This paper proposes the modelling and control of Wind Energy Conversion Systems (WECS) based on Doubly Fed Induction Generator (DFIG). The fuzzy logic control is used to improve the extracted wind power. At given wind velocity, the mechanical power available from a wind turbine is a function of its shafts speed. Then, the rotor side converter (RSC) is controlled in the aim to follow the optimal torque for given maximal wind power. A new maximum power point tracking (MPPT) strategy based on the fuzzy logic controller was developed. Moreover, a new approach to estimate the speed from the measurement of the power is presented. The effectiveness of the proposed control strategies is validated by theoretical analysis and simulation carried out in Matlab/Simulink environment.