. . 山东农业大学毕 业 论 文 小电流接地系统故障自动选线仿真及研究 院 部 机械与电子工程学院 专业班级 电气工程及其自动化5班 届 次 2015届 学生姓名 学 号 指导教师 二一五年六月五日装订线. . . . . . . 目 录摘要IAbstractII1 引言11.1 课题研究的背景及其意义11.2 小电流接地系统单相接地故障选线研究现状11.2.1 国外研究现状11.2.2 国内研究现状12 小电流接地系统单相接地故障特征分析22.1 电力系统中性点接地方式概述22.2 小电流接地系统单相接地故障稳态特征分析22.2.1 中性点直接接地系统22.2.2 中性点不接地系统22.2.3 中性点经消弧线圈接地系统52.3 小电流接地系统单相接地故障暂态特征分析72.3.1 暂态电容电流82.3.2 暂态电感电流92.3.3 暂态接地电流93 小电流接地系统选线方法综述103.1 利用电网稳态电气量提供的故障信息构成的自动选线法103.1.1 零序电流比幅法103.1.2 零序电流群体比幅比相法103.1.3 基于五次谐波分量的选线方法103.1.4 零序电流有功分量法113.1.5 零序电流无功功率方向法113.1.6 最大或()法113.1.7 能量法113.2 利用电网暂态电气量提供的故障信息构成的自动选线法123.2.1 基于小波分析的选线方法123.2.2 首半波法123.3 其他方法123.3.1 拉线法123.3.2 注入信号法124 小电流接地系统自动选线仿真124.1 基于零序电流比幅法原理选线的仿真124.1.1 多回路的架空线路仿真124.1.2 多回路电缆线路仿真154.2 基于零序功率方向法原理选线的仿真184.2.1 架空线路的仿真184.2.2 电缆线路的仿真194.3 基于五次谐波电流法原理选线的仿真204.3.1 接地电阻为100时204.3.2 接地电阻为400时215 结论23参考文献24致谢25附录26ContentsAbstractII1 Introduction11.1 Background and significance of the research11.2 Research status of single phase grounding fault line selection for small current grounding system11.2.1 Foreign research status quo11.2.2 Domestic research status quo12 Analysis of single phase grounding fault in small current grounding system22.1 Overview of neutral point grounding in power system22.2 Analysis of the steady state characteristics of single-phase grounding fault in small current grounding system22.2.1 Neutral point direct earthing system22.2.2 Neutral point is not grounded system22.2.3 Earthing system of the neutral point via the arc suppression coil52.3 Transient characteristic analysis of single phase to earth fault in small current grounding system72.3.1 Transient capacitance current82.3.2 Transient inductance current92.3.3 Transient grounding current93 Overview of the selection of small current grounding system103.1 Automatic wire selection method based on the fault information provided by power grid steady electrical quantity103.1.1 Zero sequence current ratio method103.1.2 Zero sequence current group ratio phase method103.1.3 Line selection based on five harmonic components103.1.4 Active component method for zero sequence current113.1.5 Zero sequence current reactive power direction method113.1.6 The maximumor()method113.1.7 Energy method113.2 Automatic wire selection method based on the fault information provided by power grid transient electric quantity123.2.1 Line selection based on wavelet analysis123.2.2 First half wave method123.3 Other methods123.3.1 Pull method123.3.2Injection signal method124 Automatic wire selection simulation for small current grounding system124.1 Simulation of line selection based on zero sequence current ratio method 124.1.1 Simulation of multi circuit overhead line124.1.2 Simulation of multi circuit cable line154.2 Simulation of the line selection based on zero sequence power direction method184.2.1 Simulation of aerial line184.2.2 Simulation of cable line194.3 Simulation of line selection based on five harmonic current method204.3.1 Ground resistance of 100204.3.2 Ground resistance of 100215 Conclusion23Reference24Acknowledgement25Appendix26iv小电流接地故障系统自动选线仿真及研究王希涛 （山东农业大学 机械与电子工程学院 泰安 271018）摘要：本文首先论述了课题的背景和意义，概括国内和国外的研究状况，分析了小电流单相接地故障的特征，包括暂态和稳态故障信息，并对基于此故障信息的选线方法，对其进行了包括原理在内的简要介绍和比较，随后选取了几种选线方法，运用Matlab中的Simulink软件包进行了仿真，根据仿真结果和分析，分析当前自动选线法存在的问题及今后的展望。关键词：小电流接地系统 单相接地故障 选线 注入法 MatlabSimulation and Research of Automatic Wire Selection for Small Current Fault SystemXitao Wang(Mechanical & Electrical Engineering College of Shandong Agricultural University, Taian, Shandong 271018)Abstract First of all, this paper discusses the background and significance of the topic, throughout the domestic and foreign research situation, analyzes the small current single phase grounding fault features, including the steady state and transient fault information, and based on the methods of fault line selection in the fault information and the the principle, brief introduction to and comparison, then select the several methods of fault line selection and use a kind of software package for the simulation in MATLAB, according to the simulation results and analysis, analysis of problems and future prospect of the automatic line selection method.Keywords: the small current grounding system; single phase ground fault; line selection; injection method; Matlab26