热老化对交联聚乙烯电缆绝缘中水树的影响研究

热老化过程不但会影响交联聚乙烯电缆绝缘的电磁学和物理化学性能,还对绝缘内水树的产生与生长有着一定的影响。通过研究热老化过程对XLPE电缆绝缘中的水树现象的影响,以及在几个有可能的影响因素当中,哪个因素对水树现象的影响最大。实验结果表明,在与XLPE电缆绝缘的热老化有关的各种因素对水树现象的影响中,热氧化对XLPE电缆绝缘表层水树的产生和生长的影响最大。尽管热氧化所引起的缺陷有可能就是XLPE电缆绝缘中水树生长过程中的起始点,但是它在一定程度上抑制着水树的成长,甚至有着"水树延迟效果"的美称。

Investigation on Influence of Thermal Aging on Water Tree Inception in XLPE Cable Insulation

Thermal aging may influence not only the electrical,physicochemical and other properties of the XLPE cable insulation,but also the initiation and propagation of water tree inside it.This paper aims to investigate how the thermal aging influence the water tree behavior of XLPE cable insulation and which factor is the most influential to water treeing phenomena inside it.The experiment investigations on the influence of thermal degradation to the water treeing behavior of XLPE cable insulation show that thermal oxidation is the most influential to the initiation and growth of water treeing from the surface of XLPE cable insulation among all the probable factors caused during thermal aging and that thermal oxidation is observed to inhibit the growth of water tree inside XLPE insulation and to have so-called "tree-retarding effect" although it tends to provide the inception points for water treeing.