses and advantages of applying Active Power Filters to compensate Power Distribution System has been presented in [2]. In [3], a comprehensive review of active filter configurations, control strategies, selection of components and other related economic and technical considerations and their selections for specific applications has been summarized.