摘要
通过传输线模型的理论分析,利用理论推导与实验相结合的方法,采用架空导线耦合模拟雷电进行实验。结果表明,当雷电回击通道中雷电流在5~29 kA范围时,架空导线耦合雷电电磁波形成的过电压幅值随雷电流的增大呈线性增加;耦合的能量随雷电流的增大呈幂函数关系增加;并且随导线长度的增加,耦合到的过电压和能量均减小;随导线截面积的增大,耦合到的过电压和能量均增大。
Given the increasing importance of the power system to society,as well as the increasing sophistication of electronic equipment,studying lightning-induced voltage changes on overhead lines is of great practical significance.Due to the low probability of overhead lines being struck directly by lightning,accounting for about 10% of all lightning strikes,lightning is the main factor causing power transmission line faults.A number of analyses were carried out in this study,including the establishment of the lightning return stroke channel,the development of an Earth and overhead wires integrated model,the simulation of overhead line coupling of the lightning current tests,and comparative analysis and simulation.The simulated lightning current impulse generator,and the metal rods at both ends of the metal rod,with a height of 1.2 m and diameter of 20 mm,and the 8/20 μs electromagnetic wave transmitted in a simulated lightning channel,are applied in the simulation of the lightning.The electric dipole is applied at both ends of the metal bar from a lightning impulse of 5 kA to 29 kA and current step size of 2 kA.When the over-voltage amplitude of the current in the lightning return stroke channel is from 5kA to 29 kA,the amplitude of over-voltage in the process of the overhead conductors coupled with lightning electromagnetic increases linearly with the lightning current;coupling energy shows a good power function with the lightning current.Overhead conductors lightning electromagnetic coupling is indicated not only by the over-voltage amplitude and magnitude of the lightning current,but also by the overhead wire length and related cross-sectional area.The longer the overhead wire,the smaller the over-voltage and power energy.And the greater the cross-sectional area of the lightning electromagnetic coupling formed,the larger the over-voltage and energy.
出处
《大气科学学报》
CSCD
北大核心
2017年第1期127-131,共5页
Transactions of Atmospheric Sciences
基金
苏州市气象局立项课题(SZ201507)
关键词
架空导线
耦合
模型
雷电电磁波
传输线理论
overhead conductor
coupling
model
lightning electromagnetic waves
theory of transmission lines
