文档介绍：IEEE TRANSACTIONS ON ENERGY CONVERSION, VOL. 20, NO. 2, JUNE 2005
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Ridethrough of Wind Turbines with Doubly-Fed Induction Generator During a Voltage Dip
Johan Morren, Student Member, IEEE, and Sjoerd W. H. de Haan, Member, IEEE
Abstract—In this paper, a solution is described that makes it pos-sible for wind turbines using doubly-fed induction generators to stay connected to the grid during grid faults. The key of the solution is to limit the high current in the rotor in order to protect the con-verter and to provide a bypass for this current via a set of resistors that are connected to the rotor windings. With these resistors, it is possible to ride through grid faults without disconnecting the tur-bine from the grid. Because the generator and converter stay con-nected, the synchronism of operation remains established during and after the fault and normal operation can be continued imme-diately after the fault has been cleared. An additional feature is that reactive power can be supplied to the grid during long dips in order to facilitate voltage restoration. A control strategy has been developed that takes care of the transition back to normal opera-tion. Without special control action, large transients would occur.
Index Terms—Doubly-fed induction generator (DFIG), protec-tion, wind power generation.
I. INTRODUCTION
THE worldwide concern about the environment has le