With the widespread use of distributed PV connected into distribution network, three kinds of voltage control strategies are proposed, namely, centralized, decentralized and multi-time scales voltage control. Centralized voltage control adjusts distributed PV, parallel capacitor group and on-load tap changer to optimize voltage control overall the entire network. Decentralized voltage control using local available information, by monitoring point voltage independent control to improve the operation of the grid. Multi-time scale voltage control is composed of long-time scale and short-time scale control in real time. By case study, this paper obtain the advantages and disadvantages of the three voltage control strategies and their application environments, auxiliary planning staff in distribution network make the best decision.