:The purpose of this work is to develop a maximum power tracking control strategy forvariable
speed wind turbine systems. Modern windturbine control systems are slow, and they depend on the design
parameters of the turbine and use wind and / or rotor speed measurements as control variable inputs. The
dependence on the accuracy of the measurement devices makes the controller less reliable. The proposed
control scheme is based on the stiff system concept and provides a fastresponse and a dynamic solution to
the complicated aero dynamic system. This control scheme provides a response to the wind changes with
out the knowledge of wind speed and turbine parameters.
The system consists of a permanent magnetsynchronous machine (PMSM), a passive rectifier, adc/dcboost
converter, acurrent controlled voltages our ceinverter, and a micro controller that commands the
dc/dcconverter to control the generator for maximum power extraction. The microcontroller will also be able
to control the current output of the three-phaseinverter. In this work, the aerodynamic characteristics of
wind turbines and the power conversion system topology are explained. The maximum power tracking
control algorithm with avariable stepestimat or is introduced and the modeling and simulation of the wind
turbine generator system using the MATLAB/SIMULINK® software is presented and its results show, at
least in principle, that the maximum power tracking algorithm developed is suitable for wind turbine
generation systems.