商用直流电缆料采用不同质量分数纳米MgO改性选型

Selection of Commercial DC Cable Material for Modification by Nano-MgO with Different Loading Content

为提高商用直流电缆料高温下的绝缘性能,向商用直流电缆料添加不同质量分数的纳米MgO粒子,制备了MgO/XLPE纳米复合介质,并测试了试样在不同温度下的正、负极性直流击穿场强、空间电荷分布以及电导率。结果表明：添加纳米MgO粒子能显著提升直流电缆料正、负极性直流击穿场强,添加质量分数为0.1%和0.5%的纳米MgO粒子能减小温度对电导率和空间电荷特性的影响,提高其高温下的电导率和空间电荷性能,减少直流电缆中的电场畸变。经综合比较可选用添加质量分数0.1%纳米MgO粒子来改性现有商用直流电缆料。

In order to improve the insulation characteristics of commercial DC cables＇ material under high temperatures, the nanocomposite specimens were fabricated through adding different mass fraction（0.1%, 0.5%, 1%） of nano MgO to materials of commercial DC cables. The positive and negative DC breakdown strength, the space charge distribution of specimen and the conductivity were tested under different temperatures. The results show that the addition of nano-MgO can obviously improve the DC breakdown strength. Adding 0.1% and 0.5% nano-MgO to materials of DC cables can reduce the influences of temperature on the conductivity and the space charge characteristics, improve the electrical conductivity and space charge properties under high temperature, and reduce the electric field distortion in the DC cables. After comprehensive comparison, the 0.1% adding content of nano-MgO is more effective in improving the insulation characteristics of commercial DC cable materials.