文档介绍：华北电力大学(保定)
硕士学位论文
变电站接地网参数计算与分析
姓名:陈建军
申请学位级别:硕士
专业:电气工程
指导教师:律方成
2011-03
华北电力大学硕士学位论文
摘要
接地网是变电站电气设备的公共参考地,是变电站人身安全和设备安全运行
的重要保证。在系统发生故障的情况下,变电站接地网将故障电流迅速泄入大地,
并将地电位降低到人体跨步电压和接触电压耐受值以下,且不会让高电位对二次
设备发生反击,以保证人身和设备安全。所以,接地网在变电站安全运行中起着
十分重要的作用,本文主要从以下几方面讨论。
1、给出了在分层导电媒质中的点电流源产生的恒定场的计算方法。在镜象
法的基础上引出复镜象法,并基于复镜象法推导出水平三层土壤中格林函数的计
算方法。
2、地网接地参数不等电位与地网等电位的数值计算结果明显存在一定差别。
在设计变电站大型地网时,必须对接地导体材料的选择、接地导体半径的选择、
接地阻抗、接触电压、跨步电压和短路电流多点注入地网等分别进行分析。
3、由于土壤电阻率自身的测量误差,使得接地阻抗的测量值与真实值之间
具有较大的测量误差。深入研究了测量接地阻抗时水平双层土壤和垂直双层土壤
中电流极和电压极的布置方法。分析了现有测试方法测量接地阻抗的误差。
4、运用接地网设计分析软件,对变电站接地网接地性能进行了系统的计算
分析,为变电站设计提供了必要的参数。

关键词:接地网;接地阻抗;变电站;接地阻抗测量

I
华北电力大学硕士学位论文
Abstract
To ensure safety of people and to protect various electric devices within
substation, the substation grounding grid is a reference ground of the various electric
devices. The failure current drains quickly to the ground through grouding grip
during a fault of an electric power system, the touch votage and step votage is
reduced under the tolerance , the grounding system is ponents
of a substation. In this paper, the following several e into question.
1. The method for calculating stationary current field which is engendered by
point current source in multiplayer media is introduced. plex image method is
dicussed on the basis of the image method, then an efficient menthod is derived for
calculating Green’s function of horizontal three-layer soil.
2. The method of calculation is obviously different between the Constant
Voltage Model and Ranging from potential model. Some grounding parameters must
be analyzed such as grounding resistance, touch votage and step votage,while the
station grounding grip is designed.
3. Measurement error of grounding impedance may be very large because the
measurement error of soil resistivity. The grounding impedance must be measured
after grounding system is constructed. The arrangement of current and voltage probes