Wind energy is the most preferable renewable energy for the generation of electric power. Initially the fixed speed wind turbines were used for the generation of power, but now a day the variable speed wind turbines has become popular because of its advantages over fixed speed wind turbines. DFIG which is a variable speed wind turbine, has been used widely because of its low cost, higher energy output, and independent control of real and reactive power. However the DFIG wind turbines are facing

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... the problems of power fluctuation during normal operation in the system and this leads to Low Voltage Ride Through [LVRT] during the fault occurrence. At the initial stages, WTG's are allowed to disconnect from the grid during fault. But due to increasing trend in WTG's, it is necessary for the wind turbine to be connected with the grid, even when fault occurs in the system. According to the Grid code requirements the wind farms should contribute to power system control like frequency and voltage and make the wind turbine to be connected to grid and support it by injecting the reactive power to the grid. This can be achieved by using hardware or software implementation for the rotor side and grid side converter, so that it can prevent the converter from tripping and provide uninterruptible operation to the DFIG when severe fault occurs. The different LVRT control strategies have been analyzed in this paper.