抗水树交联电缆运行安全性研究

Study on Operating Safety of Anti-watertreeing XLPE Cable

为降低水树在中、高压电缆运行过程中的生长速度,将乙烯丙烯酸(EAA)共聚物、二亚苄基山梨糖醇(DBS)助剂加入交联聚乙烯(XLPE)基料中合成新型电缆绝缘料配方。在160℃进行混合、压片使之完成交联反应后,采用水树培养、电加速电老化试验研究添加剂含量对水树枝长度的影响。试验结果表明,在200倍偏光显微镜下可明显观察到改性后的电缆绝缘料中水树枝长度在一定范围内随着EAA及DBS含量的增加而减小,EAA及DBS在绝缘料中最佳的混合份数分别为1.5份和0.6份,抗水树交联电缆运行安全得到有效提高。

Growth rate of water tree in medium and high voltage cable was inhibited by adding EAA, DBS into cross-linked polyethylene （XLPE）-based materials. The mixture was crosslinked through mixing and tabletting the blend at 160 ℃. The effect of additive content on the length of the water tree was inves- tigated by polarized light microscope, water tree cultivation experiment and accelerated electrical aging test. The results show that the length of water tree decreases with increasing of the content of EAA and DBS in the modified cable insulation compound within a certain range and that the most appropriate content of EAA and that of DBS were 1.5 phr and 0. 6 phr respectively. Operating safety of anti-watertreeing XLPE cable was greatly improved.