摘要
首先,对小电流接地系统的单相接地故障进行仿真,分析故障后暂态零序电流的特征,即在暂态初始阶段的暂态故障电流主要由暂态电容电流所决定,因此故障线路的暂态零序电流幅值最大。若忽略暂态电感电流,则故障线路的暂态零序电流幅值等于所有健全线路的幅值之和,且方向与非故障线路相反。因此,在求得各线路的暂态零序电流变化率后,通过比较它们的大小和极性就能准确定位出故障线路。最后,采用Matlab搭建仿真模型,对不同的电压初始相角、过渡电阻、故障位置以及中性点的不同接地方式进行仿真实验。仿真结果证明该方法能够准确、迅速地定位出故障线路,具有较强的可靠性、实用性。
First of all, the simulation of one-phase grounding fault is made for the small current grounding system. And then analysis the characteristics of the transient zero sequence current. In the initial stages, the transient fault current mainly decided by the transient capacitance current, so the fault line transient zero sequence current＇s amplitude is the largest. If you ignore the transient inductance current, then the fault line transient zero sequence current＇s amplitude is equal to the sum of all sound lines＇ amplitude. The direction of the fault line is opposite to all sound lines＇. Therefore, after we obtain the change rate of transient zero sequence current for each line, we can locate the fault line accuracy by comparing the size and polarity of them. Finally, the simulation model based on Matlab is set up for different voltage initial phase angle, transition resistance, fault location and different neutral grounding manners. The simulation results prove that the method can locate the fault line accurately and quickly with strong reliability and practicability.
出处
《电气技术》
2013年第2期27-30,35,共5页
Electrical Engineering
关键词
小电流接地系统
故障选线
暂态零序电流
变化率
small current grounding system
fault line selection
transient zero sequence current
change rate
