摘要
传统直流微电网的差动保护需要考虑区内故障和区外故障,不易于系统识别高电阻故障,且直流微电网不仅可与交流电网并网,还可以孤岛运行,其保护方案相对复杂。为克服此类缺点,研究直流微电网的双斜率电流差动保护方案,通过分析高阻故障和低阻故障的电流变化情况且判断延时时间,实现对高阻故障的检测。基于采集电流信息获知故障位置,故障发生时可以快速切除,确保电网的稳定运行。最后通过PSCAD进行仿真分析,结果显示所提出的电流差动保护方案能够准确识别线路内的高阻故障和低阻故障,从而提高直流微电网的供电可靠性。
DC microgrid technology is an emerging technology that has been developed in recent years and is also connected to the power grid. However,the protection and control of its operation has always been a difficult point of research. The DC microgrid can not only be connected to the AC grid,but also can be operated on an island. The protection scheme is relatively complicated. In this paper,the current differential protection scheme of DC microgrid is studied. The fault location is obtained based on the collected current information. When the fault occurs,it can be quickly cut off to ensure the stable operation of the grid. By constructing the model,performing simulation analysis,verifying the feasibility of the protection scheme,and improving the reliability of the power supply of the DC microgrid.
作者
李国军
曹瀚元
LI Guo-jun;CAO Han-yuan(School of Automation,Nanjing University of Science and Technology,Nanjing 210094,China;Equipment Department,Nanjing United Rongda Engineering Materials Co.,Ltd.,Nanjing 211163, China)
出处
《电子设计工程》
2019年第20期128-132,共5页
Electronic Design Engineering
关键词
直流微电网
电流差动保护
高阻故障
实验仿真
DC microgrid
Current differential protection
High resistance fault
Experimental simulation
