【作者】 王凤；

【导师】 康怡；

【作者基本信息】 华北电力大学（河北） ， 信号与信息处理， 2008， 硕士

【摘要】 中性点非有效接地系统单相接地故障选线问题一直以来是电力系统继电保护工作的重要课题。但现场运行的结果表明,装置的选线效果并不是十分理想。以往选线装置大多采用的是单一的被动式故障选线方法,且其采集信号不是利用零序电流的暂态量就是利用其稳态量。本论文提出了一种可控的周期性主动式检测方法——脉冲信号注入法。应用Matlab/Simulink建立了模型,通过对不同条件下的各种接地故障情况的仿真研究,提出对NUS采用基于差值运算法提取脉冲响应信号,再通过波形识别来进行故障选线的方法;对NES采用基于小波变换提取脉冲响应信号,进而通过群体比幅法来达到故障选线目的的选线方案。经过理论分析和仿真验证,上述方法是切实可行的。更多还原

【Abstract】 Fault detection for the non-effective single-phase earth system is an important task for ensuring the continuity of power supply. But the spot records show that the effect is not perfect. Most of the fault detection device in the past is used in a single passive fault line detection method, and it collects signals by the means of transient volume of the zero-sequence current or steady volume. Pulse injection method is proposed in this paper. It is a controllable cycle pulse responds method and can detect the fault positively. A simulation model is built by using Matlab/Simulink. And simulations of various ground faults under different conditions are performed. It is presented in the paper that in the fault detection of NUS system impulse response signal is extracted based on the method of margin calculation, and the fault line selection method is carried out by the waveform recognition. In the fault detection of NES system the impulse response signal is extracted based on wavelet transform, then the fault is detected by colony amplitude comparison. After theoretical analysis and simulation, the results show that this approach is practicable.更多还原