中低压直流配电系统的发展对区域性电能传输,提高新能源的普及率,提高交直流互联电网的运行安全性具有重要意义.本文首先总结了许多国家提出的中低压直流配电系统方案和计划,然后详细阐述了中国在建的中低压直流配电系统项目案例的现状. 基于这些工程案例,本文分析了中低压直流配电系统的拓扑结构,设备,运行控制技术和直流故障保护等关键问题,为今后中低压直流配电系统相关项目提供理论和技术参考.最后,本文结合中国当前的研究现状,对中低压直流配电系统的未来研究方向进行了总结和预测,为中低压直流配电系统的研究提供参考.“,”Development of the medium and low voltage DC distribution system is of great significance to a regional transmission of electric energy, increasing a penetration rate of new energy, and enhancing a safety of the operation of the AC/DC interconnected grid. This paper first summarizes the medium and low voltage DC distribution system schemes and plans put forward by many countries, and then elaborate status of under-construction medium and low voltage DC distribution system project cases in China. Based on these project cases, this paper analyzes key issues involved in the medium and low voltage DC distribution system topologies, equipment, operation control technologies and DC fault protections, in order to provide theoretical and technical reference for future medium and low voltage DC distribution system-related projects. Finally, this paper combines a current China research status to summarize and give a prediction about the future research direction of medium and low voltage DC distribution system, which can provide reference for the research of medium and low voltage DC distribution system.