不同气压下XLPE电缆水树生长特性

Growth characteristics of XLPE cable water tree under different air pressures

为了探究气压对交联聚乙烯(XLPE)电缆水树枝生长特性的影响,选用不同气压环境对XLPE电缆进行水树老化,基于水针电极法搭建气压环境电缆的水树老化平台并进行老化。从宏观介电性能测试与微观形貌检测相结合的角度,分析XLPE电缆在不同条件下水树枝的生长特性。对不同气压环境老化后的电缆进行宏观微观测试,发现在老化初期,气压条件对电缆水树老化的促进作用很小,到了老化中期,随着气压的升高,电缆水树老化程度也随之升高。将不同条件下老化后电缆的宏观测试结果与微观测试结果相结合,得到使用直流电导率、0.1 Hz介质损耗因数及老化因子对XLPE电缆内部水树密度的预测模型,实现了对不同条件下老化后电缆水树老化程度的无损检测。微观检测结果表明,气压环境在老化前期对水树生长无明显作用,老化后期对水树生长起促进作用。

In order to explore the influence of air pressure on the growth characteristics of water branches of cross-linked polyethylene(XLPE)cable,different air pressure environments were selected to age the water tree of XLPE cable,and a water tree aging platform for air pressure environment cable was built based on the water needle electrode method and ages.From the perspective of combining macroscopic di-electric performance test and microscopic morphology detection,the growth characteristics of water bran-ches of XLPE cable under different conditions were analyzed.The macroscopic test of the aging cable un-der different air pressure environment shows that in the early stage of aging,the air pressure conditions have little effect on the aging of cable water trees,and in the middle of aging,with the increase of air pressure,the aging degree of cable water trees also increases.By combining the macroscopic test results and microscopic test results of aging cables under different conditions,a prediction model of the internal water tree density of XLPE cable using DC conductivity,0.1 Hz dielectric loss factor and aging factor was obtained,and the non-destructive testing of the aging degree of cable water tree after aging under different conditions was realized.The microscopic test results show that the barometric environment had no obvious effect on the growth of water trees in the early stage of aging,and promoted the growth of water trees in the late aging stage.