摘要
对闪电电场变化波形进行时域特征分析,研究闪电放电类型识别方法,是闪电探测系统研制工作的重要组成部分。利用闪电快电场变化资料,研究分析闪电波形的时域特征,分别统计负地闪回击和双极性窄脉冲波形的上升时间、下降时间、脉冲宽度等多个特征参数,得出负地闪回击波形上升时间平均值为2.9μs、下降时间平均值为89μs、脉冲宽度平均值为15.4μs,而双极性窄脉冲波形的上升时间平均值为1.7μs、下降时间平均值为2.1μs、脉冲宽度平均值为2.4μs。通过对闪电波形参数的统计分析,给出了不同放电过程的识别判据,实现了对地闪回击、双极性窄脉冲的自动识别,并利用实测数据进行了验证。结果表明,制定的波形识别判据对负地闪回击的识别效率可达到90%,对正地闪回击与双极性窄脉冲事件也有较高的识别率。
The time-domain analysis on waveform change of lightning electric field and the identi- fication of discharge types are one of the most important works in the study of lightning detection system. The rise-time, fall-time, pulse-width and a series of time-domain features of return strokes and narrow bipolar events were given through analyzing the fast electric filed change data our system acquired. The rise-time of the negative return-stroke fields had an average of 2.9/,s, its fall-time and pulse-width were 89μs, 15.4μs on average. The average rise-time value of the narrow bipolar events was 1.7μs. The mean of the fall-time value and pulse-width value of narrow bipolar events were 2.1μs and 2.4μs, respectively. Some of the results were consistent with other researcher＇ s, but some differences existed which is caused by the different equipment used. Nev- ertheless all the waveform features we got was still valuable for the identification. Based on these characteristics, a set of software which could distinguish return strokes and narrow bipolar events automatically from all of the lightning radiations events was designed. The classification results were tested by manual selection of data, and it proved a 90 % correctness of identifying negative return strokes and a desired accuracy of identifying positive return strokes and narrow bipolar events. As a preliminary research of the waveform classification of lightning discharge events, this method already has a practical value. It can be used to distinguish cloud-to-ground lightning, cloud-to-cloud lightning and narrow bipolar events in the new lightning detection system.
出处
《气象》
CSCD
北大核心
2009年第3期49-59,共11页
Meteorological Monthly
关键词
波形识别
回击
双极性窄脉冲事件
闪电探测
waveform identification return strokes narrow bipolar events lightning detection
