应用于直流GIL中环境友好型气体的绝缘性能研究  

Insulation Performance of Environmentally Friendly Gas Applied to HVDC-GIL

作　　者：王璁[1] 屠幼萍[1] 罗颜[1] 秦司晨 周福文 袁之康 WANG Cong TU Youping LUO Yan QIN Sichen ZHOU Fuwen YUAN Zhikang(Key Laboratory of High Voltage ＆ EMC, North China Electric Power University, Changping District, Beijing 102206, China)

机构地区：[1]高电压与电磁兼容北京市重点实验室(华北电力大学),北京市昌平区102206

出　　处：《中国电机工程学报》2016年第24期6711-6717,共7页Proceedings of the CSEE

基　　金：国家重点基础研究发展计划项目(973项目)(2014CB 239502)~~

摘　　要：直流气体绝缘金属封闭输电线路（gas insulated metal-enclosed transmission line,GIL）可提高特高压直流输电线路走廊选择的灵活性,研究其中SF_6气体的替代气体具有十分重要的意义。该文在负极性直流电压和负极性雷电冲击电压下,通过实验研究了0.4-0.7MPa气压范围内的SF_6、SF_6/N_2和CF_3I/N_2气体的击穿特性以及圆柱形绝缘子在相应气体环境中的闪络特性。结果表明：随着气压升高,SF_6、SF_6/N_2和CF_3I/N_2气体的击穿场强基本上呈现线性升高趋势,但同气压下SF_6的击穿场强最高,SF_6/N_2次之,CF_3I/N_2最低;CF_3I/N_2混合气体中绝缘子闪络电压远低于在SF_6和SF_6/N_2环境中。研究表明,0.7MPa气压、混合比为2：8的SF_6/N_2气体绝缘性能与0.5MPa时SF_6气体绝缘性能相当,且全球变暖潜能值（global warming potential,GWP）可降低约80%,可应用于直流GIL;而CF_3I/N_2混合气体由于其绝缘性能远低于SF_6和SF_6/N_2气体,不适用于高压直流气体绝缘金属封闭设备。Gas insulated metal-enclosed transmission line （GIL） can improve the flexibility on the choice of the UHVDC transmission line corridors. Therefore, theresearch of SF6gas replacement is of great significance. In this paper, under negative DC voltage and negative lightning impulse voltage, the experiment research of SF6, SF6/N2 and CF3I/N2 gases breakdown characteristic were applied within the scope of 0.4-4）.7MPa gas pressure. Under the samecondition of the gas, the corresponding cylindrical insulator flashover characteristics had been studied. The results show that with gas pressure increasing, SF6, SF6/N2 and CF6/N2 gas breakdown voltage presented the nearly linear growth trend, and in the same gas pressure, the breakdown field strength of SF6 is maximal, SF6/N2 is second, CF3I/N2is minimal. The insulator flashover voltage in CF3UNzgas mixture is far lower than it in the SF6/N2 and SF6gas. The results indicate that with 0.7MPa gas pressure, and mixture ratio of 2：8, SF6/N2 gas insulation performance and SF6 gas insulation performance with 0.5MPa gas pressure is almost equal, and GWP （global warming potential）can be reduced about 80%.As a consequence,the SF6/N2 gaswhich the pressure is 0.7 MPaand the mixture ratio is 2：8can be applied to HVDC-GIL. And compared with SF6/N2 and SF6 gas, CF3UN2 gas mixture is not suitable for high pressure gas insulated metal-enclosed equipmentbecause of the low gas insulation performance.

关 键 词：特高压直流 气体绝缘金属封闭输电线路 三氟碘甲烷 六氟化硫 替代气体 

分 类 号：TM855[电气工程—高电压与绝缘技术]