摘要
2018—2019年夏季在广州从化开展了火箭引雷试验,雷击对象分为两种,分别是架空线路和地面。对比了两种引雷情况下各阶段雷电流的电流波形参数的差异,发现引雷至地面情况下初始阶段的最大电流、平均电流、转移电荷、作用积分分别是引雷至架空线路情况下的2.8、2.4、2.0、5.3倍。引雷至地面情况下回击的上升时间几何均值为0.25μs,小于引雷至线路情况下的0.60μs,而对于电流峰值等其他回击波形参数而言,差异不明显。M分量与初始连续电流脉冲类似,引雷至线路情况下的电流峰值、转移电荷、连续电流水平均小于引雷至地面情况下的。基于诺顿电流源等效电路模型分析两种引雷情况下雷电流不同阶段存在差异的原因,可能是雷电在不同电流阶段时其通道等效阻抗不一样所导致的。
Most of the current rocket-triggered lightning experiments are conducted with lightning strikes on the ground.Related studies have shown that the properties of the struck object affect the parameters of the lightning.The paths of the lightning flow are very different between direct lightning strikes on the ground and direct lightning strikes on overhead line.It is necessary to obtain the lightning parameters of a real overhead line direct strike and analyze the similarities and differences between them and the ground direct strike lightning parameters for power system lightning protection.Rocket-triggered lightning experiments were conducted at the Guangzhou Field Experiment Site for Lightning Research and Testing in Conghua,Guangzhou,during the summer of 2018 and 2019.Lightning strikes objects are divided into two kinds,one is overhead line and the other is ground.When lightning strikes on the ground,the lightning current is introduced by the inducing rod to the current measuring equipment installed in the ground launcher,and flows directly into the soil after measurement(grounding resistance is 6.7Ω).When the lightning strikes on overhead line,the lightning current is first introduced by the current measuring equipment installed in the top of the tower launcher,measured and then flows into the 10 kV overhead line via a wire,and finally the majority of the lightning current flows into the soil via the two nearest towers(the characteristic impedance of the overhead line is about 200Ω).The current parameters characteristics of the initial stage,return strokes and M-components in the case of lightning to ground and lightning to overhead line are analyzed to compare whether they differ and to analyze the reasons for the differences.The maximum current,average current,transfer charge,and action integral of the initial stage in the case of lightning to the ground are 2.8,2.4,2.0,and 5.3 times those of the lightning to the overhead line.There is no significant difference in the duration of the initial stage between two conditions.The geometric mean of the rise time of the return stroke when the lightning strikes the ground is 0.25μs,which is much smaller than 0.60μs when the lightning strikes the overhead line.For other waveform parameters of return strokes such as the current peak,the difference is not obvious.The M-components are similar to the initial continuing current pulses,and the current peak value,transfer charge,continuing current level in the case of lightning to the overhead line are all smaller than those of the lightning to the ground.The rise time,half-peak width,and duration of the M-components are also smaller than those of the lightning to the ground,with the former being about 0.56,0.59,and 0.40 times the latter.Analysis based on Norton current source equivalent circuit model.The reason for the difference in lightning current between the two lightning conditions is that the equivalent impedance of the lightning channel is different in each stage.
作者
蔡力
杜懿阳
胡强
彭向阳
陈绍东
Cai Li;Du Yiyang;Hu Qiang;Peng Xiangyang;Chen Shaodong(School of Electrical Engineering and Automation Wuhan University,Wuhan 430072,China;Guangdong Grid Electric Power Research Institute,Guangzhou 510000,China;Guangzhou Institute of Tropical and Marine Meteorology China Meteorological Administration,Guangzhou 510080,China)
出处
《电工技术学报》
EI
CSCD
北大核心
2024年第3期914-923,共10页
Transactions of China Electrotechnical Society
基金
国家自然科学基金(52177154)
中央高校基本科研业务费专项资金(2042023kf0183)资助项目。
关键词
火箭引雷
架空线路
雷电流
回击
Rocket triggered lightning
overhead line
lightning current
return stroke
