Apparatus to detect aerodynamic conditions of blades of wind turbines
View Patent ↗Apparatus for detecting aerodynamic conditions of a rotor blade ( 22 ) of a wind turbine ( 10 ). An acoustic sensor ( 24 ) may be remotely located from the rotor blade. The sensor may be focused to monitor a portion of a blade path swept by the rotor blade to detect an aerodynamic condition such as flow separation, and may provide input to a controller ( 27 ) for control of a pitch of the blade effective to prevent the flow separation from developing into a full stall condition. One sensor may be focused to monitor blades of more than one wind turbine. A plurality of such sensors in a wind park may be connected to a supervisory controller ( 120 ) to predict the propagation of wind conditions progressing through the park.
1. Apparatus comprising:
a wind turbine having at least one rotor blade; and
at least one acoustic sensor remotely located from the at least one rotor blade, said at least one acoustic sensor focused to monitor a portion of a blade path comprising a circumferential sector on a radially outer portion of the blade path swept by said at least one rotor blade to detect an aerodynamic condition affecting the blade in the portion of the blade path being monitored, wherein said at least one acoustic sensor has a listening-field configured to listen to sounds emanating from the circumferential sector over the radially outer portion of the blade path being monitored, while attenuating sounds emanating outside the circumferential sector on the radially outer portion of the blade path being monitored.
2. The apparatus of claim 1 , wherein said at least one acoustic sensor comprises a unidirectional acoustic sensor.
3. The apparatus of claim 1 , further comprising an acoustic condenser coupled to said at least one acoustic sensor.
4. The apparatus of claim 1 , wherein said at least one acoustic sensor comprises a further acoustic sensor focused to monitor a different portion of the blade path swept by said at least one rotor blade to detect an aerodynamic condition affecting the blade in at least the different portion of the blade path.
5. The apparatus of claim 1 , wherein said at least one acoustic sensor comprises an array of acoustic sensors.
6. The apparatus of claim 5 , wherein the array of acoustic sensors is disposed about a perimeter of a nacelle of the wind turbine to detect an aerodynamic condition affecting the blade in at least one of a plurality of circumferential sectors of the blade path swept by the at least one rotor blade.
7. The apparatus of claim 6 , wherein each of the acoustic sensors in the array is respectively focused towards at least one of the plurality of circumferential sectors of the blade path swept by said at least one rotor blade.
8. The apparatus of claim 1 , wherein said at least one acoustic sensor comprises an array of electronically-steerable acoustic sensors.
9. The apparatus of claim 8 , wherein the array of electronically-steerable acoustic sensors is dynamically focused to the portion of the blade path to detect the aerodynamic condition.
10. A wind park comprising a plurality of wind turbines as recited in claim 1 , and further comprising a supervisory controller responsive to detected aerodynamic conditions affecting respective rotor blades of at least some of the plurality of wind turbines, the supervisory controller configured to estimate atmospheric conditions likely to propagate through the park, and to predict aerodynamic conditions likely to affect respective rotor blades of at least some other ones of the plurality of wind turbines.
11. The apparatus of claim 1 , wherein said at least one acoustic sensor is focused to monitor a radially outer portion of the blade path effective to detect a flow separation condition.
12. The apparatus of claim 11 , further comprising a controller responsive to said at least one acoustic sensor to adjust a pitch angle of said at least one rotor blade to prevent the flow separation condition from progressing to a stall condition.
13. Apparatus comprising:
at least two wind turbines each having at least one respective rotor blade; and
at least one acoustic sensor array remotely located from the respective rotor blades of said at least two wind turbines, said at least one acoustic sensor array focused to monitor respective portions comprising respective circumferential sectors on radially outer portions of the blade paths swept by the respective rotor blades of the at least two wind turbines, the monitored portions of the respective blade paths effective to detect an aerodynamic condition affecting at least one blade in at least one of the respective portions of the blade paths swept by the respective rotor blades of said at least two wind turbines, wherein said at least one acoustic sensor array has a listening-field configured to listen to sounds emanating from the respective circumferential sectors on the radially outer portions of the blade paths being monitored, while attenuating sounds outside the respective circumferential sectors on the radially outer portions of the blade paths being monitored.
14. The apparatus of claim 13 , wherein said at least one acoustic sensor comprises an array of electronically-steerable acoustic sensors.
15. Apparatus for a wind turbine having at least one rotor blade comprising:
at least one acoustic sensor remotely located from the at least one rotor blade, said at least one acoustic sensor focused to monitor a portion comprising a circumferential sector on a radially outer portion of a blade path swept by said at least one rotor blade to detect an aerodynamic condition affecting the blade in the portion of the blade path being monitored, wherein said at least one acoustic sensor has a listening configured to listen to sounds emanating from the circumferential sector on the radially outer portion of the blade path being monitored, while attenuating sounds emanating outside the circumferential sector on the radially outer portion of the blade path being monitored.
16. The apparatus of claim 15 , wherein said at least one acoustic sensor is focused to monitor a radially outer portion of the blade path effective to detect an incipient stall condition.
17. The apparatus of claim 15 , wherein said at least one acoustic sensor comprises an array of acoustic sensors.
18. The apparatus of claim 17 , wherein the array of acoustic sensors is disposed about a perimeter of a nacelle of the wind turbine to detect an aerodynamic condition affecting the blade in at least one of a plurality of circumferential sectors of the blade path swept by the at least one rotor blade.
19. The apparatus of claim 15 , wherein said at least one acoustic sensor comprises an array of electronically-steerable acoustic sensors which is dynamically focused to the portion of the blade path to detect the aerodynamic condition.
20. The apparatus of claim 15 , further comprising a supervisory controller in a wind park responsive to detected aerodynamic conditions affecting respective rotor blades of at least some of a plurality of wind turbines in the wind park, the supervisory controller configured to estimate atmospheric conditions likely to propagate through the park over a time horizon, and to predict aerodynamic conditions likely to affect over the time horizon respective rotor blades of at least some other ones of the plurality of wind turbines.