Method for operating a wind energy plant

Patent metadata

Field	Value
Publication number	US-9759193-B2
Application number	US-201314096969-A
Country	US
Kind code	B2
Filing date	Dec 4, 2013
Priority date	Jun 7, 2011
Publication date	Sep 12, 2017
Grant date	Sep 12, 2017

Abstract

The present invention concerns a method of operating a wind power installation comprising a pod with an electric generator for generating electric current and an aerodynamic rotor coupled to the generator and having one or more rotor blades, including the steps: operating the wind power installation when ice accretion on the rotor blades can be certainly excluded, and stopping the wind power installation when ice accretion on the rotor blades is detected, and time-delayed stoppage or prevention of restarting of the wind power installation when an ice accretion was not detected but is to be expected, and/or time-delayed resumption of operation of the wind power installation when a stoppage condition which led to stoppage of the wind power installation has disappeared again and ice accretion was not detected and ice accretion or the formation of an ice accretion is not to be expected.

First claim

The invention claimed is:

1. A method of operating a wind power installation comprising a pod with an electric generator for generating electric current and an aerodynamic rotor coupled to the generator and having one or more rotor blades, the method comprising:
operating the wind power installation when ice accretion on the rotor blades is determined to be excluded;
stopping the wind power installation when ice accretion on the rotor blades is detected; and
time-delayed resuming operation of the wind power installation when a stoppage condition that led to a stoppage of the wind power installation no longer applies and when ice accretion was not detected and ice accretion is determined to not be expected, wherein the time delay starts at a time at which ice accretion is not detected and is not expected,
wherein the stopping of the wind power installation and the resuming operation of the wind power installation depend on a counter,
wherein the counter changes its value at a rate that depends on at least one of the ambient conditions and operating conditions of the wind power installation, and wherein at least one of the following applies:
the counter increases more slowly when the wind power installation operates in a prevailing lighter wind than when it operates in a prevailing stronger wind;
the wind power installation operating in a prevailing lighter wind is stopped after a greater time delay than with a prevailing stronger wind;
the counter decreases more slowly when the wind power installation operates in an ambient temperature that is lower than a threshold value or range than when the ambient temperature is above the threshold value or range; and
the time delay before restarting the wind power installation is shorter when the ambient temperature is above the threshold value or range than when the ambient temperature is below the threshold value or range.

2. The method according to claim 1 wherein resuming operation of the wind power installation depends on an ice predictive indicator that is determined or altered based on a measurement with respect to a probability of ice accretion.

3. The method according to claim 2 , wherein the ice predictive indicator is in the form of a counter and
alters its value in a first direction when at least one of ambient conditions and operating conditions of the wind power installation indicate a possibility of ice accretion; and
alters its value in a second direction when at least one of ambient conditions and operating conditions of the wind power installation indicate that ice accretion is not likely.

4. The method according to claim 1 wherein the wind power installation is coupled to an electric network and is stopped in response to a network failure, and upon network restoration the wind power installation is restarted in dependence on a measurement temperature that depends on a first ambient temperature at a beginning of the network failure and a second ambient temperature upon network restoration.

5. The method according to claim 4 wherein:
the measurement temperature is calculated as a mean value from the ambient temperature at the beginning of the network failure and the ambient temperature upon network restoration if the network failure is not more than a first failure time; and the measurement temperature is calculated as the mean value from the ambient temperature at the beginning of the network failure and the ambient temperature upon network restoration less a temperature safety value if the network failure was longer than the first failure time.

6. The method according to claim 1 wherein the wind power installation is arranged in a wind park and is stopped when at least one further wind power installation of said wind park is stopped due to the detection of ice accretion or the determination that ice accretion is to be expected.

7. The method according to claim 6 wherein the wind power installation that is stopped due to detected ice accretion or suspicion of ice accretion orients its pod in such a way to prevent ice from falling on particular regions therebelow.

8. The method according to claim 1 wherein the wind power installation has a heatable wind sensor for measuring the wind speed, and wherein the wind sensor is heated when at least an ice accretion is detected and an ice accretion cannot be excluded.

9. The method according to claim 1 wherein the wind power installation includes an ice sensor, and ice accretion is detected using the ice sensor.

10. A wind power installation comprising:
a pod with an electric generator for generating electric current;
an aerodynamic rotor coupled to the generator;
one or more rotor blades coupled to the aerodynamic rotor; and
an ice predictor system that includes:
a thermometer for detecting ambient temperature;
a wind speed sensor for detecting wind speed;
a counter that increments or decrements if a combination of ambient temperature and wind speed is above a threshold; and
a computing device coupled to the counter, wherein when the counter increases a consecutive number of times in a row, the computing device outputs a signal indicative of ice accretion being detected, and when the counter decreases a consecutive number of times in a row, the computing device outputs a signal indicating that the ice accretion is no longer detected,

wherein the wind power installation is configured to be operated when the ice predictor system determines that ice accretion on the one or more rotor blades is determined to be excluded,
wherein the wind power installation is configured to be stopped when the ice predictor system determines that ice accretion on the one or more rotor blades is detected,
wherein the wind power installation is configured to resume operation after a time-delay when a stoppage condition that led to a stoppage of the wind power installation no longer applies and when ice accretion is not detected and ice accretion is determined to not be expected, wherein the time delay starts at a time at which ice accretion is not detected and is not expected,
wherein the stopping of the wind power installation and the resuming operation of the wind power installation depend on the counter,
wherein the counter is configured to change its value at a rate that depends on at least one of the ambient conditions and operating conditions of the wind power installation, and wherein at least one of the following applies:
the counter is configured to increase more slowly when the wind power installation operates in a prevailing lighter wind than when it operates in a prevailing stronger wind;
the wind power installation when operating in a prevailing lighter wind is configured to be stopped after a greater time delay than with a prevailing stronger wind;
the counter is configured to decrease more slowly when the wind power installation operates in an ambient temperature that is lower than a threshold value or range than when the ambient temperature is above the threshold value or range; and
the time delay before restarting the wind power installation is shorter when the ambient temperature is above the threshold value or range than when the ambient temperature is below the threshold value or range.

11. The wind power installation of claim 10 further comprising control electronics, wherein the computing device outputs the signal indicative of the possibility of ice accretion, the control electronics generates a signal to stop the operation of the wind power installation.

12. The wind power installation of claim 11 wherein the computing devices delays outputting the signal indicating that the possibility of ice accretion no longer applies for a period of t

Assignees

• Wobben Properties Gmbh

Inventors

• Jepsen Torsten

Classifications

• F03D7/026

  for starting-up · CPC title

• F05B2270/303

  Temperature · CPC title

• F03D80/40

  Ice detection; De-icing means · CPC title

• F03D7/0264 Primary

  for stopping; controlling in emergency situations (orientating out of wind F03D7/0208) · CPC title

• F05B2270/325

  Air temperature · CPC title