Modeling a DFIG-Based Wind Turbine Focusing on DFIG and Aerodynamic Models

Abstract

The present study is an attempt to develop and implement mathematical models of variable speed wind turbines using Doubly-Fed Induction Generator (DFIG) including aerodynamic model and DFIG through newly developed Matlab/Simulink .The so called models are developed in order to investigate dynamic behavior of power networks as well as to design and evaluate the behavior of each wind turbine under normal and disturbance conditions. In the study, aerodynamic (rotor) model is based on torque coefficient Cq look up table which is according to BEM method. DFIG model is developed in two sub models including generator and power converters. In generator model, electrical dynamic equations of wound rotor induction generator are provided in two different models (fifth-order model and third-order model) by choosing synchronous rotating reference frame.  As the simulation result revealed, the stator power is limited at rated value at high wind speed but wind turbine is operated at optimum power efficiency at lower wind speed to gain optimal power output, indicating a good agreement with the real behavior of the system.