Modeling and control of a wind-turbine-drive DFIG during grid voltage dips based on DIgSILENT/PowerFactory

The low voltage ride through (LVRT) capability of DFIG has caused more concern. And for testing requirements of LVRT for DFIG WT, this paper propose control strategies for LVRT of DFIG WTs by injecting reactive power into grid. Reactive power allocation are decided by voltage sag levels. When grid voltage drop to 30%, grid-side converter (GSC) works as a STATCOM. Their maximum limited reactive current expressions are also considered. An active power control strategy is proposed considering the recovery rate requirement of the active power. Furthermore, a novel RMS model is presented based on external characteristics. Simulations on a 2.5MW DFIG wind turbine demonstrate that the output characteristics satisfy requirement of grid code of wind power.