Morphing segmented wind turbine and related method

Abstract

A downwind morphing rotor that exhibits bending loads that will be reduced by aligning the rotor blades with the composite forces. This reduces the net loads on the blades which therefore allow for a reduced blade mass for a given maximum stress. The downwind morphing varies the amount of downstream deflection as a function of wind speed, where the rotor blades are generally fully-aligned to non-azimuthal forces for wind speeds between rated and cut-out conditions, while only the outer segments of the blades are generally aligned between cut-in and rated wind speeds. This alignment for large (MW-scale) rated turbines results in much larger downstream deflections of the blades at high wind speeds as compared to that of a conventional rigid single-piece upwind turbine blade. Also provided is a pre-aligned configuration rotor whereby the rotor geometry and orientation does not change with wind speed, and instead is fixed at a constant downwind deflection consistent with alignment at or near the rated wind speed conditions. Also provided is a twist morphing rotor where the airfoil-shapes around the spars twist relative to the wind due to aerodynamic forces so as to unload the rotors when there is a gust. This can help reduce unsteady stresses on the blade and therefore may allow for reduced blade mass and cost. The twist morphing rotor may be combined with either downwind morphing rotor or pre-alignment rotor.

1 - 5 . (canceled) 
     
     
         6 . At least one individual blade segment for a wind turbine that is formed from a plurality of said individual blade segments whereby said individual blade segments comprise an internal passage extending longitudinally from a first end to a second end of each of said blade segments; wherein a plurality of spar members extend longitudinally through said internal passages of each of said blade segments such that said plurality of said spar members are aligned and in communication end-to-end through said internal passages and said plurality of blade segments are aligned and in communication said aligned spar members and define a complete rotor blade from a root that connects to a rotor hub to a blade tip of said rotor blade; a tension member extends longitudinally through said aligned spar members; and wherein said aligned spar members are configured to at least partially unwind due to centrifugal forces exerted on said blade segments and aligned spar members, said unwound spar members causing said blade segments to twist and provide twist morphing relative to said spar members. 
     
     
         7 . A rotor blade for a wind turbine, said blade comprising:
 a plurality of blade segments for use as part of a rotor;   each of said plurality of blade segments comprising an internal passage extending longitudinally from a first end to a second end of each of said blade segments;   a plurality of spar members extending longitudinally through said internal passages of each of said blade segments such that said plurality of said spar members are aligned and in communication end-to-end through said internal passages and said plurality of blade segments are aligned and in communication with said aligned spar members and define a complete rotor blade from a root that connects to a rotor hub to a blade tip of said rotor blade; and   said aligned spar members and blade segments are configured to pivot due to centrifugal forces exerted on said blade segments and aligned spar members, said pivoted spar members and blade segments causing said blade segments to provide a curvature defining a deflection angle relative to the axis of rotation plane of said rotor blade.   
     
     
         8 . The rotor blade of  claim 7 , wherein said pivoting is provided by at least one of the following: trunnion, hinge, pin joint, ball joint, flex joint, cable joint, or pivot device. 
     
     
         9 . The rotor blade of  claim 7 , wherein said downwind morphing of said spar members and blade segments are configured to adjust to prevailing wind. 
     
     
         10 . A method of manufacturing a rotor blade for a wind turbine, said method comprising:
 providing a plurality of blade segments for use as part of a rotor;   each of said plurality of blade segments comprising an internal passage extending longitudinally from a first end to a second end of each of said blade segments;   providing a plurality of spar members extending longitudinally through said internal passages of each of said blade segments such that said plurality of said spar members are aligned and in communication end-to-end through said internal passages and said plurality of blade segments are aligned and in communication said aligned spar members and define a complete rotor blade from a root that connects to a rotor hub to a blade tip of said rotor blade; and   said aligned spar members and blade segments are configured to pivot due to centrifugal forces exerted on said blade segments and aligned spar members, said pivoted spar members and blade segments causing said blade segments to provide a curvature defining a deflection angle relative to the axis of rotation plane of said rotor blade.   
     
     
         11 . A rotor blade kit for forming rotor blade on a wind turbine, said kit comprising:
 a plurality of blade segments for use as part of a rotor;   each of said plurality of blade segments comprising an internal passage extending longitudinally from a first end to a second end of each of said blade segments;   a plurality of spar members for extending longitudinally through said internal passages of each of said blade segments such that said plurality of said spar members are aligned and in communication end-to-end through said internal passages and said plurality of blade segments are aligned and in communication said aligned spar members and define a complete rotor blade from a root that connects to a rotor hub to a blade tip of said rotor blade; and   said aligned spar members and blade segments are configured to pivot due to centrifugal forces exerted on said blade segments and aligned spar members, said pivoted spar members and blade segments causing said blade segments to provide a curvature defining a deflection angle relative to the axis of rotation plane of said rotor blade.   
     
     
         12 . An individual blade segment for a wind turbine that is formed from a plurality of said individual blade segments whereby said individual blade segments comprise an internal passage extending longitudinally from a first end to a second end of each of said blade segments; wherein a plurality of spar members extend longitudinally through said internal passages of each of said blade segments such that said plurality of said spar members are aligned and in communication end-to-end through said internal passages and said plurality of blade segments are aligned and in communication said aligned spar members and define a complete rotor blade from a root that connects to a rotor hub to a blade tip of said rotor blade; and wherein said aligned spar members and blade segments are configured to pivot due to centrifugal forces exerted on said blade segments and aligned spar members, said pivoted spar members and blade segments causing said blade segments to provide a curvature defining a deflection angle relative to the axis of rotation plane of said rotor blade.