Methods and systems for controlling a wind turbine

Patent metadata

Field	Value
Publication number	US-10280897-B2
Application number	US-201514964622-A
Country	US
Kind code	B2
Filing date	Dec 10, 2015
Priority date	Dec 10, 2015
Publication date	May 7, 2019
Grant date	May 7, 2019

Abstract

A method for controlling a wind turbine includes receiving signals representative of oncoming wind speeds approaching at least a portion of a wind turbine, receiving background noise and signals representative of signal-to-noise ratios corresponding to the signals representative of the oncoming wind speeds, determining an availability-and-atmospheric noise in the signals based on one or more of the signal-to-noise ratios, blade positions of blades of the wind turbine, and the yaw position of a nacelle of the wind turbine, determining a wind incoherence noise in the signals due to a change in the oncoming wind speeds while approaching at least the portion of the wind turbine, determining a net measurement noise in the signals based on the background noise, the availability-and-atmospheric noise, and the wind incoherence noise, and controlling the wind turbine based at least on the signals representative of the oncoming wind speeds and the net measurement noise.

First claim

The invention claimed is:

1. A method for controlling a wind turbine, comprising:
receiving signals representative of oncoming wind speeds approaching at least a portion of a wind turbine;
receiving background noise and signals representative of signal-to-noise ratios corresponding to the signals representative of the oncoming wind speeds;
determining an availability-and-atmospheric noise in the signals representative of the oncoming wind speeds based on one or more of the signal-to-noise ratios, blade positions of blades of the wind turbine, and a yaw position of a nacelle of the wind turbine;
determining a wind incoherence noise in the signals representative of the oncoming wind speeds due to a change in the oncoming wind speeds while approaching at least the portion of the wind turbine, wherein determining the wind incoherence noise comprises:
determining a plurality of cross-correlation coefficients corresponding to a plurality of distances between a plurality of range locations;
determining a plurality of regression coefficients based on the plurality of cross-correlation coefficients and the plurality of distances between the plurality of range locations;
determining coherence loss based on the plurality of regression coefficients and the plurality of distances between the plurality of range locations;
determining the wind incoherence noise based on the coherence loss;

determining a net measurement noise in the signals representative of the oncoming wind speeds based on the background noise, the availability-and-atmospheric noise, and the wind incoherence noise; and
controlling the wind turbine based at least on the signals representative of the oncoming wind speeds and the net measurement noise.

2. The method of claim 1 , wherein determining the net measurement noise comprises determining a square root of a sum of squares of the background noise, the availability-and-atmospheric noise, and the wind incoherence noise.

3. The method of claim 1 , further comprising:
measuring atmospheric data for a determined time period at a potential location of installation of the wind turbine; and
determining an atmospheric constant based on the atmospheric data.

4. The method of claim 3 , wherein determining the atmospheric constant comprises fitting a curve to the atmospheric data.

5. The method of claim 4 , wherein determining the availability-and-atmospheric noise in the oncoming wind speeds comprises:
determining an availability-and-atmospheric noise constant based on one or more of a number of laser pulses used for measuring the signals representative of the oncoming wind speeds, the atmospheric constant, and a wavelength of a laser used for measuring the signals representative of the oncoming wind speeds; and
determining the availability-and-atmospheric noise based on the signal-to-noise ratios and the availability-and-atmospheric noise constant.

6. The method of claim 1 , wherein determining the availability-and-atmospheric noise comprises determining an exponential function of the signal-to-noise ratios.

7. The method of claim 1 , wherein receiving the signals representative of the oncoming wind speeds comprises receiving signals representative of range wind speeds at the plurality of range locations, and wherein the range wind speeds comprise at least a first range wind speed and a second range wind speed.

8. The method of claim 1 , wherein determining the plurality of regression coefficients comprises applying a regression analysis technique to the plurality of cross-correlation coefficients and the plurality of distances between the plurality of range locations.

9. The method of claim 7 , wherein determining the plurality of cross-correlation coefficients comprises:
determining the first range wind speed at a first range location in the plurality of range locations;
determining the second range wind speed at a second range location in the plurality of range locations; and
applying a cross-correlationship function to the first range wind speed and the second range wind speed to determine the plurality of cross-correlation coefficients.

10. The method of claim 1 , wherein controlling the wind turbine comprises changing pitch angles of a plurality of blades of the wind turbine.

11. A wind turbine system, comprising:
a wind turbine comprising a rotor and a plurality of blades mounted on the rotor;
a LIDAR based sensing device disposed on the wind turbine and configured to measure signals representative of oncoming wind speeds approaching at least a portion of the wind turbine and signal-to-noise ratios corresponding to the signals representative of the oncoming wind speeds;
a processing subsystem operatively coupled to the LIDAR based sensing device and the wind turbine and comprising:
a first noise-determination unit configured to determine an availability-and-atmospheric noise in the signals representative of the oncoming wind speeds based on one or more of the signal-to-noise ratios, blade positions of the plurality of blades, and a yaw position of a nacelle of the wind turbine;
a second noise-determination unit configured to determine a wind incoherence noise in the signals representative of the oncoming wind speeds due to a change in the oncoming wind speeds while approaching at least the portion of the wind turbine wherein to determine the wind incoherence noise in the signals representative of the oncoming wind speeds, the second noise-determination unit is configured to:
determine a plurality of cross-correlation coefficients corresponding to a plurality of distances between a plurality of range locations;
determine a plurality of regression coefficients based on the plurality of cross-correlation coefficients and the plurality of distances between the plurality of range locations;
determine coherence loss based on the plurality of regression coefficients and the plurality of distances between the plurality of range locations;
determine the wind incoherence noise based on the coherence loss;

a third noise-determination unit configured to determine a net measurement noise in the signals representative of the oncoming wind speeds based on background noise, the availability-and-atmospheric noise, and the wind incoherence noise; and
a control unit configured to control the wind turbine based on the signals representative of the oncoming wind speeds and the net measurement noise.

12. The wind turbine system of claim 11 , wherein the LIDAR based sensing device comprises a pulsed LIDAR, a continuous LIDAR, or a Doppler pulsed LIDAR.

13. The wind turbine system of claim 11 , wherein the LIDAR based sensing device is disposed on or inside one or more of a nacelle of the wind turbine, a hub of the wind turbine, and a spinner of the rotor, at the bottom of the tower, or combinations thereof.

14. The wind turbine system of claim 11 , wherein the third noise-determination unit is further configured to determine the net measurement noise by determining a square root of a sum of squares of the background noise, the availability-and-atmospheric noise, and the wind incoherence noise.

15. The wind turbine system of claim 11 , wherein the first noise-determination unit is configured to:
determine an availability-and-atmospheric noise constant based on one or more of a number of laser pulses used for measuring the signals representative of the oncoming wind speeds, an atmospheric constant, and a wavelength of a laser used for measuring the signals representative of the oncoming wind speeds; and
determine the availability-and-atmospheric noise based on the signal-to-noise ratios and the availabi

Assignees

• Gen Electric

Inventors

• Markham Thomas Stephen
• Davoust Samuel

Classifications

• F05B2270/1033

  Power (if explicitly mentioned) · CPC title

• F03D7/0204

  for orientation in relation to wind direction · CPC title

• F05B2270/1011

  to prevent overspeed · CPC title

• Y02E10/723

  Cross-Sectional Technologies · mapped topic

• F05B2270/8042

  Lidar systems · CPC title