基于电压相位比较的单相接地距离保护方案  

Voltage Phase Comparison Based Single-Phase Grounding Distance Protection Scheme

作　　者：马静 马伟 闫新 刘畅 

机构地区：[1]新能源电力系统国家重点实验室(华北电力大学),北京市昌平区102206 [2]杭州供电公司,浙江省杭州市310009

出　　处：《电网技术》2015年第7期2010-2016,共7页Power System Technology

基　　金：国家重点基础研究发展计划项目(973项目)(2012CB215200);国家自然科学基金项目(51277193)~~

摘　　要：针对过渡电阻引起的距离保护超越或拒动的问题,提出一种基于电压相位比较的单相接地距离保护方案。首先,利用保护安装处负序电流与故障点负序电流相位之间的关系,计算测量电流与故障点电压间的夹角;再以测量电压为参考值,分别计算故障点电压与补偿电压的相角。然后,根据区内与区外故障时故障点电压与补偿电压的相位差异,构造距离保护判据。基于RTDS仿真平台的结果表明,本方案不受过渡电阻和系统运行工况的影响,能够正确判别区内与区外故障;同时,保护动作时间和定值误差满足接地距离保护的技术要求,计算量小,具有较高的工程实用价值。In allusion to the mal-operation or miss operation problems of distance relays caused by the transition resistance, a single-phase grounding distance protection scheme based on voltage phase comparison is proposed. Firstly, in view of the relation between phase of fault negative sequence current at relaying point and that at fault point, the angle between measured current and fault voltage is calculated; then taking the measured voltage as the reference value, the phase angles of the fault voltage and the compensation voltage are calculated respectively. Secondly, operating criterion of distance protection is presented based on the phase difference between fault voltage and compensation voltage during internal fault and external fault. The RTDS based simulation results show that, the proposed scheme is not affected by transition resistance and operation condition, and can discriminate the internal and external fault correctly. Besides, the operation time and setting value error of the proposed scheme meet the requirements of grounding distance protection technology and the small computation amount, therefore it has a great potential practical value.

关 键 词：距离保护 故障点电压 补偿电压 相角 过渡电阻 

分 类 号：TM773[电气工程—电力系统及自动化]