WIND FARM AND METHOD FOR OPERATING A WIND FARM

• US 20130175870A1
• Filed: 12/23/2011
• Published: 07/11/2013
• Est. Priority Date: 12/29/2010
• Status: Active Grant

• Current Assignee: Siemens Gamesa Renewable Energy Service GmbH (Siemens AG)
• Original Assignee: Repower Systems SE
• Inventors: Fortmann, Jens
• Granted Patent: US 10,461,536 B2
• Time in Patent Office: Days
• US Class Current: 307/84
• CPC Class Codes: F03D 9/257 the wind motor being part of a wind farm
• CPC Class Codes: F05B 2270/337 Electrical grid status parameters, e.g. voltage, frequency or power demand
• CPC Class Codes: H02J 3/16 by adjustment of reactive power
• CPC Class Codes: H02J 3/18 Arrangements for adjusting, eliminating or compensating reactive power in networks for adjustment of voltage H02J3/16
• CPC Class Codes: Y02E 10/72 Wind turbines with rotation axis in wind direction
• CPC Class Codes: Y02E 10/76 Power conversion electric or electronic aspects
• CPC Class Codes: Y02E 40/30 Reactive power compensation

Abstract

Operating a wind farm in which the power generated by the wind energy installations is fed to a power supply system via a system internal to the wind farm and via a substation is disclosed. The farm director of the wind farm can ascertain a standard target voltage value and transmit it to the control units of the individual wind energy installations on the wind farm, which can use an overall factor to regulate the reactive power generated by a wind energy installation. The overall factor can be calculated from the difference between the actual voltage across the wind energy installation and the target voltage value, multiplied by a gain factor. On account of the impedance in the internal system of the wind farm, wind energy installations situated far away from the substation thus generate less reactive power than the wind energy installations which are situated close to the substation.

Claims

1. A method for operating a wind farm having a plurality of wind energy installations, each having a control unit, which are connected to an internal wind farm network, a substation at which electrical power that is generated on the wind farm is delivered by the internal wind farm network to a power supply network, and a farm master that is connected to the control units of the individual wind energy installations, comprising:

determining, by the farm master, a uniform target voltage value,

transmitting, by the farm master, the target voltage value to the control units of the individual wind energy installations, and

adjusting, by the control unit of the wind energy installation, the reactive power that is generated by a wind energy installation by an overall factor, wherein the overall factor comprises a first factor that is calculated from the difference between the actual voltage present at the wind energy installation and the target voltage value, multiplied by a gain factor.

2. The method of claim 1, wherein the overall factor comprises another factor to be added to the first factor, wherein the factor is calculated from the difference between an actual voltage present at the wind energy installation (10) averaged over a specified period of time and the target voltage value, multiplied by a gain factor.

3. The method of claim 1, wherein the overall factor comprises another factor to be added to the first factor, wherein the factor is calculated from the difference averaged over a specified period of time between the actual voltage present at the wind energy installation and the target voltage value, multiplied by a gain factor.

4. The method of claim 1, wherein the overall factor comprises another factor to be added to the first factor, wherein the factor is calculated from the difference between the actual voltage present at the wind energy installation and the target voltage value averaged over a specified period of time, multiplied by a gain factor.

5. The method of claim 1, wherein the gain factor comprises a global gain factor and an individual gain factor for each wind energy installation.

6. The method of claim 5, wherein one or both of the global gain factor and the individual gain factors is determined by the farm master and is transmitted to the control units of the individual wind energy installations.

7. The method of claim 1, wherein the difference between the actual voltage present at the wind energy installation or the actual voltage present at the wind energy installation averaged over a specified period of time and the target voltage value is reduced by a target voltage correction factor, wherein an individual target value correction factor is provided for each wind energy installation.

8. The method of claim 7, wherein the target voltage correction factor is determined by the farm master and transmitted to the control units of the individual wind energy installations.

9. The method claim 5, wherein at least two wind energy installations are combined into a group, wherein the control units of the wind energy installations in a group are operated using one or both of a shared individual gain factor and target voltage correction factor.

10. A wind farm comprising:

a plurality of wind energy installations, each having a control unit, which are connected to an internal wind farm network,

a substation at which electrical power that is generated on the wind farm is delivered by the internal wind farm network to a power supply network, and

a farm master that is connected to the control units of the wind energy installations,

wherein the farm master is configured to determine a uniform target voltage value and to transmit the target voltage value to the control units of the individual wind energy installations, and the reactive power that is generated by a wind energy installation can be adjusted via the control unit of the wind energy installation by an overall factor, wherein the overall factor comprises a first factor that can be calculated from the difference between the actual voltage present at the wind energy installation and the target voltage value, multiplied by a gain factor.

12. The wind farm of claim 10, characterized in that the overall factor comprises another factor to be added to the first factor, wherein the factor can be calculated from the difference averaged over a specified period of time between the actual voltage present at the wind energy installation and the target voltage value, multiplied by a gain factor.

13. The wind farm of claim 10, wherein the overall factor comprises another factor to be added to the first factor, wherein the factor can be calculated from the difference between the actual voltage present at the wind energy installation and the target voltage value averaged over a specified period of time, multiplied by a gain factor.

14. The wind farm of claims of claim 10, wherein the gain factor comprises a global gain factor and an individual gain factor for each wind energy installation.

15. The wind farm of claim 14, wherein one or both of the global gain factor and the individual gain factors are determined by the farm master and transmitted to the control units of the individual wind energy installations.

16. The wind farm of claim 10, wherein the difference between the actual voltage present at the wind energy installation or the actual voltage present at the wind energy installation averaged over a specified period of time and the target voltage value is reduced via a target voltage correction factor, wherein an individual target voltage correction factor is provided for each wind energy installation.

17. The wind farm of claim 16, wherein the target voltage correction factor is determined by the farm master and transmitted to the control units of the individual wind energy installations.

18. The wind farm of claim 14, wherein at least two wind energy installations are combined into a group, wherein the control units of the wind energy installations in a group are operated using one or both of a shared individual gain factor and target voltage correction factor.

11. The wind farm of claim 19, wherein the overall factor comprises another factor to be added to the first factor, wherein the factor can be calculated from the difference between an actual voltage present at the wind energy installation averaged over a specified period of time and the target voltage value (Utarget), multiplied by a gain factor.