Power Quality Enhancement of DFIG Based Wind Energy System Using Priority Control Strategies

Abstract

The integration of intermittent renewable energy sources into the electric grid presents some challenges in terms of power quality issues, voltage regulation and stability. Power quality relates to those factors which affect the variability of the voltage level and distortion of the voltage and current waveforms which can cause severe adverse effects to the electric grid. The paper focuses on the design and evaluation of a priority control strategy for improving the quality of energy of a grid-connected variable speed Doubly Fed Induction Generator (DFIG) wind energy conversion system. The aim of priority control is to manage the priority among three different controls: active stator power control; reactive stator power control and harmonic rotor current control by using the active shunt filter with SRF method harmonic compensation, and to have a high performance and robustness; an adaptive-fuzzy PI control are including for currents rotor control. The simulation model was developed in Matlab/Simulink environment. The results show that the proposed control scheme can effectively reduce the Total Harmonic Distortion (THD) in the grid currents.