Abstract: In a high proportion of new energy power grid, wind turbine off grid accidents caused by system faults occur from time to time. It is very important to enhance the fault ride through ability of wind turbine and reduce the off grid frequency for the stable operation of power grid. Based on the analysis of the vector control principle of converter, it is oretically concluded that the transient overvoltage of power grid is easy to cause the converter on the grid side to reach the upper limit of its AC voltage regulation, resulting in AC / DC power coupling oscillation and causing instability or overvoltage trip protection. In this paper, based on the requirements of relevant standards, the (HVRT) transient optimal control was established. By increasing the reactive power support, the filter inductor was used to mitigate the overvoltage impact. It not only met the requirements of voltage vector control of the converter, but also increased the reactive current injected into the grid, which was conducive to voltage recovery. The improved control adopted subsection optimization was designed according to different voltages in order to improve the reactive power support and the upper limit of ride through voltage, and energy storage was added to the DC side. The theoretical analysis based on typical parameters and the simulation experiment based on MATLAB/Simulink proved the correctness of the fault characteristic analysis and transient optimal control.