基于计算电阻的发电机定子单相接地保护方案分析  

Protection Project Analysis on Generator Stator Single-phase Grounding Faults Based on Calculated Resistance Measurement

作　　者：孙翠英[1] 胡立章[2] 朱思旭[1] 古海峰[1] 

机构地区：[1]国网河北省电力公司电力科学研究院,石家庄050021 [2]国网河北省电力公司信息通信分公司,石家庄050021

出　　处：《河北电力技术》2015年第6期14-17,共4页Hebei Electric Power

摘　　要：分析发电机单相接地故障前后中性点侧及机端侧相电流变化情况,提出了一种基于计算电阻的发电机定子单相接地保护方案,通过计算各机组在单项接地故障前后的接地电阻,来判定故障点是否位于发电机定子绕组内部。进行EMTP仿真分析,结果表明该设计方案能可靠识别出多发电机并联运行时发生在某一发电机内部的接地故障,能准确判断出故障机组,其构成原理较简单、直观,有利于提升中小型水电站中发电机定子单相接地保护的性能。The phase current difference between generator neutral points and generator terminals is analyzed, a selective protection for generator stator grounding faults in MGS is proposed. On the base of measuring the calculated resistance, the stator grounding faults can be detected. EMTP simulation analysis shows that the protection project can be identified reliable generator of the internal fault, the fault judgment generator. Its principle of a simple, intuitive, will help to improve small and medium-sized hydropower stations in the single-phase ground generator stator protection performance.

关 键 词：发电机 接地保护 选择性 计算电阻 

分 类 号：TM310.73[电气工程—电机]