Semi-active fuzzy control of edgewise vibrations in wind turbine blades under extreme wind

In this paper, a new semi-active fuzzy control strategy is proposed for controlling edgewise vibrations of wind turbine blades under extreme wind. The control forces are provided by magnetorheological (MR) dampers mounted inside blades and appropriately manipulated according to a prescribed fuzzy control law. The fuzzy control system produces the required voltage to be input to the damper so that a desirable damper force can be produced. The finite element model of wind turbine with MR dampers is formulated, which considers the blade-tower coupling. Aerodynamic loads corresponding to a combination of steady wind and the effect of turbulence are computed by applying the blade element momentum (BEM) theory. Furthermore, the influence of position and number of the controllers is taken into account. The results of numerical simulations show that the proposed semi-active fuzzy control system can be beneficial in reducing the vibrations of wind turbine blades under extreme wind.