直流预压对针板电极下XLPE中空间电荷及电树枝的影响  

Effect of DC Pre-stress on Space Charge and Electrical Tree in XLPE with Needle-Plate Electrodes

作　　者：徐晓彬 刘爱静 乐彦杰 刘贺晨[1] 郭展鹏 刘云鹏[1] XU Xiaobin;LIU Aijing;LE Yanjie;LIU Hechen;GUO Zhanpeng;LIU Yunpeng(North China Electric Power University,Hebei Provincial Key Laboratory of Power Transmission Equipment Security Defense,Baoding 071003,China;State Grid Zhejiang Electric Power Company Zhoushan Power Supply Company,Zhoushan 316000,China)

机构地区：[1]华北电力大学河北省输变电设备安全防御重点实验室,河北保定071003 [2]国网浙江省电力公司舟山供电公司,浙江舟山316000

出　　处：《中国电力》2021年第4期56-62,71,共8页Electric Power

基　　金：电网环境保护国家重点实验室开发基金资助项目(GYW51201901087);河北省自然科学基金资助项目(E2018502133);中央高校基本科研业务费专项资金资助项目(2018MS079);国家重点研发计划资助项目(2016YFB0900705)。

摘　　要：空间电荷是影响高压直流电缆绝缘电树枝特性的主要原因之一。基于双极性载流子输运模型,对±20kV、±22.5kV和±25kV直流预压下3600 s内二维针板电极模型空间电荷分布进行仿真分析,并对比分析空间电荷分布与直流接地电树枝引发特性。结果表明:空间电荷浓度及注入深度随预压幅值及时间的增加而增大;直流接地电树枝引发长度随预压时间及幅值的增加而增加。空间电荷注入深度与电树枝引发长度两者之间高度相似。接地电树枝引发特性存在差异的主要原因是针尖附近空间电荷的分布特性。Space charge is one of the main factors that affect the electrical tree characteristics of HVDC cable insulation.Based on the bipolar charge transport model,this paper simulates the space charge distribution characteristics of the two-dimensional needle plate electrode model under±20 kV、±22.5 kV and±25 kV DC pre-stress with a duration of 3600s,and makes a comparative analysis between the space charge distribution characteristics and the DC grounded electrical tree initiation characteristics.The results show that the space charge density and injection depth increase with the increase of the pre-stress and time,and the initiation length of DC grounded electrical tree increases with the increase of pre-stress duration and amplitude.There is a high similarity between space charge distribution characteristics and electrical tree initiation characteristics.The space charge distribution near the needle tip is the main reason for the difference in the initiation characteristics of the grounded electrical tree.

关 键 词：空间电荷 直流预压 交联聚乙烯 双极性载流子输运模型 COMSOL 极性效应 

分 类 号：TM721.1[电气工程—电力系统及自动化] TM247[一般工业技术—材料科学与工程]