Wind turbine with a broad-band damping device in each blade

Abstract

Wind turbine comprising one or more blades, incorporating in each blade a damping device comprising a first damping element tuned at the main resonance frequency of the blade Ω o and K additional damping elements tuned at frequencies Ω 1, Ω 2 , . . . Ω k so that in the event of blade vibrations its amplitude A is reduced in a percentage Y of the amplitude Ao at the main resonance frequency of the blade Ω o in a band extended above and below the main resonance frequency of the blade Ω o in a percentage X of Ω o, said frequencies Ω 1, Ω 2 , . . . Ω k being comprised within said band.

1 . Wind turbine comprising one or more blades, characterized in that each blade incorporates a damping device comprising a first damping element tuned at the main resonance frequency of the blade Ω o  and K additional damping elements tuned at frequencies Ω 1 , Ω 2 , . . . Ω k , so that in the event of blade vibrations its amplitude A is reduced in a percentage Y of the amplitude A o  at the main resonance frequency of the blade Ω o  in a band extended above and below the main resonance frequency of the blade Ω o  in a percentage X of Ω o , said frequencies Ω 1 , Ω 2 , . . . Ω k  being comprised within said band. 
     
     
         2 . Wind turbine according to  claim 1 , wherein said damping device is placed in a blade section where the twist is 0° in order to attenuate edgewise vibrations. 
     
     
         3 . Wind turbine according to  claim 1 , wherein said damping device is placed in a blade section with a predefined twist in order to attenuate both edgewise and flapwise vibrations. 
     
     
         4 . Wind turbine according to  claim 1 , wherein said damping device is placed in a blade section on the location of the second edgewise vibration modal shape to avoid excitation of hybrid vibration modes. 
     
     
         5 . Wind turbine according to any of claims  claim 1 , wherein the number of said additional damping elements is two. 
     
     
         6 . Wind turbine according to  claim 5 , wherein said percentage Xis lesser than 15%. 
     
     
         7 . Wind turbine according to  claim 6 , wherein said percentage Xis lesser than 11%. 
     
     
         8 . Wind turbine according to any of claims  claim 5 , wherein said percentage Y is lesser than 40%. 
     
     
         9 . Wind turbine according to  claim 8 , wherein said percentage Y is lesser than 25%. 
     
     
         10 . Wind turbine according  claim 1 , wherein its regulation system is a stall regulation system. 
     
     
         11 . Wind turbine according to  claim 1 , wherein its regulation system is a pitch regulation system.