On the design of horizontal axis two-bladed hinged wind turbines

Hinged two-bladed wind turbines are not necessarily free of disturbing vibrations. The combination of elastic or built-in blade coning with blade flapping about a conventional teeter hinge produces periodic blade angular-velocity variations in the blade tip path plane with associated vibrations and dynamic loads.uFkefpaper discusses and evaluates various hinge configurations for two-bladed rotors and shows why the conventional teeter hinge leads to nonuniform blade angular velocity in the blade tip path plane. The solution to this problem adopted for two-bladed helicopter rotors, though complex, could be of interest for large wind turbines. A much simpler solution, calling for the suppression of blade flapping by passive blade cyclic pitch variation produced by a strong negative pitch-flap coupling, was found to be practical for upwind tail vane stabilized two-bladed wind turbines.