The voltage stability margin of the weak grid is usually insufficient. While the fault ride-through(FRT)performance of the wind farm has significant effect on the transient voltage stability of power grid. The traditional FRT control method for doubly-fed induction generator(DFIG)based wind turbine is on the basis of constant power control which is suitable for strong grid. But it is difficult to support transient voltage stability of the weak grid. Therefore

a new FRT control method for DFIG-based wind turbine is proposed which can be applied to weak grids. The proposed control method based on synchronized control makes the wind turbine operate as controllable voltage source via active current and reactive current droop control. It not only enables the DFIG-based wind turbine to provide active and reactive currents

but also enhances the voltage stability during the transient re-exciting process after grid fault clearance. It is applicable for the DFIG-based wind turbine which needs seamless switching between grid connected and isolated networks as well. The effectiveness and advantages of the proposed control method is validated by the simulation cases of DFIG-based wind turbine connected to infinite bus

practical regional and islanded micro-grid. This work is supported by National Key Research and Development Program of China(No. 2016YFB0900104).