高压直流塑料电缆绝缘用纳米改性交联聚乙烯中的空间电荷特性  

Space Charge Profiles in XLPE Nano Dielectrics Used for HVDC Plastic Cable Insulation

作　　者：王霞[1] 王陈诚 朱有玉 吴锴[1] 屠德民[1] 

机构地区：[1]西安交通大学电力设备电气绝缘国家重点实验室,西安710049

出　　处：《高电压技术》2015年第4期1096-1103,共8页High Voltage Engineering

基　　金：国家自然科学基金(51377131)~~

摘　　要：为发展国产高压直流(HVDC)塑料电缆绝缘材料,削弱直流电缆运行中温度梯度效应对电缆绝缘中电场强度的畸变,针对国产纯交联聚乙烯(XLPE)、自行研发的纳米改性XLPE以及从国外进口的高压直流用XLPE等3种材料的试样进行了研究。利用电声脉冲(PEA)法和电阻率测量系统,测量了3种XLPE试样在室温、高温及温度梯度等3种温度条件下的空间电荷特性和电阻率特性。研究结果表明:在室温、高温及温度梯度等3种温度条件下,纳米改性XLPE试样在加压过程中的体内积聚电荷量最少、短路后残余电荷量较少;随着温度升高,3种XLPE试样的体积电阻率均呈下降趋势,但自行研发的纳米改性XLPE试样的体积电阻率在测试的高低温范围内始终最高,且比纯XLPE试样高出约1个数量级。因此认为在所测试的3种XLPE试样中,自行研发的纳米改性XLPE材料在测试温度范围内能最好地抑制空间电荷,拥有最高的体积电阻率。In order to develop materials for high-voltage direct-current（HVDC） plastic cables in China and to weaken the electrical field distortion in DC cable insulation induced by temperature gradient, we tested and compared three kinds of cross-linked polyethylene（XLPE）, namely, pure domestic XLPE, homemade nano-modified XLPE, and imported HVDC XLPE. Using the pulsed electro-acoustic（PEA） method and a resistivity measuring system, we measured the space charge profiles and volume resistivity of the three kinds of XLPE at different temperatures, namely, the room temperature, high temperature, and temperature gradient. The results show that, among the three kinds of XLPE, the nano-modified XLPE has the least amount of space charge when a DC stress is applied or removed at all the tested temperatures. In addition, volume resistivity of the three kinds of XLPE decreases with increasing temperature, while the nano-modified XLPE preserves the highest resistivity, about one order of magnitude higher than that of pure domestic XLPE, throughout the tested temperature range. In conclusion, the nano-modified XLPE has the best performance in inhibiting space charge as well as the highest volume resistivity in the tested temperature range.

关 键 词：高压直流 塑料电缆 纳米 交联聚乙烯 空间电荷 体积电阻率 

分 类 号：TM21[一般工业技术—材料科学与工程]