半导电屏蔽材料对高压XLPE电缆绝缘电气性能的影响

Influence of semiconductive shielding material on electrical properties of high voltage XLPE cable insulation

为研究半导电屏蔽材料对高压XLPE电缆绝缘中电荷输运行为的影响,本研究选用国内外3种不同型号的半导电屏蔽材料配合同一XLPE绝缘,模拟实际电缆结构试制了屏蔽-绝缘-屏蔽的三明治结构试样,并对其进行高场强电导测试以及空间电荷测量。结果表明:屏蔽层的引入使绝缘内部的电导方式发生了改变。相较于纯XLPE绝缘试样,含屏蔽层配合的绝缘试样电荷注入明显增加,其中进口屏蔽料配合的试样绝缘-屏蔽界面对电荷注入的抑制能力较强,电荷注入程度较弱。电荷注入会对空间电荷在绝缘内部的积聚程度产生影响,其中,含国产屏蔽料配合的试样的空间电荷积聚较为严重,含进口屏蔽料配合的试样空间电荷积聚程度较轻。此外,空间电荷测量还需要注意因试样结构的特殊性带来的阻抗不匹配问题。

In order to study the influence of semi-conductive shielding materials on the charge transport behavior in insulation,we selected three different types of semi-conductive shielding materials made in and out of China to cooperate with the same insulation,and trial-produce a shield-insulation-shield sandwich structure sample by simulating the actual cable structure,and conducted high-field conductance tests and space charge measurements.The results show that the introduction of the shielding layer changes the conduction mode inside the insulation.Compared with the pure insulation sample,the charge injection of the insulation sample with shielding layer increases significantly.The insulation-shielding interface of the imported shielding material sample has a stronger ability to inhibit charge injection,and the charge injection degree is weaker.The measurement of the space charge of each sample shows the impact of charge injection on the degree of space charge accumulation inside the insulation,the space charge accumulation of the shielding material sample made in China is more serious,while that of the imported sample is lower.It is needed to concern the impedance mismatch problem caused by the particularity of the sample structure in the measurement of space charge.