交联聚乙烯电缆热老化与电树枝化相关性研究

热老化过程不但会影响交联聚乙烯（XLPE）电缆绝缘的物理化学性能，还对绝缘内电树的产生与生长有着一定的影响。研究了热老化后XLPE电缆绝缘中的电树行为．探讨XLPE电缆绝缘中电树枝过程与材料热老化的关系。采用带循环通风的热老化箱对XLPE电缆绝缘进行3个温度等级的热老化实验：采用针板结构电极进行电树枝实验，并利用数码显微镜观察电树枝的产生和发展情况；利用差示扫描量热法（DSC）、傅里叶红外光谱分析（FTIR）测试了不同温度热老化下XLPE电缆绝缘的物理化学性能；最后探讨了几种不同结构电树枝的生长机理．认为热老化并没有加速电树枝的生长．反而有一定的抑制作用．

Research on Correlation Between Thermal Aging and Electrical Treeing of Cross-Linked Polyethylene Cable

Thermal aging may influence not only physiochemical performance of cross-linked polyethylene cable＇s insulation but also the initiation and propagation of electrical tree. The behavior of electrical tree after long time thermal aging of cable insulation is studied, and the relationship between thermal aging and electrical treeing in XLPE cable insulation is discussed. Thermal aging test were carried out at three levels of temperature 120℃ , 140℃ and 160 ℃. Needle-board structure electrode was used to cause electrical trees and electron microscope was used to watch initiation and growth of trees. The physicochemical characteristics of XLPE cable insulation after thermal aging at different temperature were tested by DSC and FTIR. The results show that the increasing of polar groups and the degradation of macromolecules, resulting from the thermal oxidation of XLPE cable insulation in thermal aging test, lead to more unhomogeneous structure of the material. Finally, the growth principles of several different type trees are discussed. The conclusion is drawn that thermal aging does not accelerate the growth of electrical treeing ,but retard it.