基于电压相量平面的单相高阻接地保护方案  

Vector diagram of voltage based single-phase high-resistance grounding fault protection scheme

作　　者：赵志仁 马伟 丁冬 王昀昀 刘友元 林森 景琦 ZHAO Zhiren;MA Wei;DING Dong;WANG Yunyun;LIU Youyuan;LIN Sen;JING Qi(Hangzhou City Construction Investment Group Limited,Hangzhou 310009,China;State Grid Hangzhou Power Supply Company,Hangzhou 310009,China;North China Electric Power University,Beijing 102206,China;State Grid Huaihua Power Supply Company,Huaihua 418000,China;State Grid Xi’an Power Supply Company,Xi’an 712000,China)

机构地区：[1]杭州市城市建设投资集团有限公司,浙江杭州310009 [2]国网浙江省电力有限公司杭州供电公司,浙江杭州310009 [3]华北电力大学,北京102206 [4]国网湖南省电力有限公司怀化供电公司,湖南怀化418000 [5]国网陕西省电力有限公司西安供电公司,陕西西安712000

出　　处：《电力系统保护与控制》2018年第22期131-136,共6页Power System Protection and Control

基　　金：国家电网公司科技项目资助(521104170012)~~

摘　　要：针对经过渡电阻发生单相接地故障时电流差动保护灵敏性降低的问题,提出了一种基于电压相量平面的单相高阻接地保护方案。首先,利用保护安装处的序电流与故障点电流相位近似相等的特点,计算线路两端电流的夹角。然后,通过对线路两端电流的夹角实测值与计算值求取差值,得到单相接地保护相角差。最后,根据单相接地保护相角差在区内故障与区外故障的差异,构造了单相高阻接地故障的动作判据。基于PSCAD/EMTDC的仿真结果表明,该方案不受故障相别、过渡电阻、故障位置、运行工况等因素影响,能够准确地反映保护区内与区外故障,且具有很高的灵敏性和可靠性,可作为电流差动保护的有效补充。In view of the problem that the sensitivity of current differential protection decreases when a single-phase grounding fault occurs via transition resistance,a single-phase high-resistance grounding backup protection scheme based on voltage phasor plane is proposed.Firstly,by using the characteristic that the sequence current phase of protection installation point is approximately equal to the one of fault point,the angle between the currents of two ends of the line is calculated.Then,the phase angle difference of single-phase ground protection is obtained by calculating the difference between the measured value and calculated value of the angle between the currents of two ends of the line.Finally,based on the difference between internal and external fault in phase angle difference of single-phase grounding protection,the operating criterion of single-phase high-resistance grounding fault is presented.Simulation results based on PSCAD/EMTDC show that the scheme is immune to the fault phase,transition resistance,fault location,operating condition and other factors.It can accurately reflect internal-fault or external-fault with high sensitivity and reliability,which can be used as an effective supplement of current differential protection.

关 键 词：输电线路 电压相量平面 单相接地 后备保护 过渡电阻 

分 类 号：TM862[电气工程—高电压与绝缘技术]