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,提出了一种选线依据:根据能量最大的原则选择特征频带来获取暂态电容电流的主要特征,然后比较各条线路特征频带的模最大值点和零序电压首半波的极性以确定故障线路。
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 method is proposed in this paper. Based on the principle of maximum energy, it selects the special frequency band that has the major characteristics of transient capacitance current. Comparing the polarity of the special frequency band of each line with the polarity of the zero sequence voltage' s first half wave, which can detect the fault line.
出处
《水利电力机械》
2007年第1期26-28,共3页
Water Conservancy & Electric Power Machinery
关键词
配电网
小波包
故障选线
distribution electric network system
wavelet packets
fault line selection