Controller and control method for a wind turbine

Patent metadata

Field	Value
Publication number	US-2022010772-A1
Application number	US-201917295320-A
Country	US
Kind code	A1
Filing date	Nov 22, 2019
Priority date	Nov 23, 2018
Publication date	Jan 13, 2022
Grant date	—

Abstract

A controller structure for a wind turbine having an aerodynamic rotor with at least one rotor blade, wherein the controller structure is designed to control a rotation speed of the rotor of the wind turbine, wherein the controller structure is designed as a cascade control arrangement and has an outer control loop and an inner control loop, wherein the inner control loop receives an input signal which comprises a change in the rotation speed, an acceleration of the rotation speed, a function of the change in the rotation speed and/or a function of the acceleration of the rotation speed.

First claim

1 . A controller for a wind turbine having an aerodynamic rotor with at least one rotor blade, the controller comprising:
circuitry forming a cascade control arrangement and having an outer control loop and an inner control loop, wherein the controller is configured to control a rotation speed of the aerodynamic rotor of the wind turbine, wherein the inner control loop is configured to receive one or more input signals indicative of one or more characteristics chose from a change in the rotation speed, an acceleration of the rotation speed, a function of a change in the rotation speed and a function of an acceleration of the rotation speed.

2 . The controller as claimed in claim 1 , wherein a controlled variable of the outer control loop is provided as a reference variable of the inner control loop.

3 . The controller as claimed in claim 2 , wherein the outer control loop is configured to limit a target value of the inner control loop, wherein the target value is at least one value chose among a change in the rotation speed, the acceleration of the rotation speed, the function of the change in the rotation speed, and the function of the acceleration of the rotation speed.

4 . The controller as claimed in claim 1 , wherein:
the one or more input signals received by the inner control loop comprises a rotor acceleration power or a rotor acceleration torque, and the rotor acceleration power or the rotor acceleration torque describes a portion of a power or torque received by the aerodynamic rotor of the wind turbine that is converted into an acceleration of the aerodynamic rotor.

5 . The controller as claimed in claim 1 , wherein:
the one or more input signals received by the inner control loop comprises an aerodynamic power received by the aerodynamic rotor, the aerodynamic power comprises a sum of a rotor acceleration power and a generator power of a generator of the wind turbine, and the rotor acceleration power describes a portion of a power received by the aerodynamic rotor of the wind turbine that is converted into an acceleration of the aerodynamic rotor.

6 . The controller as claimed in claim 1 , wherein the outer control loop determines a deviation of an actual rotation speed of the aerodynamic rotor from a target rotation speed of the aerodynamic rotor as a system deviation.

7 . The controller as claimed in claim 1 , wherein the outer control loop generates a target value of a power or of a torque as manipulated variable.

8 . The controller as claimed in claim 7 , wherein the target value of the power is limited by an upper limit and a lower limit.

9 . The controller as claimed in claim 8 , wherein the target value of the power is asymmetrically limited by the upper limit and the lower limit.

10 . The controller as claimed in claim 7 , wherein the power comprises a rotor acceleration power,
wherein the rotor acceleration power is limited to a rated power of the wind turbine, wherein the rotor acceleration power is 20% of the rated power of the wind turbine or less.

11 . The controller as claimed in claim 7 , wherein the power comprises an aerodynamic rotor power,
wherein the aerodynamic rotor power is limited to twice a rated power of the wind turbine.

12 . The controller as claimed in claim 1 , wherein the inner control loop generates, as manipulated variable, a pitch angle or a rate of change in a pitch angle of at least one of the rotor blades of the aerodynamic rotor.

13 . The controller as claimed in claim 12 , wherein the target value for the rate of change in the pitch angle is limited to a value of between −18°/second and 18°/second.

14 . The controller as claimed in claim 1 , wherein at least one control loop chosen from the outer control loop and the inner control loop forms a Proportional (P) controller or a Proportional and Integral (PI) controller.

15 . The controller structure as claimed in claim 1 , further comprising a calculation circuitry configured to determine a rotor acceleration power from a change in a measured actual rotation speed of the wind turbine using an inertia of the aerodynamic rotor.

16 . The controller as claimed in claim 1 , further comprising a pilot control arrangement for pilot control of a pitch angle of the at least one rotor blade, wherein the pilot control arrangement is configured to prespecify, parallel to the inner control loop, at least one characteristic chose among a pitch angle and a rate of change in the pitch angle.

17 . A method comprising:
operating a wind turbine having an aerodynamic rotor with at least one rotor blade, wherein the operating comprises controlling a rotation speed of the rotor of the wind turbine, wherein the controlling comprises using a cascade control arrangement having an outer control loop and an inner control loop, wherein the controlling comprising: acquiring, by the inner control loop, an input signal indicative of one or more characteristics chosen from a change in the rotation speed, an acceleration of the rotation speed, a function of a change in the rotation speed and a function of an acceleration of the rotation speed.

18 . A wind turbine comprising the controller as claimed in claim 1 .

19 . A wind farm comprising a plurality of wind turbines as claimed in claim 18 .

Assignees

• Wobben Properties Gmbh

Inventors

• Von Aswege Enno

Classifications

• F05B2270/101

  to control rotational speed (n) · CPC title

• F05B2270/335

  Output power or torque · CPC title

• F03D7/0224

  Adjusting blade pitch · CPC title

• F05B2270/327

  Rotor or generator speeds · CPC title

• F05B2270/309

  Rate of change of parameters · CPC title