With the development of distributed generation and power electronic technology

DC distribution network based on voltage source converter(VSC)has many advantages

such as flexible access

high reliability and good economic efficiency. Based on the detailed analysis of the VSC steady-state power flow model

the power flow calculation of multi-terminal DC distribution network is studied through taking into account the operation control strategy of the DC distribution network. In the process of power flow calculation

it uses the node correlation matrix to search automatically the network structure and open automatically the looped network. It proposes a unified power correction method for looped network and droop node

and takes into account the power limitation and control mode conversion of VSC. With the modified IEEE 14-node DC distribution example system

it verifies the correctness and validity of the proposed power flow calculation method.