Aerodynamic braking system analysis of horizontal axis wind turbine using slotted airfoil

Abstract Wind turbines are becoming an increasingly popular solution to generate clean and sustainable energy. The wind turbines are designed to generate power at a rated wind velocity. When the wind turbines are exposed to higher wind velocities such as storm or hurricane, the wind turbine rotor rotates at an extreme speed that damages the wind turbine blade and affects the structural stability of the entire system. The various mechanical braking system and Aerodynamic braking systems are presently used to control the over speeding of the wind turbine at extreme wind velocity. In this newer approach, it is attempted to control the over speeding of the wind turbine aerodynamically by providing the chord wise slot (opening). The turbine blade with chord wise slot alters the pressure distribution over the turbine blade that brings down the rotational speed of the wind turbine within the allowable limit. In this approach, the over speeding of the wind turbine rotor is effectively controlled without affecting the power generation. In this paper the different parameters of the chord wise slot such as position and length of the slot, impact on power generation are analysed and the slot parameters are experimentally and computationally optimized.