基于纳米SiO_2复合填充的交联聚乙烯电缆水树修复新技术

A New Rejuvenation Technology Based on Formation of Nano-SiO_2 Composite Fillers for Water Tree Aged XLPE Cables

提出了一种在水树通道内自生成纳米Si O2复合填充物的电缆修复液,并将其修复效果与先期纳米修复液作了对比。采用水针电极法加速交联聚乙烯(XLPE)电缆绝缘水树老化,利用两种不同成分的纳米修复液对老化电缆样本进行修复。介质损耗和工频击穿电压测试结果表明,该新型修复液修复后样本绝缘性能提升更大。对修复前后的水树样本进行显微镜观测,证实了生成物对水树通道的填充效果。通过对修复液与水直接反应生成物和电缆样本击穿通道进行扫描电镜(SEM)分析,可看到新型修复液生成的纳米Si O2粒径更小,修复后电缆样本击穿通道内部的无机纳米颗粒团聚程度更低,分布更均匀。基于以上发现,证明了该新型修复液能够在水树通道内自生成纳米Si O2复合填充物,且修复效果优于先期纳米修复液,并提出了偶联剂界面连接模型对实验结果进行了解释。

A new rejuvenation liquid toward forming nano-SiO2 composite fillers inside water tree channels was presented, and the rejuvenation performance of the reformulation was compared with that of previous formulation. A water-needle method was employed to obtain water tree aged cables, and the cables were injected with two groups of nano rejuvenation liquids. Dielectric loss factor（tanδ） and AC breakdown tests show that the reformulation leads to a greater increase in cable insulation performance than the previous formulation. Microscope observation proved that there are fillers in the water tree channels after rejuvenation. By a scanning electron microscope（SEM） analysis, nano SiO2 particles are observed smaller than Ti O2, and the SiO2 particles are more uniformly embed in the XLPE matrix inside the breakdown channels of the rejuvenated cables. According to the results, it shows that the new rejuvenation liquid can form nano-SiO2 composite fillers inside water tree channels, and the reformulation has better rejuvenation performance than the previous formulation. Furthermore, a coupling model was presented, based on which the experimental results were explained.