基于零序功率变化量的配电网单相高阻接地保护  

Protection Principle of Single-Phase High Resistance Fault for Distribution Network Based on Zero-Sequence Power Variation

作　　者：龙毅 欧阳金鑫[1] 熊小伏[1] 马格土 杨明波 Long Yi;Ouyang Jinxin;Xiong Xiaofu;Ma GetuYang;Mingbo(State Key Laboratory of Power Transmission Equipment&System Security and New Technology,Chongqing University,Chongqing 400030,China;Guizhou Power Grid Co.Ltd,Guiyang Power Supply Bureau,Guiyang 550004,China)

机构地区：[1]输配电装备及系统安全与新技术国家重点实验室(重庆大学),重庆400030 [2]贵州电网有限责任公司贵阳供电局,贵阳550004

出　　处：《电工技术学报》2019年第17期3687-3695,共9页Transactions of China Electrotechnical Society

基　　金：国家重点研发计划(2016YFB0900600);贵州电网有限责任公司科技项目(GZKJXM20170166)资助

摘　　要：针对中性点经小电阻接地系统面临单相高阻接地故障难以有效切除而存在较大安全隐患的问题,提出一种基于零序功率变化量的小电阻接地系统单相高阻接地保护方法。首先分析了中性点经小电阻接地配电网正常运行和单相高阻接地故障下的零序电流分布特征,在此基础上,构造了馈线零序功率作为配电网单相接地故障判别的特征量;然后利用非故障馈线零序功率变化量小而故障馈线零序功率变化量反映过渡电阻有功功率的特点,提出基于零序功率变化量的配电网单相接地保护原理及其整定方法。理论和仿真分析表明,该保护原理仅利用单端信息即可准确反映较高过渡电阻,受线路对地参数及电容电流的影响小,具有较高的可靠性和适应性。Since the single-phase high resistance fault is difficult to be effectively removed from the low-resistance grounding system,which has a large potential safety hazard.A single-phase high resistance fault protection method based on zero-sequence power variation is proposed in this paper.Firstly,the zero-sequence current distribution characteristic in the normal operation and single-phase high resistance fault are analyzed theoretically.On this basis,the zero-sequence power of the feeder is constructed as the characteristic of the single-phase fault identification of the distribution network.Then,utilizing the characteristic that the zero-sequence power variation of the non-fault feeder is small while the zero-sequence power variation of the fault feeder reflects the active power of transition resistance,the principle of single-phase fault protection based on zero-sequence power variation for the distribution network and its setting method are proposed.Theoretical and simulation analysis shows that the protection principle can accurately reflect the higher transition resistance with only single terminal information,and is less affected by the line-to-ground parameters and capacitance current,and has higher reliability and adaptability.

关 键 词：配电网 小电阻接地系统 单相高阻接地故障 零序功率变化量 

分 类 号：TM771[电气工程—电力系统及自动化]