Method and system for improving wind farm power production efficiency

Patent metadata

Field	Value
Publication number	US-9512820-B2
Application number	US-201313770125-A
Country	US
Kind code	B2
Filing date	Feb 19, 2013
Priority date	Feb 19, 2013
Publication date	Dec 6, 2016
Grant date	Dec 6, 2016

Abstract

A method and system for improving power production efficiency on a wind farm having of a plurality of spatially distributed wind turbines is provided. The method includes receiving a wind measurement that includes a wind direction impinging on a turbine ( 20 ), determining a misalignment of the wind turbine with respect to the wind direction, and activating a wake steering control for the wind turbine ( 20 ) to implement the misalignment of the wind turbine ( 20 ) with the wind direction such that the misalignment is adapted to steer a wake of the wind turbine away from a neighboring wind turbine ( 30 ). A wind turbine arrangement including a nacelle, a yaw controller, and a yaw drive is also provided.

First claim

The invention claimed is:

1. A method implemented on a wind farm having a plurality of spatially distributed wind turbines for improving power production efficiency, comprising:
storing data indicative of a layout of the wind farm, the layout comprising spatial relationships of the plurality of spatially distributed wind turbines of the wind farm including a first wind turbine of the wind farm and a neighboring wind turbine of the wind farm;
receiving a wind measurement comprising a wind direction impinging on the first wind turbine of the wind farm;
determining by a processor a misalignment of the first wind turbine with respect to the wind direction, wherein the misalignment is adapted to steer a wake of the first wind turbine away from the neighboring wind turbine of the wind farm, wherein the determining by the processor of the misalignment of the first wind turbine with respect to the wind direction is configured to provide a variable degree of avoidance by the neighboring wind turbine of the wake of the first wind turbine based on the stored spatial relationships of the first wind turbine relative to the neighboring wind turbine, wherein the processor determines a deflection angle of the wake based on φ=0.6αθ, where “a” is the axial induction factor and θis a degree of the misalignment of the first wind turbine relative to the wind direction impinging on the first wind turbine; and
activating a wake steering control for the first wind turbine by producing a control signal adapted to implement the misalignment of the first wind turbine with the wind direction,
wherein the wake steering control is adapted to produce a control signal that directs the first wind turbine to yaw in a positive direction when the wind direction is impinging at a negative angle, and to yaw in a negative direction when the wind direction is impinging at a positive angle,
wherein the yaw angle in the positive direction comprises an angle of approximately +70° when the neighboring wind turbine is located at a distance of approximately 4D downstream from the first turbine and the wind direction is impinging on the first wind turbine an angle of approximately 0°, where D represent units of diameter, wherein when the yaw angle in the positive direction is approximately +70°, the wake of the first wind turbine fully avoids the neighboring wind turbine,
wherein the yaw angle in the negative direction comprises an angle of approximately −70° when the neighboring wind turbine is located at the distance of approximately 4D downstream from the first turbine and the wind direction is impinging on the first wind turbine at a an angle of approximately 0°, wherein when the yaw angle in the negative direction is approximately −70°, the wake of the first wind turbine fully avoids the neighboring wind turbine.

2. The method of claim 1 wherein determining the misalignment of the first wind turbine comprises determining based on the wind direction whether the wake of the first wind turbine impinges on the neighboring wind turbine.

3. The method of claim 1 wherein determining the misalignment of the first wind turbine comprises determining based on the wind direction an amount of the wake of the first wind turbine that impinges on the neighboring wind turbine.

4. The method of claim 1 wherein an amount of the misalignment of the first wind turbine with respect to the wind direction is dependent on an angle and a distance between the first wind turbine and the neighboring wind turbine.

5. The method of claim 1 wherein an amount of the misalignment of the first wind turbine with respect to the wind direction determined is inversely proportional to a proximal distance between the first wind turbine and the neighboring wind turbine.

6. The method of claim 1 further comprising realigning the first wind turbine with respect to the wind direction when the wind direction is outside a predetermined range of angles for the wind direction impinging on the first wind turbine.

7. The method of claim 1 further comprising implementing the misalignment by rotating a nacelle of the first wind turbine leading to the misalignment of the first wind turbine with the wind direction, thereby narrowing an influence of the wake on the neighboring wind turbine geometrically.

8. The method of claim 1 , further comprising the processor monitoring a combined power production of the first wind turbine and the neighboring wind turbine, executing a control function that determines the misalignment that maximizes the combined power production, and executing a learning algorithm that optimizes the control function to further increase the combined power production over time.

9. The method of claim 8 , wherein the control function provides a first yaw adjustment curve for a range of negative incoming wind directions relative to a line between the first wind turbine and the neighboring wind turbine, a second yaw adjustment curve for a range of positive incoming wind directions relative to said line, and the first and second yaw adjustment curves are discontinuous with each other only for an incoming wind direction aligned with said line.

10. The method of claim 1 , further comprising the processor determining the misalignment by executing a control function selected from an array of control functions based on a distance between the first wind turbine and the neighboring wind turbine, and the processor monitors a combined power production of the first wind turbine and the neighboring wind turbine and executes a learning algorithm that adjusts the control functions in the array based on the combined power resulting therefrom to further increase the combined power production over time.

11. The method of claim 1 , wherein the processor determines the misalignment to produce a maximum combined power production of the first wind turbine and the neighboring wind turbine based on a distance there between, the wind direction relative to a line there between, and at least one of: a) a horizontal narrowing of the wake resulting from the misalignment, and b) the deflection angle of the wake resulting from the misalignment.

12. A system for improving power production efficiency on a wind farm having a plurality of spatially distributed wind turbines, comprising:
a data storage device for storing data indicative of a layout of the wind farm, the layout comprising spatial relationships of the plurality of spatially distributed wind turbines of the wind farm including a first wind turbine of the wind farm and a neighboring wind turbine of the wind farm;
a data processing device for receiving a wind measurement comprising a wind direction impinging on a first wind turbine of the wind farm; determining a misalignment of the first wind turbine with respect to the wind direction, wherein the misalignment is adapted to steer a wake of the first wind turbine away from a neighboring wind turbine of the wind farm, wherein the determining by the data processing device of the misalignment of the first wind turbine with respect to the wind direction is configured to provide a variable degree of avoidance by the neighboring wind turbine of the wake of the first wind turbine based on the stored spatial relationships of the first wind turbine relative to the neighboring wind turbine, wherein the data processing device further determines a deflection angle of the wake resulting from the misalignment, wherein the processor determines the deflection angle of the wake based on an axial induction factor of the first wind turbine and an amount of the misalignment; and
activating a wake steering control for the first wind turbine by producing a control signal adapted to implement the misalignment

Assignees

• Obrecht John M
• Siemens Ag

Inventors

• Obrecht John M

Classifications

• F05B2270/329

  Azimuth or yaw angle · CPC title

• F05B2270/20

  to optimise the performance of a machine · CPC title

• F03D7/048

  controlling wind farms · CPC title

• F03D7/0204 Primary

  for orientation in relation to wind direction · CPC title

• F05B2270/321

  Wind directions · CPC title