To the problem of low voltage ride through of the permanent magnetive synchronous offshore wind power, a control scheme based on energy storage and reactive power optimization is proposed for the DC link overvoltage problem in the unit grid-connected system. Taking distributed energy storage equipment, using the charging and discharging characteristics of the battery, the superfluous power of the DC bus can be absorbed when takes place a fault. The the active power output of the grid side converter, the DC bus voltage and the generator terminal voltage as the evaluation indexes, the low voltage ride through ability of each unit in the wind farm is evaluated to optimize the control of energy storage and reactive power output of each unit. The DC voltage rise of the unit is effectively suppressed when the grid fault occurs, and the grid voltage is supported. An offshore wind power farm as an example, the simulation results show that this scheme can significantly improve the low voltage ride-through capability of wind farm.