油隙对变压器油纸绝缘频率响应特性的影响规律

Influence of Oil Gap on Frequency Response Characteristics of Oil/Paper Insulation

频率响应法是一种评估变压器油纸绝缘状态和水分含量的方法,为研究油隙对油纸绝缘频率响应的影响规律,使用频率响应法对油纸绝缘进行建模,搭建油纸绝缘频率响应实验平台,对不同油隙大小的油纸绝缘系统频率响应进行测试和计算。结果表明:油纸绝缘系统的频率特性可以由油隙和油浸纸的频率特性进行叠加得到。油隙的大小对油纸绝缘系统频率响应测试结果尤其是低频部分的影响较大,而频率响应的低频部分对油纸绝缘状态和微水含量十分敏感,因此油隙大小是影响油纸绝缘频率响应特性的一个不可忽略的因子。

Frequency response method is a method to assess the condition and moisture content of oil-paper insulation for transformer. To study the effect of oil gap on the frequency response of oil-paper insulation, we established an oil-paper insulation model using frequency response method and built an experimental platform. The frequency response of oil-paper insulation with various sizes of oil gap were tested and calculated. The results show that the frequency characteristics of the oil-paper insulation can be obtained by superimposing the frequency characteristics of the oil gap and oil-impregnated paper. The influence of the size of oil gap on the frequency response test results, especially the low frequency parts, is remarkable. The low frequency parts of frequency response is very sensitive to the condition and moisture content of oil-paper insulation, therefore the size of oil gap is not a negligible factor influencing the frequency response characteristics of oil-paper insulation.