考虑绝缘闪络和杆塔的冲击电晕对输电线路中雷电波传播的影响研究

在中国设计变电站设备的闪电绝缘时,并未考虑由于冲击电晕效应使入侵波在沿传输线上传播时发生的衰减和畸变,因此对于电气的绝缘要求过于严格,对于交流传输线产生的电晕的研究十分的有必要。在电晕模型中加入了更加符合实际情况的传输线的杆塔模型和绝缘子闪络模型;这一模型更好地模拟出了实际的电晕对传输线的影响过程。利用上述原理建立了基于ATP-EMTP仿真软件应用实际的传输线上的电晕模型。通过仿真计算发现,由于电晕的存在,雷电波波头时间被拉长而且幅值减小,即波形发生了衰减和畸变。雷击点距测量点的距离越远、波头时间越长、畸变现象越严重。考虑了绝缘子闪络和有杆塔时模拟得到的输电线路有电晕情况下的雷电压波形,结果显示幅值小了79.8%;对于指导输电线路终端设备安装电涌保护器具有十分重要的现实意义。

On the Propagation of Lightning Wave Considering Impulse Corona with insulation flashover model and tower model

In designing lightning insulation margin of substation equipment in China, the attenuation and distortion of intruding wave caused by corona in the transmission lines is neglected, thus making too strict insulation requirements on the electrical equipment, it necessary to study the corona effect of AC transmission lines. In this papper, based on the mathematic model of impulse corona add tower models of transmission line and insulator flashover model, which is more practical than before. This model better simulate actual Corona effect on transmission line. Using the above mentioned principle based on EMTP simulation software is built on the actual application of transmission-line model of corona. According to the simulation, the results are coincidence with the experimental results. The front of lightning wave become longer and the crest is decreased. And this phenomenon is graver when the measured point is far from the stroke point. Considered insulator flashover model and transmission lines tower model when there is lightning Corona case pressure waveform, the peak values of the voltage were reduced by 79.8%. This research has significance on the use of the surge protective device.