Abstract: Automatic Voltage Control (AVC) system is widely used in wind farms to adjust the voltage at the grid connection point. The control strategy does not fully consider the unit voltage stability of the unit, as well as the coordination and cooperation of multiple reactive power resources within the station, so the problem of the steady-state and transient voltage exceeding limits has not been effectively solved. This paper proposes a coordinated control method of reactive power and voltage for wind farm to improve the voltage stability of the unit. This method optimizes the reactive power and voltage control strategy of wind turbine, so as to ensure that the terminal voltage of the unit is within the normal range and avoid repeated entry and exit voltage crossing mode of the unit. At the same time, the coordinated control strategy of various reactive power compensation devices is optimized to reduce the transient over-voltage level at the generator terminal. An example of a large wind farm with DFIG, SVG and distributed condensers is given to demonstrate the effectiveness of the proposed control method on the ADPSS platform.