摘要
研究冷轧硅钢片铁心磁性能和油纸绝缘介电性能对绕组频率响应的温度效应。推导稀疏线圈在有铁心和空心时的阻抗差异与铁心复磁导率,以及绝缘材料的阻抗与其复介电常数的频率依赖关系。在频率范围从1k Hz到1MHz对铁心复磁导率、油和纸绝缘复介电常数和模型变压器两种绕组的频率响应进行从110℃自然降温到30℃的试验研究。获得铁心复磁导率、油和纸绝缘材料复介电常数随温度变化的规律,探讨了纸占比对油纸复合绝缘介电特性的影响,讨论铁心和油纸绝缘单独作用时绕组频率响应特征的变化趋势。进而用变压器这2种材料温度特性结合绕组等效电路解释了模型变压器层式绕组和饼式绕组的频率响应随温度变化的特征,认为绕组等效(合成)电感与等效电容的乘积变化最终决定了(反)谐振频率移动方向。为了正确地解释变压器绕组频率响应,应密切关注绕组变形试验时的温度。
This paper presented temperature effects on the frequency response analysis(FRA) characteristics of a winding considering two aspects.The first aspect was the magnetic properties of a core made of cold rolled silicon steel laminations,and the second aspect was the dielectric properties of oil-paper insulation.The frequency-dependent relation of the impedance difference of a sparse coil,with and without an iron core,to the core complex permeability was derived.Similarly,the relation between the impedance of an insulating material and its complex dielectric permittivity was also derived.The complex permeability of the silicon steel,the complex permittivity of the mineral oil and insulating paper,and the FRA characteristics of two model transformer windings were experimentally studied in the frequency range of 1 kHz to 1 MHz,as the temperature decreases naturally from 110℃ to 30℃.The change regularity of the complex permeability of the iron core and the complex permittivity of the oil and paper insulation with temperature were obtained.The influence of the ratio of the insulating paper to the whole oil-paper compound insulation in thickness on its dielectric properties was explored.The change tendency of the FRA characteristics of a winding was discussed when its iron core or oil-paper insulation acted alone.Furthermore,the change of the FRA signatures of the two windings with temperature was explained by combining the temperature characteristics of the two transformer materials and the winding equivalent circuit.The shift of oscillation frequency in the FRA curve of a winding was finally determined by the product of its equivalent(synthesized) inductance and capacitor.
作者
王国利
牛成林
王璐
李洋
叶建区
王婷婷
罗勇芬
何立柱
WANG Guoli;NIU Chenglin;WANG Lu;LI Yang;YE Jianqu;WANG Tingting;LUO Yongfen;HE Lizhu(State Key Laboratory of HVDC(Electric Power Research Institute,CSG),Guangzhou 510663,Guangdong Province,China;State Grid Tongchuan Power Supply Company,Tongchuan 727031,Shaanxi Province,China;School of Electrical Engineering,Xi’an Jiaotong University,Xi’an 710049,Shaanxi Province,China)
出处
《中国电机工程学报》
EI
CSCD
北大核心
2020年第3期999-1008,共10页
Proceedings of the CSEE
基金
特高压工程技术(昆明、广州)国家工程实验室开放基金(NEL201811)~~
关键词
温度
绕组
频率响应分析
复磁导率
复介电常数
temperature
winding
frequency response analysis(FRA)
complex permeability
complex permittivity
