Mitigation of Flicker and Harmonics in Grid Connected DFIG for Power Quality Improvement

Abstract

This paper focuses on the mitigation of voltage harmonics and flicker of a grid connected doubly fed induction generator for wind energy conversion system.  The harmonics have been mitigated by an active series filter and flicker levels have been minimized by optimal control of wind turbine output reactive power. The effectiveness of the proposed mitigation strategies has been analyzed for various grid conditions and different wind speeds. The flicker levels and voltage harmonics have been successfully reduced as per prescribed standards. The proposed system thus ensures that voltage impurity is not passed on to the grid and high power quality is maintained. 

Keywords: Doubly Fed Induction Generator (DFIG), Wind Energy Conversion Systems (WECS), Power Quality (PQ), Active Series Filter (ASF), Pulse Width Modulation (PWM), Point of Common Coupling (PCC)