Method and system for monitoring an individual blade adjustment of a wind turbine

Patent metadata

Field	Value
Publication number	US-10167848-B2
Application number	US-201514852581-A
Country	US
Kind code	B2
Filing date	Sep 13, 2015
Priority date	Mar 14, 2013
Publication date	Jan 1, 2019
Grant date	Jan 1, 2019

Abstract

The invention relates to a method and a system for monitoring an individual blade adjustment of a wind turbine which includes a tower, a rotor which is arranged on the tower and has at least two rotor blades whose blade angle can be adjusted individually, and a blade adjustment system, wherein the blade adjustment system includes a blade controller and sensors for sensing individual actual blade angles of the at least two rotor blades, wherein an individual blade controller is included which receives a collective set point blade angle from the blade controller and which actuates at least two rotor blades with respectively individual set point blade angles, as well as a corresponding wind turbine.

First claim

What is claimed is:

1. A method for operating a wind turbine that includes
a tower,
a rotor arranged on the tower having at least two rotor blades, wherein of each of said at least two rotor blades has an individually adjustable blade angle,
a blade adjustment system that includes a blade controller and sensors for sensing individual actual blade angles θ i act of the at least two rotor blades, and
an individual blade controller configured to receive a collective set point blade angle θ c set from the blade controller and to actuate the at least two rotor blades with individual set point blade angles θ i IPC , respectively,

the method comprising:
forming a difference signal based upon a difference between
(a) a collective blade angle actual mean value θ act and a collective blade angle set point mean value θ IPC ;
(b) the collective set point mean value θ IPC and the collective set point blade angle θ c set ; or
(c) the collective set point blade angle θ c set and a collective actual mean value θ act ;

averaging the difference signal over time to obtain an averaged over time value;
monitoring the averaged over time value to determine whether at least one limiting value is exceeded in absolute terms; and
reducing an operation of the wind turbine with respect to load when the averaged over time value exceeds the at least one limiting value in absolute terms and determining a malfunction of:
(i) a blade adjustment drive or a blade bearing where the difference signal is based upon the difference between (a) the collective blade angle actual mean value θ act and the collective blade angle set point mean value θ IPC ; or
(ii) the individual blade controller where the difference signal is based upon the difference between either (b) the collective set point mean value θ IPC and the collective set point blade angle θ c set or (c) the collective set point blade angle θ c set and the collective actual mean value θ act .

2. The method according to claim 1 , wherein in order to calculate the set point mean value θ IPC , averaging is carried out over the individual set point blade angles θ i IPC of the individual blade controller or a response of the blade adjustment system to the requested individual set point blade angles θ i IPC is simulated, and averaging is carried out over the simulated individual blade angles θ i sim of the simulated blade adjustment system.

3. The method according to claim 1 , wherein in order to calculate the set point mean value θ IPC , averaging is carried out over the individual set point blade angles θ i IPC of the individual blade controller and a response of the blade adjustment system to the requested individual set point blade angles θ i IPC is simulated, and averaging is carried out over the simulated individual blade angles θ i sim of the simulated blade adjustment system.

4. The method according to claim 1 , wherein the averaging over time is carried out over an averaging duration which is less than a duration of half a rotor revolution.

5. The method according to claim 4 , wherein the duration is between 0.5 seconds and 2 seconds.

6. A system for operating a wind turbine that includes
a tower,
a rotor arranged on the tower having at least two rotor blades, wherein of each of said at least two rotor blades has an individually adjustable blade angle,
a blade adjustment system that includes a blade controller and sensors for sensing individual actual blade angles θ i act of the at least two rotor blades, and
an individual blade controller configured to receive a collective set point blade angle θ c set from the blade controller and to actuate the at least two rotor blades with individual set point blade angles θ i IPC , respectively,

said system comprising a monitoring device configured to:
form a difference signal based upon a difference between
(a) a collective blade angle actual mean value θ act and a collective blade angle set point mean value θ IPC ;
(b) the collective set point mean value θ IPC and the collective set point blade angle θ c set ; or
(c) the collective set point blade angle θ c set and a collective actual mean value θ act ;

average the difference signal over time to obtain an averaged over time value;
monitor the averaged over time value to determine whether at least one limiting value is exceeded in absolute terms; and
reduce an operation of the wind turbine with respect to load when the averaged over time value exceeds the at least one limiting value in absolute terms and determine a malfunction of:
(i) a blade adjustment drive or a blade bearing where the difference signal is based upon the difference between (a) the collective blade angle actual mean value θ act and the collective blade angle set point mean value θ IPC ; or
(ii) the individual blade controller where the difference signal is based upon the difference between either (b) the collective set point mean value θ IPC and the collective set point blade angle θ c set or (c) the collective set point blade angle θ c set and the collective actual mean value θ act .

7. The system according to claim 6 , wherein the monitoring device is integrated into an operational control system or into the blade adjustment system of the wind turbine.

8. A wind turbine comprising:
a tower;
a rotor arranged on the tower having at least two rotor blades, wherein of each of said at least two rotor blades has an individually adjustable blade angle;
a blade adjustment system that includes a blade controller and sensors for sensing individual actual blade angles θ i act of the at least two rotor blades;
an individual blade controller configured to receive a collective set point blade angle θ c set from the blade controller and to actuate the at least two rotor blades with individual set point blade angles θ i IPC , respectively; and
a system for operating a wind turbine according to claim 6 .

9. A system for monitoring an individual blade adjustment of a wind turbine that includes
a tower,
a rotor arranged on the tower having at least two rotor blades, wherein of each of said at least two rotor blades has an individually adjustable blade angle,
a blade adjustment system that includes a blade controller and sensors for sensing individual actual blade angles θ i act of the at least two rotor blades, and
an individual blade controller configured to receive a collective set point blade angle θ c set from the blade controller and to actuate the at least two rotor blades with individual set point blade angles θ i IPC , respectively,

wherein the system comprises:
a monitoring device configured to:
form a difference signal based upon a difference between
(a) a collective blade angle actual mean value θ act and a collective blade angle set point mean value θ IPC ;
(b) the collective set point mean value θ IPC and the collective set point blade angle θ c set ; or
(c) the collective set point blade angle θ c set and a collective actual mean value θ act ;

average the difference signal over time to obtain an averaged over time value; and
monitor the averaged over time value to determine whether at least one limiting value is exceeded in absolute terms; and

means configured to carry out a method according to claim 1 .

Assignees

• Senvion Gmbh

Inventors

• Warfen Karsten
• Hendus Lothar
• Bilges Sören
• Leweke Henning

Classifications

• F03D17/00

  Monitoring or testing of wind motors, e.g. diagnostics (testing during commissioning of wind motors F03D13/30) · CPC title

• F05B2270/328

  Blade pitch angle · CPC title

• F03D7/0224 Primary

  Adjusting blade pitch · CPC title

• Y02E10/721

  Cross-Sectional Technologies · mapped topic

• Y02E10/723

  Cross-Sectional Technologies · mapped topic