[Introduction] The control and protection technology of DC microgrid plays an important role in ensuring the reliable and safe operation of DC microgrid. The paper aims to solve the key technologies in the design of DC micro-grid. [Method] DC bus topology selection, control strategy, and protection configuration scheme were discussed in the paper. [Result] The selection principle of DC bus topology structure, the control strategy process of DC micro-grid, protection zone and configuration are given in the paper. At the same time, the selection of DC transformer is analyzed and compared. [Conclusion] The method has been validated in national demonstration projects, and it has performed well since it was put into operation.
