Abstract: The power quality is affected by the wind power injection into an electric grid. The performance of the wind turbine and thereby power quality are determined on the basis of measurements and the norms followed according to the guideline specified in International Electro-technical Commission standard; IEC-61400. The measurements of power quality are the active power; reactive power; voltage sag; flicker; harmonics and electrical behavior of switching operations and these are measured according to national/international guidelines. Unified Power Flow Controller (UPFC) is used to control the power flow in the transmission systems by controlling the impedance; voltage magnitude and phase angle. This controller offers advantages in terms of static and dynamic operation of the power system. A Unified Power Flow Controller (UPFC) is an electrical device for providing fast-sensation on high-voltage electricity transmission networks. This paper clearly shows the power quality issues which are improved using the Unified Power Flow Controller (UPFC) ; the fault protection issues are also discussed. The STATCOM and SSSC control scheme for the grid connected wind energy generation system for mitigating power quality issues is simulated using MATLAB/SIMULINK environment; and a DFIG is also used to study the response of the system during grid disturbances.
Keywords: Power quality, Doubly Fed Induction Generator DFIG, Unified Power Flow Controller UPFC, Grid connected DFIG system, Matlab Simulink