This paper introduces an HVDC SF6/N2 gas-insulated transmission line (GIL) prototype that operates under 100-kV DC application. In the first part, the development history of GIL products over the past 50 years is reviewed. After that, the design concept of the ±100-kV HVDC SF6/N2 GIL is introduced. A GIL prototype was prepared and the DC withstanding voltage test and DC superimposed lightning impulse voltage test were performed. The results show that this GIL prototype passed all the required tests, including hydrostatic test, gas tightness test, thermal cycling test, DC withstanding test, and DC superimposed impulse test, etc. The successful preparation of this product promoted a major step in researches of the DC GIL and the prototype laid a solid foundation for the development of subsequent industrial products.

中文翻译：

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$\pm$100-kV HVDC SF6/N2 气体绝缘输电线路

本文介绍了一种在 100 kV 直流应用下运行的 HVDC SF6/N2 气体绝缘输电线路 (GIL) 原型。第一部分回顾了GIL产品50年来的发展历程。然后介绍了±100-kV HVDC SF6/N2 GIL的设计理念。制备了GIL样机，进行了直流耐压试验和直流叠加雷电冲击电压试验。结果表明，该GIL样机通过了水压试验、气密性试验、热循环试验、直流耐压试验、直流叠加冲击试验等所有要求的试验。该产品的成功制备推动了其研究的重要一步。 DC GIL和样机为后续工业产品的开发奠定了坚实的基础。