With the increasing permeability of wind farms, the reactive power regulation capability of wind farms based on the fully-rated converted wind turbine can be reasonably considered for the reactive power dispatch of distribution system. Actually, the power grid needs the distributed reactive power source to support the voltage control flexibly and fast, which makes it possible for the wind farms to participate in the automatic voltage control (AVC). This paper proposes an AVC method based on the adaptive zone-division for the distribution system with wind farms. This method has an objective to aptly dispatch the reactive power from wind farms to maintain the voltage stability of the power network. The efficiency of proposed method is validated via a case study on a real power grid of China.