With the increasingly installed capacity of wind power

it is important to take focus of the faults in the grid side of wind power which will cases transient state characteristic. A direct-drive permanent magnet wind turbine with doubly-fed induction wind dynamic model of wind turbines is built by using PSCAD software

and the influence of the two models on transient stability of power grid is discussed.Two kinds of LVRT results are discussed which including symmetrical faults and asymmetric faults occurring in the wind under

as well as the installation of reactive power compensation device in low voltage after the wind farm through the ability. The wind generator simulation analysis to compare active power、reactive power and dc voltage came to the following conclusions: although double-fed induction wind power generator can improve low voltage by series of braking resistor across ability

after the failure of eliminating the grid voltage mutation has certain influence to the doubly-fed machine

the strong dependence of power grids. In order to optimize the power quality

a direct-drive permanent magnet wind turbine in the power grid failure due to its structure having good running characteristics.Wind farms in different wind turbines should adopt different strategies to improve the stability of power grid.