中文摘要：

为研究添加炭黑（CB）对交联聚乙烯（XLPE）绝缘材料直流介电性能的影响,通过熔融共混制备了CB/XLPE纳米复合材料,在不同的恒定温度下分别测试了各试样的电导率与外施直流电场强度的关系,并利用电声脉冲法测量了各试样内的空间电荷分布状况。研究结果表明,添加少量炭黑即可使XLPE中的空间电荷量明显减少,当炭黑掺量为1 phr（指每100 g XLPE中添加1 g CB）时,复合材料抑制空间电荷的能力较强;XLPE在较低电场强度下就表现出电导非线性特性,且电导率受温度影响较大,最大变化量超过3个数量级;而CB/XLPE纳米复合材料在小于20 kV/mm的电场强度下电导率变化较小,且温度对其直流电导率的影响明显小于XLPE。炭黑能抑制XLPE中空间电荷累积和改善其直流电导特性的原因是增大了材料中的陷阱密度和陷阱深度。

英文摘要：

In order to investigate the effect of addictive carbon black （CB） on the DC dielectric properties of cross-linked polyethylene （XLPE）, we fabricated CB/XLPE nanocomposite samples using the melt blending method, tested the rela- tionship between the electrical conductivity and the applied DC electric field strength of the sampes under various temperatures, and used the pulsed electro-acoustic method to measure the space charge distribution in XLPE and the sam- pies. The research results show that a small amount of addictive of CB can significantly reduce the space charge inside XLPE. When the CB content in XLPE is 1 phr （adding 1 g CB to every 100 g XLPE）, the CB/XLPE nanocomposite has the best ability of inhibiting space charge. XLPE exhibits nonlinear conductive characteristics at relatively low electric field strength. Its conductivity is strongly affected by temperature, and the variation can reach up to three orders of mag- nitude. In contrast, the electrical conductivity of CB/XLPE nanocomposites is almost constant under electrical field no stronger than 20 kV/mm, and it is affected by temperature obviously less compared with that of XLPE. It is concluded that the addictive CB inhibits the space charge accumulation and improves the DC conductivity property for XLPE be- cause it increases the trap density and depth in the CB/XLPE nanocomposites.