Aiming at the significant differences between operating characteristics, reactive voltage characteristics and traditional distribution networks after the introduction of a large number of distributed power sources in the distribution network, an automatic voltage control system architecture of active distribution network based on distribution automation system is proposed. Based on the real-time topology connection of feeders, an autonomous control region division method with reactive power adjustable device as the control object is proposed, including: voltage control partition strategy, voltage over-limit control strategy, feeder reactive over-limit control strategy, coordinated control strategy with other systems and safety blocking strategy. Then, a voltage and reactive power control strategy based on autonomous control region is designed, and the overall flow of the automatic voltage control system for distribution network is given. Finally, combined with the actual case, the active distribution network automatic voltage control system architecture described in this paper is a useful exploration of voltage reactive power control at the level of distribution automation system.