WO/2004/040748 is referenced by 13 patents.

A circuit arrangement in a grid-connected variable speed wind turbine system comprising a double-fed induction generator (G) connected on the stator side to the grid and on the rotor side to a back-to-back converter connected for transferring energy between the rotor of the double-fed induction generator (G) and the grid, is provided with means (S2) for disconnecting at least one normally grid-connected terminal of the back-to-back converter from the grid and means (S1) for connecting an impedance for allowing controlled power transfer from the intermediate DC circuit to said impedance. The control is performed by one or more power-switching elements of the normally grid-connected converter (GC), which has been disconnected from the grid. This makes it possible to keep the generator (G) connected to the grid during grid faults and take active part in the reestablishment of the grid voltage.

Title
Circuit arrangement for use in a variable speed wind turbine system comprising a double-fed induction generator and a back-to-back converter
Application Number
PCT/DK2002/000729
Publication Number
2004/040748
Application Date
November 1, 2002
Publication Date
May 13, 2004
Inventor
Nielsen John Godsk
Agent
BUDDE SCHOU Vester Søgade 10 DK 1601 København
Assignee
Nielsen John Godsk
Vestas Wind Systems
IPC
H02P 09/42
H02P 09/00
F03D 09/00
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