摘要
换流变压器阀侧干式套管采用表带触指作为导体的连接和载流结构,随着输送功率的提高,套管载流量不断提升,插接结构的接触电阻发热将影响套管的可靠运行。针对±500kV换流变阀侧干式套管,通过三维有限元分析耦合电磁、热、流等多物理场,考虑热传导、热对流和热辐射的影响,计算分析了插接结构发热情况下套管的温度场分布以及接触电阻不同程度劣化对套管热场分布的影响。结果表明:接触电阻劣化会引起插接结构局部过热,最终导致环氧芯体与导电管界面温度上升,影响套管安全稳定运行。同时,研究发现导电管温升与复合硅橡胶外套表面温升具有线性相关性,通过红外热像仪探测复合外套表面温度能够有效推测套管内部过热情况。该研究获得了套管温度场分布规律及接触电阻劣化后引起的过热性故障机理,相关成果可为运行单位提供在线监测依据。
Watchband contact fingers are taken as connecting structure for the conduct converter transfomer RIP bushings.With the increase of transmission power and current carrying of bushings,overheating problem of plug-in structure due to the existence of contact resistance has become a bottleneck for the safe and stable operation of converter transformer RIP bushings.Taking 500 kV converter transformer RIP bushings as research subject,a 3D coupled electromaggnetic-thermal-fluid analysis method has been adopted;processes including heat radiation,heat conduction and heat convection has been taken into account;the temperature field of 500 kV convector transformer bushing considering contact resistence heating effect and its degradation have been calculated and analyzed.The results indicate that the degradation of contact resistatnce will lead to the partial overheating in plug-in structure and result in the temperature increase on interface between conductor and RIP core,which finally threat the safe and stable operation of power system.Meanwhile,this research found that the temperature of conductor and sheath perform linear correlation,detecting the temperature on sheath by infrared camera can effectively infer the temperature of conductor.This research obtained the temperature distribution law of bushings and the mechanism of overheating fault caused by degradation of contact resistance,which provides basis of bushings on-line monitoring for operation department.
作者
张晋寅
田汇冬
吴泽华
周仕贻
史然
刘鹏
彭宗仁
ZHANG Jinyin;TIAN Huidong;WU Zehua;ZHOU Shiyi;SHI Ran;LIU Peng;PENG Zongren(Department of SHV Maintenance and Test of China Southern Power Grid,Guangzhou 510623,China;Xi'an Jiaotong University,Xi'an 710049,China)
出处
《电瓷避雷器》
CAS
北大核心
2019年第5期200-206,共7页
Insulators and Surge Arresters
基金
中国南方电网有限责任公司超高压输电公司检修试验中心《交直流套管载流连接结构的热场分析与缺陷诊断技术》研究项目
关键词
换流变阀侧干式套管
接触电阻
温度分布
耦合场
过热性故障
convector transformer bushings
contact resistance
temperature distribution
coupled field
overheating fault