中文摘要：

随着新能源的推广和直流负荷的普及,直流微网作为分布式电源更有效率的接入形式,受到了越来越多的关注,而继电保护技术是直流微网发展的关键技术之一,该文旨在系统地介绍国内外直流微网保护技术的研究状况。文章介绍直流领域多种保护设备的发展现状,总结直流微网接地形式的研究成果,针对直流故障电容快速放电、电力电子器件耐故障过电流能力弱的问题,比较多种快速切断或限制故障电流的方案,在此基础上,对各种保护配置方案进行分析和评价,最后给出直流微网保护未来研究方向的展望,并提供关键问题的解决思路。

英文摘要：

With the promotion of new energy resources and popularization of DC loads, DC microgrid which is more efficient for distributed generation to access receives more and more attentions, and relay protection is one of the key technologies for the development of DC microgrid. This paper aimed to systematically introduce the research situation about the protection technology for DC microgrid system at home and abroad. The development status of a variety of protection devices used in DC system was presented, and research results for DC grounding type were summarized. Considering that the DC-Link capacitor discharges instantly and power electronic devices were vulnerable to the high fault current, various schemes about quickly cutting off or limiting the fault current were compared. On this basis, various protection schemes were discussed and analyzed. Finally, this study identified the future trends and provided solutions to key issues in the field of protections of DC microgrid.