System and Method of In Situ Wind Turbine Blade Monitoring
Systems and methods are disclosed for monitoring parameters such as the material properties or structural integrity of a wind turbine blade on a wind turbine. An example method comprises detecting light reflected from a wind turbine blade, generating a value based on the detecting, comparing the value to a threshold value and determining a parameter of the wind turbine blade based on the comparing. A further embodiment comprises determining a wind velocity by detecting reflected light from a target area in front of the wind turbine blade. An example system comprises a detector configured to detect light reflecting from a turbine blade and to produce a value representative of the detected light. The system also comprises a comparator configured to compare the value to a threshold value and to determine a parameter of the turbine blade.
1 . A method comprising:
detecting light reflected from a wind turbine blade;
generating a value based on the detecting;
comparing the value to a threshold value; and
determining a parameter of the wind turbine blade based on the comparing.
2 . The method of claim 1 , wherein the detecting is performed during operation of the wind turbine blade.
3 . The method of claim 1 , wherein the detecting is performed from a nacelle of a wind turbine coupled to the wind turbine blade.
4 . The method of claim 1 , wherein the detecting is performed using a laser Doppler velocimeter.
5 . The method of claim 1 , further comprising:
determining a wind velocity by detecting the reflected light from a target area in front of the wind turbine blade, and
determining the parameter of the wind turbine blade by detecting the reflected light from the wind turbine blade.
6 . The method of claim 1 , wherein the threshold value is based on higher-order harmonic frequencies derived from light pulse signatures based on similar wind turbine blades.
7 . The method of claim 6 , wherein the comparing further comprises comparing the value to a higher-order harmonic frequency.
8 . The method of claim 1 , further comprising comparing the parameter to a range of parameters representing a lifetime of the wind turbine blade.
9 . The method of claim 1 , further comprising generating an output signal indicating a remaining lifetime of the wind turbine blade.
10 . A system, comprising:
a detector configured to detect light reflecting from a turbine blade and to produce a value representative of the detected light; and
a comparator configured to compare the value to a threshold value and to determine a parameter of the turbine blade.
11 . The system of claim 10 , wherein the detector detects the reflected light during operation of the turbine blade.
12 . The system of claim 10 , wherein the detector is mounted on a nacelle of a wind turbine the includes the turbine blade.
13 . The system of claim 10 , wherein the detector is a laser Doppler velocimeter.
14 . The system of claim 10 , wherein the detector is configure to:
determine a wind velocity by detecting the reflected light from a target area in front of the turbine blade; and
determine the parameter by detecting the reflected light from the turbine blade.
15 . The system of claim 10 , wherein the comparator is further configured to compare the value to a threshold that is based on higher-order harmonic frequencies derived from light pulse signatures based on similar wind turbine blades.
16 . The system of claim 15 , wherein the comparator is further configured to compare the value to a higher-order harmonic frequency.
17 . The system of claim 10 , wherein the comparator is further configured to compare the parameter to a range of parameters representing a lifetime of the wind turbine blade.
18 . The system of claim 10 , further comprising an output signal generator configured to generate an output signal indicating a remaining lifetime of the wind turbine blade.