SENSOR DEVICE FOR MEASURING AERODYNAMIC LOADS OF A ROTOR BLADE OF A WIND TURBINE

• US 20140003942A1
• Filed: 02/22/2012
• Published: 01/02/2014
• Est. Priority Date: 03/19/2011
• Status: Active Grant

• Current Assignee: Nidec SSB Wind Systems GmbH (Emerson Electric Company)
• Original Assignee: SSB Wind Systems GmbH & Co., KG
• Inventors: Bertolotti, Fabio, Ktting, Norbert
• Granted Patent: US 9,657,720 B2
• Time in Patent Office: Days
• US Class Current: 416/61
• CPC Class Codes: F03D 17/00 Monitoring or testing of wind motors, e.g. diagnostics testing during commissioning of wind motors F03D13/30
• CPC Class Codes: F03D 80/55 Cleaning F03D80/40 takes precedence
• CPC Class Codes: F05B 2270/804 Optical devices
• CPC Class Codes: F05B 2270/821 Displacement measuring means, e.g. inductive
• CPC Class Codes: G01B 11/16 for measuring the deformation in a solid, e.g. optical strain gauge
• CPC Class Codes: G01M 5/0016 of aircraft wings or blades
• CPC Class Codes: G01M 5/0041 by determining deflection or stress
• CPC Class Codes: G01M 5/0091 by using electromagnetic excitation or detection
• CPC Class Codes: G02B 27/0006 with means to keep optical surfaces clean, e.g. by preventing or removing dirt, stains, contamination, condensation G02B1/18 takes precedence; cleaning in general B08B
• CPC Class Codes: Y02E 10/72 Wind turbines with rotation axis in wind direction

Abstract

A sensor device for measuring aerodynamic loads of a rotor blade for a wind power installation . The sensor device includes a reflector arranged in a cavity of the rotor blade which signals a signal evaluation device arranged at a distance from the reflector. The signal evaluation device detects and quantifies physical changes of the rotor blade from the reflected signal. A cleaning device for the reflector is arranged on the reflector for activation by a centrifugal force generated during the rotation of the rotor to clean the reflector.

Claims

1-18. -18. (canceled)

19. A sensor device for measuring aerodynamic loads of a wind turbine rotor blade comprising:

a reflector arranged in a cavity of a rotor blade extending from a rotor hub;

a signal evaluation device arranged at a distance from the reflector and operable to receive a signal from the reflector, the signal evaluation device detecting and quantifying a physical change of the rotor blade from the reflector signal; and

a cleaning device associated with the reflector for cleaning the reflector, the cleaning device being activated by a centrifugal force generated during rotation of the rotor.

20. The sensor device of claim 19 wherein the cleaning device is activated in response to an increase in hydraulic or pneumatic pressure with increasing centrifugal force.

21. The sensor device of claim 19 wherein the cleaning device comprises a sprayer having a storage tank adapted to be filled with a cleaning agent, an activation unit that responds to the centrifugal force, and a line in fluid communication between the storage tank and a discharge nozzle arranged on the sensor.

22. The sensor device of claim 19 wherein the reflector has a reflector surface arranged substantially transverse to the signal path and which is cleaned by the cleaning device.

23. The sensor device of claim 19 wherein the reflector in the direction of the signal evaluation device comprises a protective shield arranged in front of the reflector surface and which does not interfere with the signal, a surface of the protective shield points in the direction of the signal evaluation device and is cleaned by the cleaning device.

24. The sensor device of claim 23 wherein the protective shield, together with the reflector surface forms a solid bond that is impenetrable to air.

25. The sensor device of claim 23 wherein the reflector and the protective shield are arranged in a housing.

26. The sensor device of claim 25 wherein the protective shield forms a cover for the housing arranged in the direction of the evaluation device and the cleaning device is arranged on the surface of the protective shield pointing in the direction of the evaluation device.

27. The device of claim 23 wherein the protective shield is arranged in relation to the reflector surface in a plane that is angled and opens out in the direction of a signal path.

28. The sensor device of claim 19, wherein the cleaning device is operable for activation when the rotor hub is rotating slowly and deactivation when the hub is rotating quickly.

29. The sensor device of claim 19, wherein the cleaning device comprises a wiper device with a wiper arm operable to swivel across a reflector surface.

30. The sensor device of claim 29, wherein the wiper arm further comprises a sealing lip pointing in the direction of the reflector surface, wherein the wiper arm is rotatable from a starting position into a wiping position over the reflector surface, and in the starting position is arranged at a side edge of the reflector surface.

31. The sensor device of claim 29, wherein the wiper arm is activated as a function of rotor hub rotation.

32. The sensor device of claim 31, wherein the wiper arm only wipes across the reflector surface when the hub is rotating at low speeds and remains in the starting position when the hub is rotating at high speeds.

33. The sensor device of claim 31, wherein the wiper arm remains in the starting position when the centrifugal force acting on the reflector is high.

34. The sensor device of claim 32, wherein at low rotor speed the wiping operation takes place by means of the force of gravity (g) acting on the reflector as a result of rotation of the rotor blade.

35. The sensor device of claim 29, wherein the wiper arm in its starting position is supported adjacent a side edge of the protective shield surface and in the wiping position rotates over the protective shield surface.

36. The sensor device of claim 19 in combination with wind turbine comprising:

a rotor that can rotate about a rotor axis by wind power, the rotor having a rotor hub and at least one rotor blade secured to the rotor hub and extending therefrom in a direction substantially transversal to the rotor axis;

at least one electrical generator, which is mechanically coupled to the rotor and driven thereby.