摘要
直流电压下气固界面绝缘的电荷积聚及其引发的沿面闪络电压下降问题是制约高电压等级直流气体绝缘设备发展的关键。研究绝缘材料对电荷诱导沿面放电的影响对高性能绝缘材料的研发,提高直流气体绝缘设备运行可靠性具有重要意义。首先搭建了气固界面电荷预置与沿面闪络实验平台,针对聚碳酸酯(polycarbonate,PC),聚甲基丙烯酸甲酯(polymethyl methacrylate,PMMA),和Al2O3掺杂的环氧树脂(epoxy resin,EP)这3种绝缘材料分别开展了电荷积聚诱导沿面放电实验,测量了绝缘材料的二次电子发射特性及陷阱分布特性,分析了绝缘材料微观参数对沿面放电的影响机理以及绝缘材料对电荷积聚诱导沿面放电的影响规律和关键影响因素。研究结果表明,正电荷的积聚抑制了正流注的发展,负电荷的积聚促进正流注的发展。绝缘材料的二次电子发射系数(secondary electron emission yield,SEEY)主要贡献于流注通道的电荷密度,而随着陷阱能级的下降,绝缘材料更容易发生沿面放电。绝缘材料的沿面流注放电通道对电场的敏感程度是决定界面电荷对沿面放电影响的重要因素。
Gas-solid interface charge accumulation and the consequent decrease in surface flashover voltage have impeded the development of DC gas-insulated equipment.Investigation of the effect of insulating material on charge-induced surface discharges holds paramount importance in advancing high-performance insulation and enhancing the operational reliability of DC gas-insulated equipment.In this paper,an experimental platform for charge spot deposition and surface discharge is established.Then,the charge-induced surface discharge for three types of insulating materials,including polycarbonate(PC),polymethyl methacrylate(PMMA),and epoxy resin(EP)doped with Al2O3,are conducted.Additionally,the secondary electron emission yield(SEEY)and trap distribution of the insulating materials are measured,and the effect pattern and key factors of insulating materials on charge-induced surface discharges are obtained,along with the influence mechanism of microscopic parameters of insulating materials on surface discharge.The results indicate that the deposited positive charges inhibit the development of positive streamers,while deposited negative charges promote the development of positive streamers.Furthermore,the secondary electron emission yield of insulating materials mainly contributes to the residual charge density of streamer.As the trap energy level decreases,surface discharge in the insulating material becomes more likely.The sensitivity of streamer channels of insulation surface to the electric field is a crucial factor determining the effect of interface charges on surface discharge.
作者
李奕萱
张博雅
陶海斐
李杰
袁宵
李兴文
LI Yixuan;ZHANG Boya;TAO Haifei;LI Jie;YUAN Xiao;LI Xingwen(State Key Lab of Electrical Insulation and Power Equipment(Xi’an Jiaotong University),Xi’an 710049,Shaanxi Province,China)
出处
《中国电机工程学报》
北大核心
2025年第17期6968-6978,I0030,共12页
PROCEEDINGS OF THE CHINESE SOCIETY FOR ELECTRICAL ENGINEERING
基金
国家自然科学基金项目(U23B20132)。
关键词
雷电冲击电压
气固界面电荷
沿面放电
绝缘材料
电荷分布
lightning impulse voltage
gas-solid interface charge
surface flashover
polymers
surface charge distribution
