This book entitled, "Improving Power Quality Using Unified Power Quality Conditioner Based on Multilevel Topology" has been written in a simple and lucid language for Electrical undergraduate, postgraduate and Ph.D. students of all engineering colleges. This book helps to enable the students in understanding the concept of power quality using UPQC. The book can serve as a reference for academic researchers, practicing engineers and other professionals.Power quality has been considered as the challenging task in the realization of a smart grid. The Active Power Filter (APFs) is capable of performing fast filtering and active compensation, so it was preferred to solve the problems occurred due to power quality issues. Moreover, it was aimed to solve load current related power quality constraints such as unbalanced power, huge Total Harmonic Distortion (THD) and reduced power factor. The Unified Power Quality Conditioner (UPQC) has effectively integrated with wind turbines for controlling the inappropriate supply of voltage and load current. The UPQC is a combination of shunt APF, series APF and the conventional DC link capacitor.