摘要
现有小电阻接地系统各级接地保护定值过高,在高阻接地时保护易拒动,利用反时限零序过电流保护可以提高保护灵敏度,但为实现选择性各级保护需要重新配置与整定。分析了不同位置经不同过渡电阻接地时,故障点、各出线、分支线及中性点上零序电流的分布规律。利用上下级保护之间的纵向配合及同级保护之间的横向配合,提出一种基于反时限零序过电流保护原理的小电阻接地系统高灵敏度接地保护配置方案,给出了各级保护的整定原则。仿真验证了所提接地保护整定原则的可行性与可靠性。
The setting value of the existing grounding fault protection for a low-resistance grounding system at all levels is too high to protect the system from high-impedance grounding faults.Although the zero-sequence inverse-time over current protection can improve the protection sensitivity,it needs to be reconfigured and tuned to achieve selective pro tection at all levels.When a grounding fault occurs at different positions by different transition resistances,the distribu tion laws of zero-sequence current at the fault point,on each main line and branch line,and at the neutral point are ana lyzed.With the help of the longitudinal cooperation between the upper and lower protections,as well as the lateral coop eration between protections at the same level,a configuration scheme for high-sensitivity grounding fault protection is proposed based on the zero-sequence inverse-time overcurrent protection principle.In addition,the tuning principle for protection at all levels is given.Simulation results verify the feasibility and reliability of the proposed grounding fault protection tuning principle.
作者
林志超
汪洋
罗步升
薛永端
王英民
王敬华
LIN Zhichao;WANG Yang;LUO Busheng;XUE Yongduan;WANG Yingmin;WANG Jinghua(Huizhou Power Supply Bureau,Guangdong Power Grid Co.,Ltd,Huizhou 516001,China;College of Information and Control Engineering,China University of Petroleum(East China),Qingdao 266580,China;Shandong Kehui Electric Automation Co.,Ltd,Zibo 255087,China)
出处
《电力系统及其自动化学报》
CSCD
北大核心
2020年第3期25-32,共8页
Proceedings of the CSU-EPSA
基金
国家自然科学基金资助项目(51477184)
广东电网有限责任公司科技项目(031300KK52160025)。
关键词
小电阻接地系统
高阻接地
接地保护
反时限零序过电流保护
配置与整定
low-resistance grounding system
high-impedance grounding
grounding fault protection
zero-sequence in verse-time overcurrent protection
configuration and tuning
