Speed Control of a Wind Turbine Using Fuzzy Logic

Wind turbine generators are highly desirable to operate autonomously throughout the wind speed range below hurricane conditions. A key requirement to achieve this goal is to be able to control the wind turbine speed using a full-scope feedback control scheme. Currently, wind turbine speed is controlled by modulating the angular position of the rotor blades to catch the required amount of kinetic energy of the wind to produce the desired rotational speed. Typically, conventional PI controllers modulate the blades angular position only for wind speeds in the range from 12 m/s through 25 m/s. This paper introduces a fuzzy speed controller to control autonomously the turbine rotational speed in the whole wind speed range from 0 m/s throughout 30 m/s. After presenting several key concepts about small-scale wind turbines, the design of the fuzzy speed controller based on a TSK fuzzy system is introduced. In this regard, the proposed fuzzy speed controller intelligently extends the scope of control below nominal speed and above trip conditions.