This paper deals with the development of a nonlinear model of a horizontal variable speed wind turbine, the obtaining of an appropriate linear model and the design and analysis of a linear quadratic controller with disturbance estimation. The optimisation criteria will have to define an acceptable compromise between the limitations of the power level in the above rated wind speeds and the maintenance of the aerodynamic properties of the rotor at high solicitations exerted by the wind. The main control objective is to provide an amount of energy that will not exceed the nominal parameters of the generator and thus avoid overheating.