Wind Energy Conversion System Integratedwith Grid under Variable Speed Scenario

The recent sensitive issue of climate change is due to the extensive amount of carbon emission through the consumption of fossil fuel as the primary option for energy demand. Due to the negative impact of green house effect, the alternative and renewable energy options have received significant attention global scale. The two branched approach of renewable energy projects including the reduction in the global greenhouse gas emissions and encouragement to the development of alternate green energy options like wind energy. Wind energy has become one of most acceptable solution among the different renewable energy resources because of the application of power electronic based controllers that allows the wind energy conversion system (WECS) to generate quality electric power irrespective of variable wind profile. The continuous flow of quality power from WECS to grid is insured for wider range of wind speed. Doubly fed induction generator (DFIG) used in WECS having power electronic converter which requires very small friction of power in comparison to the total generation capacity. This paper brings out the analysis of a DFIG system in terms of its stator and rotor currents and real and reactive power balance when the machine is operating with varying wind velocity conditions. Various possible maximum power point tracking techniques are listed in the paper. The suitable Maximum power point tracking (MPPT) technique has also been suggested to harness maximum available power for a given wind velocity to ensure the continuous power flow from WECS to the power grid.