System and method for monitoring blade deflection of wind turbines

Patent metadata

Field	Value
Publication number	US-11639712-B2
Application number	US-202217718545-A
Country	US
Kind code	B2
Filing date	Apr 12, 2022
Priority date	Dec 16, 2016
Publication date	May 2, 2023
Grant date	May 2, 2023

Abstract

Described is a system for monitoring deflection of turbine blades of a wind turbine comprising a tower. The system comprises a position detecting apparatus mounted to the wind turbine, the position detection apparatus comprising position detection components each detecting a presence or absence of a corresponding one of the segments of the turbine blades; and a deflection controller configured to receive the presence or absence detection and to use the presence or absence detection to determine a distance of each of the segments of the turbine blades relative to the tower, whereby the distance of each of the segments of the turbine blades relative to the tower is representative of the deflection of the turbine blades.

First claim

The invention claimed is:

1. A system for monitoring deflection of a turbine blade of a wind turbine comprising a tower having a front, wherein the turbine blade has a tip, the system comprising:
a position detection apparatus configured to be mounted to or about the tower, the position detection apparatus comprising a plurality of position detection components, each one of the plurality of position detection components having a field of detection associated therewith, each one of the position detection components being directed to the front of the tower with the field of view associated therewith crossed by the turbine blade only when the turbine blade undergoes a deflection when passing in front of the tower, with each of the position detection components being configured to detect presence and generate a presence signal when the turbine blade crosses the field of detection associated therewith; and
a deflection controller configured
(i) to receive the presence signal from at least one of the position detection components, and
(ii) to determine a clearance of the tip of the turbine blade relative to the tower when the turbine blade passes in front of the tower based on a) which one of the plurality of position detection components generates the presence signal and b) which one of the plurality of position detection components does not generate the presence signal.

2. The system of claim 1 , wherein the position detection components comprise a pulsed laser source and a sensor.

3. The system of claim 1 , wherein the position detection components are set at distinct angles relative to a horizontal plane.

4. The system of claim 1 , wherein a power ratio of a power associated with a first one of the position detection components over a power associated with a second one of the position detection components is above 5 to 1.

5. The system of claim 1 , wherein a first one of the fields of detection has a first spread angle, a second one of the fields of detection has a second spread angle, and wherein the first spread angle is different from the second spread angle.

6. The system of claim 5 , wherein a spread angle ratio of the first spread angle over the second spread angle is above 2 to 1.

7. The system of claim 1 , wherein the wind turbine further comprises a nacelle and wherein the position detection apparatus is mounted under the nacelle.

8. The system of claim 7 , further comprising at least one of an inclinometer and an accelerometer, wherein at least one of the inclinometer and accelerometer provides data regarding the tower bending or the nacelle undergoing inclination.

9. The system of claim 1 , further comprising a corrective system, wherein the deflection controller triggers actions to be performed by the corrective system upon detection of the clearance being outside an acceptable range.

10. The system of claim 9 , wherein the wind turbine comprise a nacelle mounted to the tower, a hub mounted to the nacelle, with the turbine blade mounted to the hub, wherein the corrective system is adapted to perform at least one of:
altering pitch of at least one of the turbine blade;
modifying blade load by modifying torque demand over the hub;
modifying yawing of the nacelle; and
applying a break on the hub.

11. A wind turbine comprising:
a tower having a front;
a turbine blade having a tip; and
a system for monitoring deflection of the turbine blade comprising:
a position detection apparatus mounted to or about the tower, the position detection apparatus comprising a plurality of position detection components, each one of the plurality of position detection components having a field of detection associated therewith, each one of the position detection components being directed to the front of the tower with the field of view associated therewith crossed by the turbine blade only when the turbine blade undergoes a deflection when passing in front of the tower, with each position detection components being configured to detect presence and generate a presence signal when the turbine blade crosses the field of detection associated therewith; and
a deflection controller configured
(i) to receive the presence signal from at least one of the position detection components, and
(ii) to determine a clearance of the tip of the turbine blade relative to the tower when the turbine blade passes in front of the tower based on a) which one of the plurality of position detection components generates the presence signal and b) which one of the plurality of position detection components does not generate the presence signal.

12. The wind turbine of claim 11 , wherein the position detection components comprise a pulsed laser source and a sensor.

13. The wind turbine of claim 11 , wherein the position detection components are set at distinct angles relative to a horizontal plane.

14. The wind turbine of claim 11 , wherein a first one of the fields of detection has a first spread angle, a second one of the fields of detection has a second spread angle, and wherein the first spread angle is different from the second spread angle.

15. The wind turbine of claim 11 , further comprising a nacelle mounted to the tower, and wherein the position detection apparatus is mounted under the nacelle.

16. A method for monitoring deflection of a turbine blade of a wind turbine comprising a tower and a hub, wherein the turbine blade has a tip and rotate around the hub in rotation cycles, the method comprising the steps of:
having a plurality of position detection components configured to detect and generate a presence signal when the turbine blade crosses a combined field of detection located substantially in front of the tower, each one of the plurality of position detection components having a field of detection associated therewith part of the combined field of detection, the fields of detection not fully overlapping each other, each one of the plurality of position detection components being configured to generate the presence signal when the turbine blade crosses its dedicated field of detection, at least one of the field of detection being crossed by turbine blade only when the turbine blade undergoes deflection; and
determining a clearance of the tip of the turbine blade relative to the tower when the turbine blade passes in front of the tower based on
a) which one of the plurality of the position detection components generates the presence signal when the turbine blade crosses the combined field of detection; and
b) which one of the plurality of position detection components does not generate the presence signal when the turbine blade crosses the combined field of detection during the same rotation cycle.

17. The method of claim 16 , further comprising the steps of: having two neighbor position detection components of the plurality of position detection components having their dedicated fields of detections side-by-side, each of the two neighbor position detection components generating a signal when detecting that the turbine blade crosses their dedicated field of detection; and determining that the turbine blade crosses the combined field of detection based on at least one of the neighbor position detection components generating the presence signal.

18. The method of claim 16 , comprising the steps of: detecting a distance between a first one of the plurality of position detection components and the turbine blade when crossing the combined field of detection, and establishing the presence signal when the detected distance is under a threshold.

19. The metho

Assignees

• Innergex Inc
• Institut Nat Doptique

Inventors

• David Vincent
• Cantin Daniel
• Guillemette Robert
• Cloutier Jonathan

Classifications

• F03D7/0236

  by changing the active surface of the wind engaging parts, e.g. reefing or furling · CPC title

• F05B2270/804

  Optical devices · CPC title

• F05B2270/17

  to avoid excessive deflection of the blades · CPC title

• F03D17/00 Primary

  Monitoring or testing of wind motors, e.g. diagnostics (testing during commissioning of wind motors F03D13/30) · CPC title

• F05B2270/33

  Proximity of blade to tower · CPC title