Wind turbine power generation facility and method of operating the same

1. A wind turbine power generation facility, comprising:

at least one wind turbine power generating apparatus including a blade;

a lightning sensor for detecting or predicting occurrence of lightning in an installation area of the at least one wind turbine power generating apparatus, prior to lightning strike to the blade; and

a controller for switching an operation mode of the at least one wind turbine power generating apparatus to a lightning-protection mode in which a rotor rotation speed is lower than a rated rotation speed so as to prevent the lightning strike on an unexpected portion on the blade of the at least one wind turbine power generating apparatus, on a basis of an output signal of the lightning sensor,

wherein the controller is configured to shift a state of the at least one wind turbine power generating apparatus to a standby state as the lightning-protection mode in which power generation is stopped without fixing a rotor, upon switching to the lightning-protection mode, and

wherein the lightning-protection mode satisfies at least one of a first condition that the rotor rotation speed of the at least one wind turbine power generating apparatus is 2 rpm or less, or a second condition that a blade tip speed of the at least one wind turbine power generating apparatus is 15 m/s or less.

2. The wind turbine power generation facility according to claim 1 ,

wherein the at least one wind turbine power generating apparatus has a rotor diameter of 70 m or more.

3. The wind turbine power generation facility according to claim 1 ,

wherein the lightning sensor includes at least one of an optical sensor for detecting light which occurs accompanying the lightning, or a sonic sensor for detecting sound which occurs accompanying the lightning.

4. The wind turbine power generation facility according to claim 1 ,

wherein the lightning sensor includes an electromagnetic-wave sensor for detecting electromagnetic waves which occur accompanying the lightning.

5. The wind turbine power generation facility according to claim 1 ,

wherein the lightning sensor includes an electric-charge sensor configured to detect electric charge accumulated in cloud or on ground.

6. The wind turbine power generation facility according to claim 1 ,

wherein the lightning sensor includes a coherer.

7. The wind turbine power generation facility according to claim 1 ,

wherein the controller includes a processor configured to receive the output signal of the lightning sensor and to determine whether to switch the operation mode to the lightning-protection mode in accordance with operation-mode switching logics.

8. The wind turbine power generation facility according to claim 1 ,

wherein the lightning sensor is configured to detect light or sound of the lightning, and

the controller is configured to switch the operation mode of the at least one wind turbine power generating apparatus to the lightning-protection mode in response to the lightning sensor detecting the light or sound of the lightning.

9. A method of operating a wind turbine power generation facility including at least one wind turbine power generating apparatus having a blade, the method comprising:

obtaining detection information or prediction information of occurrence of lightning in an installation area of the at least one wind turbine power generating apparatus, prior to lightning strike to the blade; and

switching an operation mode of the at least one wind turbine power generating apparatus to a lightning-protection mode in which a rotor rotation speed is lower than a rated rotation speed so as to prevent the lightning strike on an unexpected portion on the blade of the at least one wind turbine power generating apparatus, on a basis of the detection information or the prediction information of the lightning,

wherein the step of switching the operation mode to the lightning-protection mode includes shifting a state of the at least one wind turbine power generating apparatus to a standby state as the lightning-protection mode in which power generation is stopped without fixing a rotor, and

wherein the lightning-protection mode satisfies at least one of a first condition that the rotor rotation speed of the at least one wind turbine power generating apparatus is 2 rpm or less, or a second condition that a blade tip speed of the at least one wind turbine power generating apparatus is 15 m/s or less.

10. A wind turbine power generation facility, comprising:

a plurality of wind turbines;

a lightning sensor disposed at a location independent of the plurality of wind turbines and configured to detect or predict occurrence of lightning in an installation area of the wind turbines prior to lightning strike to a blade of any one of the wind turbines; and

a controller for outputting a switching command to the plurality of wind turbines to switch an operation mode of the plurality of wind turbines to a lightning-protection mode in which a rotor rotation speed is lower than a rated rotation speed so as to prevent the lightning strike on an unexpected portion on the blade of said any one of the wind turbines, on a basis of an output signal of the lightning sensor.

11. The wind turbine power generation facility according to claim 10 ,

wherein the controller is configured to shift a state of the plurality of wind turbines to a stop state in which a rotor is stopped and power generation is stopped, upon switching to the lightning-protection mode.

12. The wind turbine power generation facility according to claim 11 ,

wherein the plurality of wind turbines is configured to stop the rotor so that all blades are positioned in an azimuth-angular range other than a first angular range of more than 80 degrees and less than 100 degrees, and a second angular range of more than 260 degrees and less than 280 degrees, in the lightning-protection mode.

13. A method of operating a wind turbine power generation facility including a plurality of wind turbines, the method comprising:

obtaining detection information or prediction information of occurrence of lightning in an installation area of the plurality of wind turbines prior to lightning strike to a blade of any one of the wind turbines, by using a lightning sensor disposed at a location independent of the plurality of wind turbines; and

outputting a switching command to the plurality of wind turbines to switch an operation mode of the plurality of wind turbines to a lightning-protection mode in which a rotor rotation speed is lower than a rated rotation speed so as to prevent the lightning strike on an unexpected portion on the blade of said any one of the wind turbines, on a basis of an output signal of the lightning sensor.

14. The method of operating a wind turbine power generation facility according to claim 13 ,

wherein the switching command includes shifting a state of the plurality of wind turbines to a stop state in which a rotor is stopped and power generation is stopped.

15. The method of operating a wind turbine power generation facility according to claim 14 ,

wherein the switching command includes stopping the rotor so that all blades are positioned in an azimuth-angular range other than a first angular range of more than 80 degrees and less than 100 degrees, and a second angular range of more than 260 degrees and less than 280 degrees.