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Recently, doubly fed induction generator (DFIG) and synchronous generator are mostly applied for wind power generation due to high efficiently for wind energy capture. An inverter system is required to control wind turbine speed and power factor in those generators. The inverter rating of the synchronous generator equals to generator rating. However, DFIG has the advantage that the inverter rating is about 25% to the generator rating. The paper describes a vector control of DFIG inter-connected to power line.To enable independent control of the stator active power P 1 and the stator reactive power Q 1 of the DFIG, a vector control is used. The active power is determined by the rotor q-axis current and the reactive power is determined by the rotor d-axis current. By the control of those currents, the wind turbine speed and the power factor are controlled independently. A wind turbine speed varies according to the active power. Thus, the speed is controlled by the rotor q-axis current and the power factor is controlled by the rotor d-axis current. The rotor d-axis voltage and q-axis voltage are expressed by the generator parameters and slip of DFIG, power system voltage, the rotor d-axis current and the q-axis current. A voltage source inverter connected on the rotor winding carries out the control of the active power and the reactive power.The performance of proposed vector control is examined using power system simulation software PSCAD/EMTDC for the DFIG inter-connected to 6.6 kV distribution line. The system configuration of wind power generation is shown in Fig. 1. The DFIG parameters are shown in Table 1. Simulation result for step response to the stator active power reference value and turbine output is shown in Fig. 2. Also, it for step response to the stator reactive power reference value is shown in Fig. 3. The detailed simulation results by PSCAD/EMTDC show good dynamic responses and high accuracy to the stator active power control and the stator reactive power control.