直流电老化低密度聚乙烯的空间电荷陷阱特征  

Trapping characteristics of low density polyethylene under DC ageing by space charge

作　　者：廖瑞金[1] 聂仕军[1,2] 周天春[3] 杨丽君[1] 袁磊[1] 

机构地区：[1]重庆大学输配电装备及系统安全与新技术国家重点实验室,重庆400030 [2]国网长沙供电公司,长沙410000 [3]电力规划设计总院,北京100120

出　　处：《重庆大学学报（自然科学版）》2013年第9期78-82,共5页Journal of Chongqing University

基　　金：国家重点基础研究发展计划项目(2011CB209401);国家创新研究群体基金资助项目(51021005);输配电装备及系统安全与新技术国家重点实验室自主研究项目(2007DA10512710401)

摘　　要：高压直流电缆绝缘材料的老化与空间电荷有密切关系,探索一种能够表征材料老化程度的空间电荷特征参量显得尤为重要。笔者以低密度聚乙烯(LDPE)材料为例,使用电声脉冲法(PEA)研究了直流电老化程度对空间电荷陷阱特征的影响,提出一种离散分布的空间电荷陷阱模型,并基于此模型计算出陷阱特征参数(陷阱深度和陷阱密度)。结果表明随着直流电老化程度的增大,样品内较浅陷阱转化为较深陷阱,并得到老化程度与陷阱深度、陷阱密度的关系,为聚合物材料老化诊断提供参考。Space charge in insulation material of high voltage direct current cable is closely linked with the ageing degree of the materials, and it is an interesting topic if one can find some characteristics to indicate the ageing of the material from the space charge measurement. In this paper, the effects of ageing on space charge characteristics of low density polyethylene （LDPE） are investigated by the pulsed electro-acoustic （PEA） method. A space charge trapping model is proposed base on distribution of discrete traps, and the characteristic parameters in the model including trap depth and trap density are calculated. The results show that the relatively shallow traps in the samples transform to the relatively deep traps as the degree of electrical ageing increases. Furthermore, the relationships between ageing degrees and trap depth and trap density are obtained. The information of the trapping parameters in our model provides a good reference for diagnosing the ageing degree of polymeric materials.

关 键 词：聚乙烯 空间电荷 陷阱 电老化 电缆 直流输电 

分 类 号：TM201.3[一般工业技术—材料科学与工程]