This paper presents modeling, analysis and control of a grid connected doubly fed induction generator (DFIG) wind turbine, during steady-state and transient operations. A mathematical model for different parts of the wind energy conversion system using DFIG has been examined using MATLAB/SIMULINK. A control structure using standard proportional integral (PI) controller and a voltage-oriented control strategy based on a rotating reference frame has been used. The machine model considers operating conditions below and above synchronous speed. The Maximum Power Point Tracking (MPPT) method has been presented also to improve efficiency and energy extraction in wind turbine systems. Characteristic power curve method has been used as one of the popular MPPT methods. In this paper, simulation results of the DFIG model have been presented. Then, DFIG model has been connected to the grid model and examined using PI controller under different conditions. The Internal Model Control (IMC) method has been used for tuning the PI controller. The proposed PI controller shows stable operation at different conditions.