变压器油纸绝缘微水扩散暂态的电介质频率响应  

Dielectric Frequency Response of Oil-paper Composite Insulation With Transient Moisture Equilibrium

作　　者：刘君[1] 吴广宁[1] 周利军[1] 罗杨[1] 黄晓峰[1] 

机构地区：[1]西南交通大学电气工程学院,四川省成都市610031

出　　处：《中国电机工程学报》2013年第1期171-178,共8页Proceedings of the CSEE

基　　金：国家自然科学基金(51177136;51107105/E0705);西南交通大学博士研究生创新基金(2011)~~

摘　　要：为将电介质频率响应更准确地应用于工程实际,开展变压器油纸绝缘微水扩散暂态的电介质频率响应研究。根据电介质频率响应原理,建立测试系统,测试微水分布平衡时油纸绝缘电介质频率响应;推导介电常数及电导率不均匀分布的油纸绝缘介电模型,根据微水分布平衡稳态时的测试结果,对微水扩散暂态的绝缘频率响应进行数值计算;测试油纸绝缘微水扩散暂态的电介质频率响应,对数值计算结果进行验证。结果表明,微水分布不平衡,引入了微水浓差极化,油纸绝缘的电介质响应变化较大;随着微水浓度梯度的增大,低频段的弛豫特征更明显,弛豫中心频率向高频方向移动,低频段介质损耗减小更为明显。The research on dielectric frequency response of oil-paper composite insulation with transient moisture equilibrium was carried out in order to apply dielectric frequency response to diagnose the equipment in operating condition more accurate thereof. According to the dielectric frequency response principle, the test system was established. The dielectric frequency responses of oil-paper insulation with different moisture contents, which had been get equilibrium, were measured. A theoretical model for dielectric medium with an arbitrary distribution of conductivity and dielectric constant was proposed. The dielectric frequency response of oil-paper composite insulation with transient moisture equilibrium was simulated according the steady state dielectric frequency responses. Also, the dielectric frequency responses of oil-paper composite insulation with transient moisture equilibrium were measured to verify the numerical calculation. The results show that the dielectric frequency response of oil-paper composite insulation with transient moisture equilibrium is obvious different with the steady state one. The main reason is that the transient moisture equilibrium causes the concentration polarization. With the moisture concentration gradient increases, the low-frequency relaxation enhances and the relaxation center frequency moves to higher frequency. The dielectric loss in low frequency segment is reduced too.

关 键 词：频率响应 油纸绝缘 微水 暂态 复介电常数 

分 类 号：TM85[电气工程—高电压与绝缘技术]