System and method for reducing edgewise vibration in a wind turbine rotor bladeand the likelihood of a tower strike in a wind turbine

摘要

The wind turbine comprises a tower, a rotor supported by a tower and including at least one blade 5 which is configured to rotate about a substantially horizontal axis and includes an adjustable stiffening element 21. A sensor is configured to sense a parameter from which deflection of the blade may be determined and a controller acts to adjust the stiffening element in response to signals received from the sensor. The stiffening element preferably comprises a tension element that is anchored to and off-set from a spar extending along the length of the blade and attached to a tensioning device 24 which is preferably located in the hub of the turbine. The blade may include a number of stiffening elements, one or more of which may instead act as compression elements. Also claimed is a wind turbine power plant and a method of operating a wind turbine.