Pitch Control of DFIG based Wind EnergyConversion System for Maximum Power PointTracking

With the advancements in the variable speed system design and control of wind energy systems, the efficiency and energy capture of these systems is also increasing. Intelligent control techniques can play a vital role in improving the performance and the efficiency of Wind Energy Conversion Systems (WECS). This paper proposes the Pitch control of a Doubly Fed Induction Generator based wind energy system with the aim of maximizing the power output by using fuzzy controller along with Hill Climbing Search (HCS) algorithm. Pitch control is the most common means for regulating the aerodynamic torque of the wind turbine and this algorithm searches for the peak power by varying the speed in the desired direction. The generator is operated in the speed control mode with its reference speed being varied in accordance with the magnitude and direction of change of active power. The peak power points in the Power (P)-Speed (ω) curve correspond to dP/dω=0. This fact is made use of in the optimum point search algorithm. The proposed method is computationally efficient and can be easily implemented in real-time. This system is modeled using MATLAB/Simulink. Simulation results prove the efficiency of this technique.