超、特高压交流线路反时限零序过流后备保护的整定建议  

Setting suggestions of inverse-time zero-sequence overcurrent backup protection for EHV and UHV AC lines

作　　者：刘阳 陈祥文 王玉龙[3] 李会新 李勇 王英英 LIU Yang;CHEN Xiangwen;WANG Yulong;LI Huixin;LI Yong;WANG Yingying(Central China Branch of State Grid Corporation of China,Wuhan 430077,China;Lamor Innovation Studio of Liu Huanzhang,Wuhan 430077,China;NR Electric Co.,Ltd.,Nanjing 211102,China)

机构地区：[1]国家电网有限公司华中分部,湖北武汉430077 [2]柳焕章劳模创新工作室,湖北武汉430077 [3]南京南瑞继保电气有限公司,江苏南京211102

出　　处：《电力自动化设备》2024年第1期217-224,共8页Electric Power Automation Equipment

基　　金：国家电网有限公司华中分部科技项目(SGHZ0000DKJS2200231)。

摘　　要：针对国家电网“六统一”线路保护装置,提出了超、特高压交流线路反时限零序过流保护的整定原则。反时限零序过流保护在保证灵敏性方面并无困难,整定原则的核心问题是解决选择性和速动性的矛盾。根据该保护的原理和逻辑提出了转折电流的概念以及接地距离保护与反时限零序过流保护的配合原则;充分考虑配合时间定值和最小时间定值对保护动作特性的影响,综合超、特高压电网实际短路电流水平和接地距离保护的过渡电阻耐受能力,将反时限零序过流保护低电流区的选择性与接地距离保护高电流区的选择性进行结合,提升了对接地故障全域电流范围的选择性切除能力;提出了方向元件投退原则。通过对某省级电网进行算例分析,验证了整定原则的有效性,该整定原则已经在实际电网中进行了应用。The setting principle of inverse-time zero-sequence overcurrent protection for extra high voltage(EHV)and ultra high voltage(UHV)alternating current(AC)lines is put forward according to the“six uni⁃fied”line protection devices in State Grid Corporation of China.There is no difficulty in ensuring sensitivity for inverse-time zero-sequence overcurrent protection,and the key problem of setting principle is to solve the contradiction between selectivity and quickness.According to the action logic and characteristics of the inverse-time zero-sequence overcurrent protection,the concept of turning point current and the cooperation principle of the grounding distance protection and the inverse-time zero-sequence overcurrent protection are proposed.Fully considering the influence of matching time setting and minimum time setting on the protec⁃tion action characteristics,combining the actual short circuit current level of EHV and UHV AC power grids and the transition resistance tolerance of the grounding distance protection,the selectivity of inverse-time zero-sequence overcurrent protection in low current range is combined with the selectivity of grounding dis⁃tance protection in high current zone,which improves the ability of selective excision of the grounding fault in the whole current range.The principle of using directional element is put forward.The effectiveness of the proposed setting principle is verified by an example of a provincial power grid.The proposed setting principle has been applied in the actual power grid.

关 键 词：反时限零序过流保护 定时限零序过流保护 继电保护 高阻接地故障 超、特高压交流线路 选择性 速动性 整定原则 

分 类 号：TM77[电气工程—电力系统及自动化]