不同极性乙烯-醋酸乙烯酯共聚物对低密度聚乙烯共混体系电性能的影响  

Effect of Ethylene-vinyl Acetate Copolymer with Different Polarities on Electrical Properties of Low Density Polyethylene Blends

作　　者：翟近涛 查俊伟[1,2,3] 卞星明 党智敏 ZHAI Jintao;ZHA Junwei;BIAN Xingming;DANG Zhimin(School of Chemistry and Biological Engineering,University of Science and Technology Beijing,Beijing 100083,China;Department of Electrical Engineering,Tsinghua University,Beijing 100084,China;State Key Laboratory for Alternate Electrical Power System with Renewable Energy Sources,North China Electric Power University,Beijing 102206,China)

机构地区：[1]北京科技大学化学与生物工程学院,北京100083 [2]清华大学电机工程与应用电子技术系,北京100084 [3]新能源电力系统国家重点实验室(华北电力大学),北京102206

出　　处：《广东电力》2019年第12期19-25,共7页Guangdong Electric Power

基　　金：国家自然科学基金项目(51622701);国家重点基础研究发展计划(973计划)项目(2014CB239501);新能源电力系统国家重点实验室开放课题(LAPS19001)

摘　　要：低密度聚乙烯(LDPE)具备优良的化学稳定性和电气绝缘性加工性,常常用作高压绝缘电缆材料,但是,LDPE在高压直流电场下的运行过程中也会面临诸多问题,其中最突出的问题是空间电荷在绝缘材料中的积聚行为。针对此,选取2种不同牌号的乙烯醋酸乙烯酯共聚物(EVA),采用熔融共混法改性LDPE基体,通过结晶行为和陷阱特性研究LDPE/EVA共混体系的空间电荷积聚行为和直流击穿强度。结果表明:对比纯LDPE,2种共混物都消除了空间电荷包现象,其中LDPE/EVA 18-150共混物直流击穿强度提高至329 kV/mm;由此说明,添加EVA填料在提高材料的电绝缘性能方面具有潜在的应用价值。Low density polyethylene(LDPE)is often used as the insulation material for high voltage cables due to its excellent chemical stability and electrical insulation processability,but it also may face many problems in operation under the HVDC field and the most prominent problem is accumulation behavior of space charge in the insulation material.Thus,two different grades of ethylene-vinyl acetate copolymer(EVA)with different polarities were selected to modify the LDPE by means of melt blending method,and the accumulation behavior of space charge and DC breakdown strength of the LDPE/EVA blends were investigated according to crystallization behavior and trap characteristics.The results indicate compared with pure LDPE,these two blends both eliminate space charge packet phenomenon,and the DC breakdown strength of LDPE/EVA 28-150 blend increases to 329 kV/mm.From this,the addition of EVA fillers has great potential in improving electrical insulation properties of materials.

关 键 词：LDPE/EVA共混 结晶行为 陷阱特性 空间电荷 直流击穿强度 

分 类 号：TM215.1[一般工业技术—材料科学与工程]