This paper studies the performance of a robust control approach which combines the Super-Twisting Sliding Mode Control with adaptive Takagi-Sugeno fuzzy logic systems in fractional order. The objective is to extract maximum power of a variable speed wind energy system equipped with permanent magnet synchronous generators. The developed nonlinear approach aims to reduce the chattering problem and improve system’s tracking and robustness despite external disturbances and parametric variations. The stability of the control laws is demonstrated by the stability analysis of Lyapunov theory. To validate the suggested approach, simulations using Matlab/Simulink for integer-order and fractional control schemes were conducted.