摘要
我国"西电东送"工程中大量采用了直流输电方式,而西南地区高海拔、多山区的特点将对输电系统的绝缘配合提出更高的要求。为研究高海拔地区直流输电系统的雷电过电压特性,采用PSCAD/EMTDC仿真软件对溪洛渡工程中±500 kV昭通换流站直流侧的雷电过电压进行了计算和分析,模型考虑了海拔和山区地形的影响,根据换流站直流侧反击和绕击雷电侵入波过电压的计算结果,得出高海拔地区换流站直流侧的雷电过电压特性,为优化换流站雷电防护提供参考依据。另外,对绕击侵入波过电压,着重比较了绝缘子串临界不闪络对应的雷电流幅值与EGM模型计算的最大绕击雷电流幅值下设备的过电压,发现按照传统方式以最大绕击雷电幅值计算设备的最大过电压可能会丢失过电压水平最严重的情况。
The ＂West to East Power Transmission＂ project in China adopts a series of HVDC transmission lines, where transmission system in southwest China requires high quality of insulation coordination owing to the characteristics of high altitude and mountainous topography. To study on characteristics of lightning overvoltage of HVDC transmission system in high altitude area, model of the DC part of ~500 kV Zhaotong station in Xiluodu project is buih using PSCAD/EMTDC. Taking into account the effects of altitude and mountainous terrain, back flashover lightning overvoltage and shielding failure lightning overvoltage of the DC part of converter station are calculated, and the characteristics of lightning overvoltage of equipment are derived from the results and a valuable reference to guide lightning protection of converter stations is provided in this article. Moreover, for shielding failure lightning overvoltage, there are two methods to choose the lightning current amplitude： the current when the insulator string critical not flashover and the maximum current derived from EGM model, and the two methods are co to show that the second method may lose the most serious cases.
出处
《电瓷避雷器》
CAS
北大核心
2016年第6期140-145,共6页
Insulators and Surge Arresters
