【作者】 车伟；

【导师】 李训铭；

【作者基本信息】 河海大学 ， 控制理论与控制工程， 2003， 硕士

【摘要】 小电流接地系统单相接地故障定位一直是人们关注和研究的焦点，随着配电网自动化水平的提高，对其研究的迫切性已日益紧迫。 本论文主要研究了小波分析在小电流接地系统单相接地故障定位中的应用，利用小波变换这一新兴的信号分析工具，提取故障时的暂态电量信息，构造出了基于小波变换模极大值奇异性检测原理的新型选线判据。新判据以更充分更准确的提取信号奇异性信息为出发点，利用小波对暂态突变信号或微弱变化信号处理上的优势，弥补了以往传统的基于稳态信号分析原理不足，增强了抗干扰能力，具有更高的可靠性和准确性。 对小电流接地系统电弧故障的选线仿真是本文的重点，也是一个创新点，本文从研究的角度，在深入分析电弧接地时故障电压、电流的特点和变化情况的基础上，进行了大量的选线仿真，仿真表明电弧故障时，小波分析方法也能准确地选出故障线路，这对研制高性能的接地保护装置将起到重要的指导作用。 本文将行波故障测距原理在小电流接地系统中进行了初步尝试，利用小波变换对奇异性检测的强大功能，检测行波波头的到达时刻，实现故障测距，为小电流接地系统单相故障测距装置的研制开辟了新的途径，为配电网自动化水平的提高迈出了重要的一步。更多还原

【Abstract】 The single phase grounding fault location is the focus which researchers pay attention to and study in the small current grounding power systems. With the improvement of automatic level in distribution systems, the study about it is urgent daily.In this paper, the important point is the study about the application of wavelet analysis in single phase grounding fault location of small current grounding power systems, wavelet transform is used as a novel tool of signal analysis to obtain useful fault transient components, a new criterion of fault line selection is constructed based on the time and frequency localization character of wavelet transform. The new criterion obtain the singular signal fully and exactly as the jumping-off place, take advantage of wavelet disposing the transient singular or faint signal, scarcity of the analyzing principle based on steady signal is fetched up and enhance the anti-disturb capability, so that it has higher reliability and accuracy.Arc-grounding fault line selection is the paper’s key point and innovative point about small current grounding power systems. A lot of simulations are made based on the change rule and the character of fault voltage, fault current. The simulation study declare that the use of the method of wavelet analysis can select the fault line when the arc-grounding fault take place, it will play a important directive role in the research of the protection equipment.The fault location principle that utilizes traveling wave is used in the small current grounding power systems firstly in my paper. Using the powerful function of wavelet in the face of singular detection, the time that the wave crest arrives are detected and the fault location is realized. This paper provides a new approach for the research of equipment of the single phase grounding fault location and makes a significant step for the improvement of automation level in the distribution systems.更多还原