具有防过负荷误动的距离保护新方法  

A new method of distance protection preventing overload mal-operation

作　　者：李辉[1] 宋斌[1] 许捷[1] 陈兴松[1] 

机构地区：[1]国电南瑞科技股份有限公司,南京211106

出　　处：《电测与仪表》2015年第17期110-117,共8页Electrical Measurement & Instrumentation

基　　金：国家电网公司大电网重大专项资助项目课题(SGCC-MPLG003-2012)

摘　　要：针对事故潮流易造成线路传统距离保护III段误动的隐性故障问题,详细研究了过负荷和故障在Uφcosφφ和电压序分量相位等电气特征差异,提出了一种具有防过负荷误动的距离保护III段新方法。此方法包括两部分:基于Uφφcos(φφφ+90°-φline)<0.5UNN的全相过负荷与相间故障识别方法;基于电流不对程度、ARG(U·φ2/U·0)和ARG(U·φ1/U·0)的非全相过负荷与单相接地故障识别方法。介绍了具有防止过负荷误动的距离保护III段实施方案,并通过了RTDS仿真试验验证。In allusion to the problem of traditional zone Ⅲ distance relays can＇t identify the line overload and the line fault, this paper specifically analyses the electrical characteristics differences of the overload and the fault in Uφcosφφ and the change of phase, then a new method of distance protection zoneⅢ preventing overload real-operation is proposed. The method includes two parts ： one of them is a method to distinguish phase-to-phase faults from symmetrical overload, ：which is based On Uφφeos（φφφ ＋90° -φline） 〈0.5UNN ; the other of them is a method to distinguish singlephase earth fault from unsymmetrical overload, which is based on current asymmetry degree,ARG（Uφ2/U0 ） and ARG （Uφ1/U0） （φ = A ,B ,C）. The implementation scheme of distance protection zone III coping with overload real-opera- tion is proposed. The method is effective through RTDS simulation verification.

关 键 词：事故潮流转移 距离保护 隐性故障 过负荷 单相接地故障 

分 类 号：TM77[电气工程—电力系统及自动化]