谐振接地系统单相接地故障频谱特征分析  

Frequency Spectrum Characteristic Analysis of Single-phase Grounding Fault in Resonant Grounded Systems

作　　者：张海申[1,2] 何正友[1] 张钧[1] 

机构地区：[1]西南交通大学电气工程学院,四川省成都市610031 [2]中铁第四勘察设计院集团有限公司,湖北省武汉市430063

出　　处：《电力系统自动化》2012年第6期79-84,共6页Automation of Electric Power Systems

基　　金：国家自然科学基金资助项目(50877068)~~

摘　　要：基于谐振接地系统单相接地故障暂态等值电路,从理论上详细分析了故障电阻变化时系统暂态特性的变化情况,得出在故障电阻较小时系统处于欠阻尼状态,随着故障电阻的增大,系统进入过阻尼状态,最后又过渡到另一种等值电路下的欠阻尼状态。建立了含电缆线路的谐振接地系统模型,仿真分析了电缆线路的引入,以及故障初相角、故障距离、故障电阻变化时,暂态零序电流及其频谱特征的变化规律。仿真结果表明:电缆线路的引入将使暂态电流频谱主成分向低频段移动;故障电阻的大小对含电缆线路的谐振接地系统单相接地故障暂态电流频谱特征影响很大。Based on the equivalent circuit of a resonant grounded system,the changes of the transient characteristics are analyzed theoretically when the fault resistance changes.The study indicates that the circuit is under-damped firstly,then it enters the damping state,and finally makes the transition to under-damped state.A resonant circuit model with cables is established,and the changing law of the zero-sequence transient current spectrum is analyzed when the cables are added to the distribution network and when the fault angle,fault resistance and fault distance are changed.Simulation results show that the adding of cables makes the spectrum of zero-sequence transient current move to a lower-band.Fault resistance has great influence on the spectrum of zero-sequence transient current.

关 键 词：谐振接地系统 暂态分量 频谱分析 特征频带 故障选线 配电网 

分 类 号：TM862[电气工程—高电压与绝缘技术]