Patent ID: 7293959
Filing Date: 2007-11-13
Classification: F03D,F05B,Y02E

Abstract:
1. Wind turbine blade including adjustable lift-regulating means arranged on or at a surface of the wind turbine blade and extending in a longitudinal direction of the blade, and activating means by which the lift-regulating means can be adjusted and thus alter the aerodynamic properties of the blade, the lift-regulating means and the activating means being adapted and arranged such that by activation of the activating means, the lift can be reduced in a zone extending in the longitudinal direction of the blade from a first position adjacent a tip of the blade to a second position between the first position and a root of the blade and this second position being variable in the longitudinal direction of the blade by adjusting the activating means characterised in that the lift-regulating means are formed of at least one flexible flap arranged on or at the surface of the wind turbine blade having a fixed blade profile, the at least one flexible flap extending in the longitudinal direction of the blade and being adjustable by means of one or more activating means to allow the lift-altering setting of the flap to be changed gradually in the longitudinal direction of the flap in order to reduce the lift of the blade gradually in the zone between the first position and the variable second position.