【摘要】 为得到±800 kV宾金线浙江段沿线走廊正、负地闪多重回击特征,对2017年6月至9月监测到的3 032例完整地闪样本的特征参数进行了统计分析,主要包括回击次数、地闪持续时间、回击间隔时间、回击强度四个方面。多重回击参数呈明显的随回击序号系统性变化特征,且正、负地闪特性差异较为明显。统计结果表明:正、负地闪样本数量分别占27.57%和72.43%;负地闪样本中单回击占52.60%,最大回击次数达到13次,平均回击次数为2.47次;正地闪样本中单回击占比更大,达到77.04%,而回击次数相对较少,其最大回击次数为5次,平均回击次数仅为1.26次。正、负地闪多重回击持续时间随回击次数增加呈递增趋势,且负地闪持续时间的增长速度更快,其整体的算术平均分别为250.20 ms和343.02 ms。负地闪回击间隔时间随回击次序变化不明显,而正地闪回击间隔时间随回击次序呈递减趋势。总体上正、负地闪后续回击强度比值均随后续回击次序增加呈递减趋势;负地闪首次回击电流强度随回击次数增加呈递增趋势,而正地闪变化趋势不明显。更多还原

【Abstract】 In order to obtain the multiple return-stroke characteristics of positive and negative cloud-to-ground lightening in the corridor of the ±800 kV Binjin line in Zhejiang province, the statistical parameters of the 3 032 cloud-to-ground lightening samples monitored from June to September 2017 are statistically analyzed, including return-stroke times, cloud-to-ground lightening duration,return-stroke time interval, and return-stroke intensity. The multiple return-stroke parameters show obvious systematic variations with the return-stroke number, and the difference between positive and negative return-stroke characteristics is obvious. The statistical results show that the number of positive and negative lightening samples accounted for 27.57% and 72.43%, respectively.Single return-stroke account for 52.60% of negative lightening samples. The maximum number of return-stroke reaches 13, and the average number of return-stroke is 2.47. Single return-stroke account for 77.04% of positive lightening samples, and the number of return-stroke is relatively small. The maximum number of return-stroke is 5 and the average number is only 1.26. The durations of multiple return-stroke for positive and negative lightening are both positively correlated with the number of return-stroke and the overall arithmetic mean values are 250.20 ms and 343.02 ms, respectively. The negative return-stroke time interval does not vary significantly with the return-stroke order, while the positive one decreases with the return-stroke order. Overall, subsequent returnstroke intensity ratios of positive and negative lightening decrease with the subsequent return-stroke order. The first return-stroke current intensity of negative lightening increases with the number of return-stroke, while the trend of positive lightening is not obvious.更多还原