| 摘要 |
The invention relates to a method and arrangement to measure the deflection of a blade of a wind-turbine. The blade comprises a cavity inside the blade. A reflector, which is located inside the cavity of the blade, is coupled by a wire-less signal with a distance-measurement-device. The distance--measurement-device uses the wireless signal to measure the distance between the distance-measurement-device and the reflector. A line of sight is established and maintained between the distance-measurement-device and the reflector even when the blade is deflected. The reflector is inclined relative to the line of sight in a way, that a lateral movement of the reflector relative to the line of sight results in a change of the distance between the distance-measurement--device and the reflector, while the lateral movement is caused by an deflection of the blade. The distance--measurement-device is designed to measure the change of the distance, which is used to determine the deflection of the blade. |
