Composite Fuzzy and Current Reference based Peak Power Tracking for Micro Wind Turbine

Power characteristics of a wind turbine follows the hill-shape according to the speed of the wind supplied. Tracking maximum power point is more complex as compared to PV-MPPT techniques, the reason being high intermittence than solar power. The perturb and observe MPPT algorithm is applicable to wind turbines as well, the advantage of which is the lesser switching stress on the controlled semiconductor switch. The disadvantages of this conventional method include the delay to reach maximum power point as compared to the newly developing soft computing based tracking methods, which can have better peak seeking speed and better global search capabilities, but will cause higher switching stress on the switching device. This paper presents a composite control algorithm for wind energy conversion system, where fast behaviour of fuzzy-logic based control to achieve peak power point and lesser switching stress given by current reference based control, are combined to form one single system.