为准确获取变压器绕组的轴向固有模态特性,以一台10 kV变压器为研究对象,通过设计和搭建模态测试平台,得到了变压器绕组正常工况和典型故障下的轴向振动频率响应函数,综合抗差最小二乘法和多参考点最小二乘复频域法识别得到了变压器绕组的轴向固有模态参数.结果表明:加入抗差最小二乘法的识别方法可较为准确地得到不同状态下的变压器绕组模态参数;变压器绕组前4阶固有频率对应的模态振型具有较好的对称性;绕组松动和变形时,其前4阶固有频率均有所降低.研究结果可作为变压器绕组结构优化设计及机械状态在线监测的评价参数.%In order to master axial natural modal features of transformer winding, this paper takes one 10 kV transformer as research object and by designing and building a modal testing platform, it obtains response functions of axial vibration frequencies of the transformer under normal condition and typical fault condition.Meanwhile, it identifies and gets parameters of axial natural modal of transformer winding by combining the least robustness square method and PolyMAX method.Results indicate it is able to accurately get modal parameters of transformer winding under different states by introducing the least robustness square method, modal vibration patterns corresponding to first four order natural frequencies have good symmetry, and when transformer winding is loose and deformed, its first four order natural frequencies decrease without exception.The research results can be regarded as evaluation parameters for optimized design on transformer winding structure and online monitoring for mechanical state of winding.
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