摘要
直流电场下,电缆绝缘中的温度梯度效应导致绝缘材料空间电荷行为复杂,影响电缆系统长期运行的可靠性。目前,温度梯度下电缆绝缘空间电荷特性的研究多集中于平板结构的切片试样,但平板结构切片试样的空间电荷测量能否反映真实电缆绝缘中的空间电荷特性尚缺乏有力证明。该研究测量并分析了温度梯度场下2种不同结构(同轴结构、平板结构)10 kV交联聚乙烯(cross-linked polyethylene,XLPE)试样的空间电荷演变特性以及电场分布行为,基于去压状态下的空间电荷行为,计算了XLPE同轴电缆和切片试样的载流子迁移率以及陷阱深度分布,并对2种结构XLPE试样的空间电荷行为和电荷特性参数进行了对比性研究。该研究结果表明同轴结构和温度梯度效应均会加剧XLPE电缆外半导电层附近的空间电荷积聚,除了结构因素的影响,温度梯度场下XLPE同轴电缆和平板切片试样的空间电荷演变规律以及电荷特性参数均呈现出等效规律。
Under the direct current(DC)electrical stress,a temperature gradient effect inside cable insulation may complicate the space charge behavior,which affects the cable system long-term operation reliability.Still now,researches on space charge under temperature gradient focus on sliced specimens.However,it is questionable whether the results of a flat sample can reflect the charge characteristics in an actual coaxial cable.In this paper,the space charge evolution characteristics and electric field distributions for the two different structures(coaxial and flat)10 kV cross-linked polyethylene(XLPE)cables were researched under a temperature gradient.Mobility and trap depth distributions were calculated through the charge depolarization waveforms,and the space charge behaviors and charge characteristics parameters for the two structures samples were comparatively studied.The results show both the coaxial structure and temperature gradient add the charge accumulation near the outer semi-conductor of cables.Except for the influence of structural factors,space charge behaviors and charge characteristics parameters for the two samples under temperature gradient show a basic equivalence.
作者
陈驰
王霞
吴锴
成传晖
王闯
CHEN Chi;WANG Xia;WU Kai;CHENG Chuanhui;WANG Chuang(School of Electrical Engineering,Xi’an University of Technology,Xi’an 710048,China;State Key Laboratory of Electricial Insulation and Power Equipment,Xi’an Jiaotong University,Xi’an 710049,China;Electric Power Research Institute,China Southern Power Grid,Guangzhou 510663,China)
出处
《高电压技术》
EI
CAS
CSCD
北大核心
2021年第11期4078-4086,共9页
High Voltage Engineering
基金
国家自然科学基金(51707155)。
关键词
同轴电缆
空间电荷
等效性
温度梯度
异极性电荷
coaxial cable
space charge
equivalence
temperature gradient
hetero-charge
