小波包在配电网单相接地故障选线中的应用  

WAVELETS PACKET BASED DETECTION OF PHASE-TO-GROUND FAULT IN DISTRIBUTION AUTOMATION SYSTEM

作　　者：毛鹏[1] 孙雅明[1] 张兆宁[2] 杜红卫[1] 

机构地区：[1]天津大学电气自动化与能源工程学院,天津300072 [2]中国民航学院基础科学部,天津300300

出　　处：《电网技术》2000年第6期9-13,17,共6页Power System Technology

摘　　要：应用在时频空间皆具有良好聚焦特性的小波包 ,以适当频率带宽 ,对故障后暂态电气量进行分解。对于中性点接地方式不同的配电网 ,按照能量的观点 ,选择不同的频带来实现故障选线。基于选出的故障选线时频窗 ,提出了一种新型的选线判据 :以波形识别作主判据 ,以模值比较作副判据 ,经逻辑排序 ,最终给出故障选线序列。理论及大量的 EMTP仿真表明 :该选线方法可以准确、可靠地实现单相故障接地选线 ,适合于接地方式不同的各种配电网 ,而且现场安装简单、无需定值调节。Wavelet packets with the advantage of time frequency zoom is used in this paper to decompose the post fault transient electrical quantities by the proper frequency span. In view of energy, the different frequency band is chosen corresponding to the distribution system with the different neutral grounding mode. Based on the chosen time frequency window, a novel method is proposed in this paper, which synthetically uses the waveform recognition as the main criteria and the maximal module as the secondary criteria to perform the detection of the fault line. Theoretical analysis and lots of simulation using EMTP show that the proposed method can reliably and exactly choose the faulty line in single phase to ground fault and it is suited for various distribution systems with different neutral grounding modes. Moreover, this method can be easily used in site without adjusting protective settings.

关 键 词：配电网 小波包 故障选线 波形识别 单相接地 

分 类 号：TM727[电气工程—电力系统及自动化]