Wind turbine and vibration damping method thereof

Abstract

There are provided a TMD adjusted to damp vibration in a natural frequency of a wind turbine, an AVC adjusted to damp vibration in a variable frequency of turbulent wind flowing into the wind turbine and/or a frequency of a rotation speed of a wind-turbine blade, and a pitch-angle control portion provided with a correction portion which adjusts a damping frequency of the AVC. The AVC is configured to obtain the damping force by changing the pitch angle of the wind-turbine blade.

What is claimed is: 
     
         1 . A wind turbine comprising:
 a passive damper adjusted to damp vibration in a natural vibration frequency of the wind turbine;   an active damper adjusted to damp variation in a variable frequency of turbulent wind flowing into the wind turbine and/or variation in a n-th (n is a natural number) frequency of a rotation speed of a wind-turbine blade; and   an active-damper control portion which adjusts a damping frequency of the active damper.   
     
     
         2 . The wind turbine according to  claim 1 , wherein
 the active damper obtains the damping force by changing a pitch angle of the wind-turbine blade.   
     
     
         3 . The wind turbine according to  claim 1 , further comprising:
 an anemometer which detects a flow speed of wind flowing into the wind turbine, wherein   the active-damper control portion controls the active damper on the basis of the wind speed detected by the anemometer.   
     
     
         4 . The wind turbine according to  claim 2 , further comprising:
 an anemometer which detects a flow speed of wind flowing into the wind turbine, wherein   the active-damper control portion controls the active damper on the basis of the wind speed detected by the anemometer.   
     
     
         5 . The wind turbine according to  claim 1 , wherein
 the passive damper is a tuned mass damper; and   the tuned mass damper uses a wind-turbine constituent element made relatively movable with respect to a wind-turbine main body as an added mass.   
     
     
         6 . The wind turbine according to  claim 2 , wherein
 the passive damper is a tuned mass damper; and   the tuned mass damper uses a wind-turbine constituent element made relatively movable with respect to a wind-turbine main body as an added mass.   
     
     
         7 . The wind turbine according to  claim 3 , wherein
 the passive damper is a tuned mass damper; and   the tuned mass damper uses a wind-turbine constituent element made relatively movable with respect to a wind-turbine main body as an added mass.   
     
     
         8 . The wind turbine according to  claim 4 , wherein
 the passive damper is a tuned mass damper; and   the tuned mass damper uses a wind-turbine constituent element made relatively movable with respect to a wind-turbine main body as an added mass.   
     
     
         9 . The wind turbine according to  claim 1 , wherein
 the passive damper is a tuned liquid damper; and   the tuned liquid damper uses operating oil or lubricant oil stored in the wind-turbine main body as an added mass.   
     
     
         10 . The wind turbine according to  claim 2 , wherein
 the passive damper is a tuned liquid damper; and   the tuned liquid damper uses operating oil or lubricant oil stored in the wind-turbine main body as an added mass.   
     
     
         11 . The wind turbine according to  claim 3 , wherein
 the passive damper is a tuned liquid damper; and   the tuned liquid damper uses operating oil or lubricant oil stored in the wind-turbine main body as an added mass.   
     
     
         12 . The wind turbine according to  claim 4 , wherein
 the passive damper is a tuned liquid damper; and   the tuned liquid damper uses operating oil or lubricant oil stored in the wind-turbine main body as an added mass.   
     
     
         13 . A vibration damping method of a wind turbine provided with a passive damper adjusted to damp vibration in a natural frequency of the wind turbine and an active damper, comprising
 controlling a damping frequency of the active damper so as to damp vibration in a variable frequency of turbulent wind flowing into the wind turbine and/or variation in a n-th (n is a natural number) frequency of a rotation speed of a wind-turbine blade.