摘要
750 kV输电线绝缘子能承受的过电压裕度较小,因此继电保护及自动重合闸等操作在保证系统稳定的同时,还要确保跳合闸操作不产生危及设备和绝缘子的过电压。针对750 kV输电线路分布参数特性,阐述了空载长线的电容效应及互感效应,并据此提出了线路两端继电保护的跳闸顺序及时间的配合要求。分析了产生重合过电压的原理,对750 kV线路三相重合闸操作进行了可行性分析与比较,指出单相接地故障采用三相重合闸的缺点。在理论研究与电磁暂态程序仿真的基础上,对750 kV线路两端三相重合闸的操作顺序、时间配合提出了具体的三相重合闸方案。仿真测试结果表明,所提出的三相重合闸方案更有利于750 kV输电线路的可靠供电与安全操作。
Considering the characters of distribution parameter, this paper expounds the capacitive effect and asymmetric effect of long transmission line. For 750 kV transmission line with two sources, the tripping operation of relay protections at two terminals of the line should follow certain procedure and its time interval should be within 40 ms-50 ms to avoid insulation damage. Due to the reclosure operation may produce the most serious over-voltage in 750 kV power system, the paper thoroughly analyzes the appearance and characters of three-phase reclosure over-voltage. Research results indicate that the single-phase reclosure can more effectively restraint over-voltage than three-phase reclosure at single-phase faults. Based on the theoretical analysis and Electro Magnetic Transients Program (EMTP) simulation, the paper proposes the specific procedure and time interval of three-phase reclosors at two terminals of the line. Simulation tests show that the presented technique is of benefit to secure operation and power supply of 750 kV transmission line?
出处
《电力系统自动化》
EI
CSCD
北大核心
2004年第12期60-64,共5页
Automation of Electric Power Systems
关键词
超高压输电线
自动重合闸
过电压
继电保护
extra-high voltage transmission line
automatic reclosure
over-voltage
relay protection
