Abstract: Distributed generation（DG） is emerging in a large number these years,but its layout is not uniform,which makes the distribution of source and load unbalanced among different power consumption areas and DG unable to be absorbed effectively. Therefore, this paper proposes the structure of flexible interconnected distribution network with embedded DC system to realize feeder terminal interconnection,so as to achieve the purpose of power allocation between different areas and high permeability distributed power consumption. Firstly,the mathematical model of the proposed system is established, including AC system, DC system,Modular Multi-level Converter（MMC）and small signal global model of the control link. Secondly,the root locus of the model is analyzed by MATLAB,and the selection range of some control parameters is given. Finally,the system is built based on PSCAD and electromagnetic transient simulation is carried out.The running images of MATLAB and PSCAD in different scenes are compared to verify the accuracy of the mathematical model.