Inrush current protection for wind turbines and wind farms

Patent metadata

Field	Value
Publication number	US-9745959-B2
Application number	US-201313951786-A
Country	US
Kind code	B2
Filing date	Jul 26, 2013
Priority date	Sep 16, 2011
Publication date	Aug 29, 2017
Grant date	Aug 29, 2017

Abstract

A wind turbine is provided. The wind turbine includes a transformer having a low-voltage side and a high-voltage side. The transformer is configured to step up a voltage of the low-voltage side of the transformer to a voltage of an external grid. The wind turbine further includes an electrical power generating unit which is connected to the low-voltage side of the transformer and configured to feed an ac-power to the low-voltage side of the transformer. A charging device of the wind turbine is connected to the low-voltage side of the transformer and configured to charge the low-voltage side of the transformer when the generator does not feed ac-power to the low-voltage side of the transformer.

First claim

What is claimed is:

1. A wind turbine comprising:
a transformer comprising a low-voltage side and a high-voltage side and configured to step up a low voltage at the low-voltage side to a high voltage of an external grid;
an electrical power generating unit connected to the low-voltage side of the transformer and configured to feed an ac-power to the low-voltage side of the transformer; and
a charging device connected to the low-voltage side of the transformer and configured to charge the low-voltage side of the transformer with energy buffered from the external grid when the electrical power generating unit does not feed ac-power to the low-voltage side of the transformer.

2. The wind turbine of claim 1 , further comprising a switch connected between the external grid and the high-voltage side of the transformer and configured to open and close a connection between the high-voltage side of the transformer and the external grid.

3. The wind turbine of claim 2 , wherein the charging device is configured to cause closing the switch after a voltage of the low-voltage side of the transformer has reached a predefined value.

4. The wind turbine of claim 2 , wherein the charging device comprises a controller connected to the switch and configured to issue closing the switch.

5. The wind turbine of claim 2 , further comprising a voltage switchgear comprising the switch and a voltage transformer comprising a high-voltage side connected to the external grid and a low voltage side, wherein the charging device is connected to the low voltage side of the voltage transformer.

6. The wind turbine of claim 1 , wherein the charging device comprises an inverter connected to the low-voltage side of the transformer and configured to output at least one rising ac output-signal to the low-voltage side of the transformer.

7. The wind turbine of claim 6 , wherein the inverter is configured to ramp the at least one rising ac output-signal substantially to a rated voltage of the electrical power generating unit.

8. The wind turbine of claim 6 , wherein the charging device comprises an energy buffer connected to the inverter, the energy buffer being chargeable with a power of the external grid.

9. The wind turbine of claim 6 , wherein the charging device comprises a controller which is configured to detect a recovery of the external grid and to control the inverter such that the at least one rising ac output-signal is substantially in phase with the external grid.

10. The wind turbine of claim 6 , further comprising a sensor connected to the external grid and a controller connected to the sensor and configured to control the inverter such that at least one rising ac output-signal is substantially in phase with the external grid.

11. A wind turbine comprising:
a transformer comprising a low-voltage side and a high-voltage side and configured to step up a low voltage at the low-voltage side to a high voltage of an external grid;
an electrical power generating unit connected to the low-voltage side of the transformer and configured to feed an ac-power to the low-voltage side of the transformer;
a charging device connected to the low-voltage side of the transformer and configured to charge the low-voltage side of the transformer when the electrical power generating unit does not feed ac-power to the low-voltage side of the transformer; and
a voltage switchgear comprising a switch connected between the external grid and the high-voltage side of the transformer and configured to open and close a connection between the high-voltage side of the transformer and the external grid, the voltage switchgear further comprising a voltage transformer comprising a high-voltage side connected to the external grid and a low voltage side connected to the low voltage side of the voltage transformer.

Assignees

• Gen Electric

Inventors

• Langel Andre

Classifications

• F05B2270/1071

  in particular sudden load loss · CPC title

• F03D9/11

  storing electrical energy · CPC title

• F05B2270/10711

  applying a low voltage ride through method · CPC title

• F03D9/255

  connected to electrical distribution networks; Arrangements therefor · CPC title

• H02J9/06

  with automatic change-over {, e.g. UPS systems} · CPC title