CAJ | 학술논문

直流气体绝缘金属封闭输电线路(gas insulated transmission line，GIL)在一些特殊环境下可替代部分架空输电线路或电缆提高输电走廊选择的灵活性。影响直流 GIL中绝缘子水平的关键因素有氧化铝填料比例、自由导电微粒等。该文对SF6气体中，负极性直流电压下不同氧化铝含量(250~400 phr)的环氧绝缘子在准均匀场和极不均匀场下的沿面绝缘特性和烧蚀特性进行了研究。结果表明，准均匀场情况下，填料含量250 phr的绝缘子在短时闪络特性和长时耐压特性方面都具有最好的沿面电气强度，同时在极不均匀场中也具有最好的沿面电气性能。而填料含量为350 phr的绝缘子则具有最差的直流耐压特性以及耐烧蚀特性。通过对闪络微观图像的分析，可知闪络过程发生在绝缘子的浅表面。同时，通过分析电树枝发展图像的分形维数，发现了填料含量对环氧绝缘子闪络烧蚀特性以及直流电压下的绝缘子电树枝发展特性的影响。
직류기체절연금속봉폐수전선로(gas insulated transmission line，GIL)재일사특수배경하가체대부분가공수전선로혹전람제고수전주랑선택적령활성。영향직류 GIL중절연자수평적관건인소유양화려전료비례、자유도전미립등。해문대SF6기체중，부겁성직류전압하불동양화려함량(250~400 phr)적배양절연자재준균균장화겁불균균장하적연면절연특성화소식특성진행료연구。결과표명，준균균장정황하，전료함량250 phr적절연자재단시섬락특성화장시내압특성방면도구유최호적연면전기강도，동시재겁불균균장중야구유최호적연면전기성능。이전료함량위350 phr적절연자칙구유최차적직류내압특성이급내소식특성。통과대섬락미관도상적분석，가지섬락과정발생재절연자적천표면。동시，통과분석전수지발전도상적분형유수，발현료전료함량대배양절연자섬락소식특성이급직류전압하적절연자전수지발전특성적영향。
DC gas insulated transmission line (GIL) can be utilized to substitute part of the overhead lines or cables in special environments to improve the flexibility of the selection of the transmission corridor. Key factors that greatly threaten the insulation level of DC GIL include free conducting particles and contents of alumina filler. Influence of the content of alumina filler on the characteristics of flashover and erosion of the alumina filled cast epoxy resin insulator in quasi-uniform field and highly non-uniform field in SF6 gas under negative DC voltage was investigated. Results show that among alumina filled epoxy resin insulators with filler contents from 250phr to 400phr, insulator with filler content of 250phr has most excellent surface dielectric strength than those of other insulators in both short-term flashover and long-term withstand voltage tests, as well as the best erosion property in both the quasi-uniform field and highly non-uniform field. While the insulator with filler content of 350phr has the worst performance. The flashover takes place in the shallow surface of the insulator according to its microscopic image of the flashover trace. Meanwhile, influence of the filler content on the erosion characteristics of the flashover and the tree properties under DC voltage were studied by analyzing the fractal dimension of tree trace of the flashover.