极性反转试验中，±800kV换流变压器套管尾部的电场分布研究  

Study on Electric Field Distribution of ±800 kV Converting Transformer Bushing Outlet Terminal during Polarity Reversal Test

作　　者：刘鹏[1] 彭宗仁[1] 党镇平[2] 罗兵 吕金壮 

机构地区：[1]西安交通大学电力设备电气绝缘国家重点实验室,西安710049 [2]西安电瓷研究所,西安710077 [3]南方电网技术研究中心,广州510623

出　　处：《电瓷避雷器》2009年第3期1-4,8,共5页Insulators and Surge Arresters

基　　金：由“十一五”国家科技支撑计划重大项目“特高压输变电系统开发与示范”课题22“±800kV直流输电系统设计规范研究”项目资助(编号:2006BAA02A22)

摘　　要：±800 kV换流变压器出线套管,是一个结构复杂的绝缘系统。在试验与运行中,套管要承受不同形式电压的作用。特别在直流极性反转的情况下,套管尾部结构复杂,电场十分集中,易发生油中闪络或击穿放电,严重威胁特高压换流变压器的安全运行。应用有限元法,仿真计算了±800 kV换流变压器出线套管尾部的电场分布,计算结果表明:在极性反转试验中,套管尾部电场分布不均匀,且不同时刻、套管尾部电场分布及各关键位置的场强变化呈现线性特性。进一步分析得知:在套管设计中,不仅要考虑正负极性反转试验电压下的稳态电场分布,还应重视极性反转过程中暂态电场与界面空间电荷效应,以便留有足够的裕度,避免在极性反转试验时套管损坏。±800 kV converting transformer bushing is a complex insulation system. In the test and operation, the bushing bears the effects of different forms of voltage. Especially when the D.C. polarity reversal, the structure is complex and the electric field distribution is concentrated at the bushing outlet terminal, so flashover or breakdown discharge in oil is easy to happen, which is a serious threat to UHV transformer, the finite element analysis is used to calculate the electric field distribution of ±800 kV converting transformer bushing outlet terminal. Calculation results show that in the polarity reversal test, the electric field distribution of bushing outlet terminal is non-uniform, and at different moments, the electric field distribution and the field strength changes with linear characteristics. Further analysis shows that in bushing design, not only have to consider the steady-state electric field distribution under ＋Upr （polarity reversal voltage）, but also should pay attention to the transient electric field and interface space charge effect during the process of polarity reversal, so that the sufficient margin shall be left to avoid bushing damage during the polarity reversal test. The research results provide basis for bushing design and standard preparing.

关 键 词：套管 电场分布 有限元法 极性反转 

分 类 号：TM42[电气工程—电器]