Study of Fundamental Characteristic in Electrical Insulation Using Paper-Ice Composite Insulating System for High Temperature Superconducting Power Cable

高温超导电力电缆的研究工作随着电力需求的增长而不断推进。超导电力电缆绝缘材料的选择对超导电力电缆的实际应用具有重要意义。作为保温体系之一，研究了由绝缘纸-LN_2制成的复合保温体系。然而，在常规的纸-液氮（LN_2）绝缘系统中，纸内存在微小气泡，容易发生局部放电。为了解决这一问题，我们发明了纸-冰复合绝缘系统，以替代纸-LN_2在低温电绝缘系统中的应用。发现多纸层-冰复合绝缘系统的电击穿强度高于多纸层-LN_2复合绝缘系统。另外，还报道了纸-冰复合绝缘子与杂质颗粒导电时，击穿强度的下降率 ...更多信息 与纸-LN_2复合保温系统相比，复合保温系统体积小。本文研究了导电杂质对纸-冰复合绝缘体系的电击穿特性等的影响，结果表明，含金属杂质的OF-纸B的击穿强度高于纸密度较低的OF-纸A，且与不含金属杂质的OF-纸A的击穿强度相同。在寿命试验中发现，含金属夹杂物的纸-冰复合保温系统的寿命低于不含金属夹杂物的纸-冰复合保温系统，而纸-LN_2复合保温系统的寿命几乎没有降低。研究还表明，即使在纸-冰复合绝缘系统中存在金属夹杂物，该系统在3倍局部放电电场下的寿命也优于具有或不具有金属夹杂物的纸-液氮复合绝缘系统。少

The research work for high temperature superconducting power cable has advanced to deal with increment of electric power. It is important that what is elected as insulating materials for the practical application of superconducting power cable. A composite insulating system made of insulating paper-LN_2 has been studied as one of the insulating system. However, in paper-liquid nitrogen (LN_2) insulating system using conventional techniques, micro bubbles remain inside the paper and the partial discharge could occur easily. To overcome this problem, we invented the paper-ice composite insulation system as a substitute for paper-LN_2 at cryogenic electric insulating system. We found that the electric breakdown strength of multi paper layer-ice composite insulation system was higher than that of the multi paper layer-LN_2 composite insulation system. It is also reported that the decreasing rate of breakdown strength occurred by conducting foreign particles with the paper-ice composite ins … More ulation system is small compared with that of the paper-LN_2 composite insulation system. In this research, the electric breakdown characteristics etc of the paper-ice composite insulating system influenced by the conducting foreign particles were investigated.The breakdown strength of OF-paper B with the metallic inclusion was higher than that of OF-A which has lower paper density in the same manner as that without the metallic inclusion. In lifetime test, it was recognized that the lifetime of the paper-ice composite insulation system with the metallic inclusion was inferior to that without the metallic inclusion while the lifetime showed almost no reduction in the paper-LN_2 composite insulation system. It was also cleared that even if the metallic inclusion existed in the paper-ice composite insulation system, the lifetime of that system under the electric field of 3 times for the partial discharge was previously excellent to that of the in the paper -LN2 composite insulation system with or without metallic inclusion. Less