高电压技术2023，Vol.49Issue(12)：4938-4947,10.DOI:10.13336/j.1003-6520.hve.20221466
直流电压下油纸复合绝缘电场分布对击穿特性的影响
Influence of Electric Field Distribution on Breakdown Characteristics of Oil-paper Composite Insulation Under DC Voltage
摘要
Abstract
Breakdown of oil-paper composite insulation is one of the main insulation faults of converter transformer.The quantitative relationship between electric field distribution and breakdown characteristics of oil-paper composite insula-tion is rarely studied.In this paper,the electric field distribution and breakdown characteristics of oil paper composite insulation are adjusted by TiO2 nanoparticles.The electric field distribution in oil-paper composite insulation is measured by a pulsed electro-acoustic method.A combined measurement platform of light and current for breakdown process based on photomultiplier tube and Rogowski coil is built,and an equivalent model of oil-paper composite insulation with ex-tended Debye model and interface potential barrier limiting current is proposed.The results show that the interface charge density is increased by the relaxation polarization process and shallow traps introduced by nanoparticles,thereby the time difference of light and current signal and the polarity effect of breakdown voltage in the breakdown process of oil paper composite insulation are completely opposite to the original.The reason is that the initiation position of breakdown is dif-ferent due to the change of electric field distribution of oil paper composite insulation.The proposed model can better reflect the relationship among the polarity effects of polarization current,electric field distribution and breakdown voltage of sandwich dielectric.And the calculated results are in good agreement with the measured results,which verifies the ef-fectiveness of the model.The result can provide guidance for the insulation structure design of converter transformer and the modification of oil-paper composite insulation materials.关键词
油纸绝缘/界面势垒/光电联合/Dcbye模型/电场分布/击穿/TiO2粒子Key words
oil-paper insulation/interface barrier/combined measurement of light and current/debye model/electric field distribution/breakdown/TiO2 nanoparticle引用本文复制引用
宋翰林,黄猛,姚园鑫,尤玮光,应宇鹏,吕玉珍..直流电压下油纸复合绝缘电场分布对击穿特性的影响[J].高电压技术,2023,49(12):4938-4947,10.基金项目
北京市自然科学基金(3212035) （3212035）
国家自然科学基金联合基金(U1866603).Project supported by Beijing Natural Science Foundation(3212035),Joint Funds ofNational Natural Science Foundation of China(U1866603). （U1866603）
