摘要
基于单相接地模型,推导得到由故障点两侧零序阻抗角差异引起测量电抗的综合误差,根据综合误差的具体情况对测量电抗进行补偿,从而得到自适应接地距离继电器动作判据。新判据的多边形阻抗特性用纯电抗线来代替传统的电抗下倾线,不再像传统距离保护那样盲目地缩小动作范围。在可靠防止距离保护超越误动作的前提下,扩大了距离保护的动作范围。用EMTP进行了大量的数字仿真实验,结果表明,自适应阻抗动作判据能有效防止保护超越误动作,也提高了区内故障的动作灵敏度。
Based on case of single-phase-to-ground fault, this paper derives the combined error of measured reactance in proportion to the distance to the fault, and provides a new adaptive impedance criterion through error correction. A new reactance line in the polygon impedance characteristic of the proposed criterion is suggested to replace the declinational reactance line. This does not need to reduce the protection zone any more as conventional way to prevent the relay from overreaching. The protection zone of the proposed distance relay is greatly increased without any danger of real-operation. The performance of the relay is extensively tested by using EMTP. The simulation results show that the relay can be used to avoid transient overreaching effectively and has high sensitivity for the internal fault.
出处
《电力系统自动化》
EI
CSCD
北大核心
2005年第17期54-58,共5页
Automation of Electric Power Systems
基金
教育部博士学科点基金资助项目(20010698015)~~
关键词
电力系统
继电保护
距离继电器
过渡电阻
power systems
protective relaying
distance relay
fault resistance
