高电压技术2018，Vol.44Issue(8)：2664-2671,8.DOI:10.13336/j.1003-6520.hve.20180619004
交联聚乙烯直流电缆料高温空间电荷行为特性
Space Charge Behavior of DC Cable's XLPE Material at High Temperatures
摘要
Abstract
In order to study the space charge behavior of imported DC cable's XLPE material at high temperatures, we prepared undegassed and degassed XLPE samples for the tests, including DC conduction, dielectric and space charge during steady and transient processes at high temperatures. The results show that both the conduction current and dielectric loss of undegassed XLPE are larger than those of degassed XLPE. Negative charge accumulation is observed in the bulk of degassed and undegassed XLPE under-30 MV/m, and the distortion ratio of internal electric fields is below 25％ at 30 ℃ and 70 ℃. A positive space charge packet appears and subsequently moves quickly within the first 2 s polarization under-100 MV/m at 70 ℃. However, the injection and migration of a negative space charge packet can only be observed when the applied field raises to-150 MV/m. Here, both polarities of space charge packets follow negative differential mobility. The analyses reveal that degassing treatment can effectively reduce the amount of crosslinking byproducts in XLPE, resulting in the decrease of ionization and conductivity in low frequency regions. A small amount of negative charge accumulating in the bulk is produced mainly by the ionization of crosslinking byproducts and impurities, but the positive charge is injected from the anode with the increase of electric field, and the rate of impurity ionization is higher than the positive charge injection rate. During the initial stage of polarization processes under-150 MV/m at 70 ℃, the fast transit of positive charge leads to the severe distortion of the local field near the cathode (up to 61.5％), resulting in a large amount of negative charge injection and the formation of a negative space charge packet in the bulk.关键词
直流电缆/交联聚乙烯/空间电荷/高温/暂态过程Key words
DC cable/XLPE/space charge/high temperature/transient process引用本文复制引用
程子霞,鲁泽楷,张灵,周远翔,张云霄,陈铮铮..交联聚乙烯直流电缆料高温空间电荷行为特性[J].高电压技术,2018,44(8):2664-2671,8.基金项目
国家重点基础研究发展计划(973计划)(2014CB239501) （973计划）
国家自然科学基金(51707100 （）
51377089) （）
中国博士后科学基金(2016M591176 （）
2017T100079) （）
河南省国际科技合作计划(162102410072).Project supported by National Basic Research Program of China(973 Program)(2014CB239501), National Natural Science Foundation of China(51707100, 51377089), China Postdoctoral Science Foundation(2016M591176, 2017T100079), International Science & Technology Cooperation Project of Henan Province of China(162102410072). （162102410072）
