The high reliability power supply and friendly access to large-scale distributed power promotes the closed loop operation of active distribution network. To satisfy the safety and economic requirements of closed loop operation and make full use of clean energy

the safe closed loop operation and power flow optimization control method of distribution network based on back-to-back VSC-HVDC is studied. By analyzing the injected power model and control method of large-scale distributed power supply and referring to the distribution loop system

we make the minimum integrated cost of power supply enterprises the objective and build the active distribution loop optimization operation model

with the network power flow

distributed energy output

VSC-HVDC power balance

etc as the constraints. Based on an improved IEEE 33-node system

simulation examples of various operation modes have verified that the back-to-back VSC-HVDC can attain the goal of safe closed loop operation of distribution network

economical distribution of power loop and full use of large-scale distributed power supply.