Fault Tolerance and Power Quality Study of Dfig Based Wind Turbine System

Wind power is the fastest growing renewable source of electrical energy hence it has become necessary to address problems associated with maintaining a stable electric power system. The wind generated power is always fluctuating due to its time varying nature and causing stability problem. 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. The measurement and assessment of power quality characteristics of grid connected wind turbines are specified in International Electro-technical Commission standard IEC61400-Part 21. Another effort is given in this report to make a comparative study of the fault current and voltages of a DFIG (Doubly Fed Induction Generator) system with using a relay protection system and incorporating UPFC in the system. The UPFC 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.