冲击电压下温度对油中电场时空分布的影响  

Effect of Temperature on Electric Field Space-time Distribution in Oil Under Impulse Voltage

作　　者：苑清[1] 齐波 李成榕 高春嘉 赵晓林 张书琦 YUAN Qing;QI Bo;LI Chengrong;GAO Chunjia;ZHAO Xiaolin;ZHANG Shuqi(Beijing Key Laboratory of High Voltage&Electromagnetic Compatibility,North China Electric Power University,Beijing 102206,China;State Key Laboratory of Alternate Electrical Power System with Renewable Energy Sources,North China Electric Power University,Beijing 102206,China;China Electric Power Research Institute,Beijing 100192,China)

机构地区：[1]高电压与电磁兼容北京市重点实验室(华北电力大学),北京102206 [2]新能源电力系统国家重点实验室(华北电力大学),北京102206 [3]中国电力科学研究院有限公司,北京100192

出　　处：《高电压技术》2020年第9期3187-3193,共7页High Voltage Engineering

基　　金：国家重点研究发展计划(2017YFB0902704);国家自然科学基金(51477052);国家电网公司科技项目(GY71-18-052)。

摘　　要：冲击电压下油中空间电场分布对于变压器内部绝缘优化设计至关重要,现有设计方法未考虑空间电荷作用和温度影响。为了研究空间电荷和温度对油中电场的影响,搭建了温度可控的冲击电压下油中电场测量平台,测量了雷电冲击电压下25、50、60℃平板电极油中空间电场分布随时间和空间的变化规律。实验结果表明:随着温度的增加,油中场强的最大值呈下降趋势,60℃时油中场强峰值比25℃时下降了5.2%;随着温度的增加,油中空间电场的分布逐渐均匀,25℃下0.36μs时油中实测空间场强最大、最小值相差3.2 kV/mm,50℃下0.36μs时相差值为0.7 kV/mm,且50℃下0.60μs时油中场强分布均达到稳定阶段。通过测量油中的电子漂移速度发现,50、60℃下的电子平均漂移速度分别是25℃下的1.3、1.8倍,温度引起电子漂移速度的增加是导致上述现象的主要原因。The distribution of spatial electric field in the oil under the impulse voltage is important for optimization design of transformer insulation.The effects of space charge and temperature have not been taken into account in now available design methods.Consequently,in order to study the effects of space charge and temperature on the electric field in oil,an electric field measurement platform under impulse voltage where the temperature is controllable is built,.The variation of spatial electric field distribution in oil with plate electrode at 25,50 and 60℃under lightning impulse voltage is measured with time and space.The results show that,as the temperature increases,the maximum field strength decreases.The peak electric field strength at 60℃has decreased by 5.2%compared with it at 25℃.As the temperature increases,the distribution of the spatial electric field in oil gradually becomes uniform.The discrepancy of maximum and minimum measured spatial field strengths is 3.2 kV/mm at 0.36μs under 25℃,and the discrepancy between maximum and minimum measured spatial field strengths is 0.7 kV/mm at 0.36μs under 50℃.The field strength distribution in oil reaches the stable stage at 0.60μs under 50℃.By measuring the electron drift velocity,it is found that the average drift velocities of electrons at 50 and 60℃are 1.3 and 1.8 times that at 25℃,respectively.The increase in electron drift velocity caused by temperature primarily generates the above phenomenon.

关 键 词：油中电场 空间电荷 时空分布 温度 KERR效应 冲击电压 

分 类 号：TM855[电气工程—高电压与绝缘技术]