Wind energy is an important source of renewable energy which has a potentiality of generating energy on large scale. This emerging new technology becomes more demanding as variable speed wind turbines are highly efficient than the fixed ones. The study of variable speed wind generation system is done which is based on Doubly Fed Induction Generator (DFIG). The connection of the stator of the doubly fed Induction generator is done directly with the grid. But the connection of the rotor is done with a help of back-to-back converter which uses sinusoidal PWM technique for reducing harmonics that arise in the system. The connection of the wind energy conversion systems to the grid are done by Voltage Source Converters (VSC) so as to make variable speed operation possible. The protections of the system are also taken into consideration where the detection and isolation of the fault becomes a primary task. The paper deals with the application of DFIG, back-to-back converter control harmonic analysis under various fault conditions and finally the SIMULINK/MATLAB simulation of a model for a grid connected wind farm using Doubly Fed Induction Generator and their corresponding results and waveforms are obtained.

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Simulation Has Been Carried Out In Matlab/simulink Of 2010a(i. e. Matlab R2010a). The Results Show The Harmonic Analysis For Both No Fault And Response Under Faulty Conditions.