稍不均匀场中负极性振荡型操作冲击电压下的变压器油击穿特性  

Breakdown Characteristics of Transformer Oil Under Negative Oscillating Switching Impulse in Non-uniform Electric Field

作　　者：孙文星 杨贤 肖祥 蔡玲珑 马志钦 孙善源 李军浩[4] SUN Wenxing;YANG Xian;XIAO Xiang;CAI Linglong;MA Zhiqin;SUN Shanyuan;LI Junhao(Guangdong Power Grid Co.,Ltd.,Guangzhou 510080,China;Electric Power Research Institute of Guangdong Power Grid Co.,Ltd.,Guangzhou 510000,China;Guangdong Key Laboratory of Electric Power Equipment Reliability,Guangzhou 510080,China;State Key Laboratory of Electrical Insulation and Power Equipment,Xi'an Jiaotong University,Xi'an 710049,China)

机构地区：[1]广东电网有限责任公司,广州510080 [2]广东电网有限责任公司电力科学研究院,广州510000 [3]广东省电力装备可靠性企业重点实验室,广州510080 [4]西安交通大学电力设备电气绝缘国家重点实验室,西安710049

出　　处：《高电压技术》2021年第7期2545-2552,共8页High Voltage Engineering

基　　金：中国南方电网有限责任公司科技项目(GDKJXM20172901)。

摘　　要：操作冲击电压对电力变压器的侵袭频率高于雷电冲击电压。目前针对振荡型操作冲击电压和标准操作冲击电压下变压器油击穿特性研究较少,振荡波形更符合工况实际波形。为此采用3、6、12 kHz 3种频率的负极性振荡操作冲击电压(OSI)和标准操作冲击电压(SI),以间距2.5 mm的板-板电极构成稍不均匀电场模型,研究该电场下变压器油在操作冲击电压下的击穿特性,记录了这3种频率的振荡操作冲击电压和标准操作冲击电压的击穿波形,统计并分析了不同冲击电压下的伏秒特性以及击穿电压概率分布。结果表明:标准操作冲击电压的击穿点集中分布在波形幅值处,少量分布在波尾;振荡操作冲击电压的击穿点分布在各振荡波峰附近,且大部分集中在第1个波峰处;对比10%、50%和90%的击穿概率电压,振荡操作冲击电压高于标准操作冲击电压;对比伏秒特性曲线,振荡操作冲击电压高于标准操作冲击电压,且当振荡频率上升,伏秒特性曲线的电压水平上移;振荡操作冲击电压的Weibull分布曲线更为平缓,随着振荡频率上升,覆盖电压范围更广,在高压区域呈"分散"现象。Switching impulse voltage may attack power transformers at a higher frequency than lighting impulse voltage.To discover the breakdown characteristics of transformer oil under oscillating switching impulse and standard switching impulse,three negative oscillating switching impulse(OSI)with oscillating frequency of 3,6 and 12 kHz and standard switching impulse(SI)are adopted to test a slightly non-uniform electric field model which has a 2.5 mm distance plate-plate electrode structure.In order to analyze breakdown characteristics,the breakdown waveforms of OSI and SI are recorded.At the same time,the volt-second characteristics and breakdown voltage probability distribution are analyzed.The results show that the breakdown points distribute mostly near the peak of wave under SI while they distribute near the peaks in several periods of wave under OSI,most near the first peak.The 10%,50% and 90% breakdown voltages under OSI are higher than those under SI.The volt-second characteristics under OSI are also higher.With the increase of oscillating frequency,the voltage level of volt-second characteristics will rise.The slope of Weibull probability curve under OSI is larger than that under SI,and with the increase of oscillating frequency,the coverage voltage range is wider and"dispersion"occurs in the high voltage region.

关 键 词：击穿特性 振荡型操作冲击电压 变压器油 稍不均匀场 伏秒特性 

分 类 号：TM41[电气工程—电器]