操作冲击电压下油纸针板缺陷局部放电研究  

Research on Partial Discharge of Oil-paper Insulation Needle-plate Electrode Under Switching Pulse Voltage

作　　者：聂德鑫[1] 王明渊[2] 周远翔[2] 伍志荣[1] 邓建钢[1] 张云霄[2] 

机构地区：[1]国网电力科学研究院,武汉430074 [2]清华大学电机工程与应用电子技术系电力系统及发电设备控制和仿真国家重点实验室,北京100084

出　　处：《高电压技术》2015年第3期918-924,共7页High Voltage Engineering

基　　金：国家重点基础研究发展计划(973计划)(2011CB209400);国家电网公司科技项目([2012]515)~~

摘　　要：操作冲击电压下油纸绝缘局部放电特性对于油浸式变压器的过电压防护具有重要意义。为此,采用油纸绝缘针板缺陷模拟油中电晕放电对其放电特性进行研究。通过试验和仿真手段研究其在标准操作波(波前时间250±20%μs,半峰值时间2 500±60%μs)下的放电特性,并对试验现象进行解释。试验结果表明:随着外施操作冲击电压幅值的升高,操作冲击电压上升时间内的主脉冲强度显著增强,下降时间内的局部放电信号无明显变化;随着外施操作冲击电压幅值的升高,油纸针板缺陷的初次放电时刻显著提前,初次放电时刻对应的冲击电压瞬时值显著上升;局部放电幅值(平均值、最大值)、平均放电重复率和放电脉冲数均随外施操作电压幅值的增加而增加。研究结果对于变压器的过电压防护及故障诊断有很大帮助,具有实际工程应用价值。The characteristics of partial discharge in oil-paper insulation under switching pulse is of significance to the over voltage protection of oil-immersed transformers, thus we make use of the oil-paper insulation needle-plate defect to simulate the corona discharge in transformer oil, so as to study the discharge characteristics. The characteristics of discharge within the defect under switching pulse voltage（wavefront time 250±20% μs, half peak time 2 500±60% μs） are studied through experiment and simulation. Several conclusions are summarized as follows. Firstly, with the increasing of switching pulse voltage, the variation of partial discharge waveform of the experimental model concentrates on the main impulse during the rise time of the switching pulse, which enhances significantly, while the impulse during the fall time slightly changes. Secondly, with the increasing of switching pulse voltage, the first discharge occurs ahead of time and the corresponding level of switching pulse voltage is higher. Thirdly, the max discharge capacity, mean discharge capacity, impulse numbers, and repetition rate all increase with the increasing of switching pulse voltage. The derived results are helpful to the over-voltage protection and fault diagnosis of transformers, which has practical engineering values.

关 键 词：变压器 油纸绝缘 操作冲击电压 针板缺陷 局部放电 时域波形 

分 类 号：TM855[电气工程—高电压与绝缘技术]