电力变压器绕组变形状态下的振动信号特性分析  

Vibration signal characteristic analysis of power transformer winding under deformation state

作　　者：邓旭东 张占龙[2] 夏远灿 汪力 吴琛 房劲 王凡 DENG Xudong;ZHANG Zhanlong;XIA Yuancan;WANG Li;WU Chen;FANG Jin;WANG Fan(Ultra-High Voltage Branch of State Grid Chongqing Electric Power Company,Chongqing 400039,China;State Key Laboratory of Power Transmission Equipment Technology(Chongqing University),Chongqing 400044,China;State Grid Chongqing Electric Power Company Wushan Power Supply Branch,Chongqing 404700,China)

机构地区：[1]国网重庆市电力公司超高压分公司,重庆400039 [2]输变电装备技术全国重点实验室(重庆大学),重庆400044 [3]国网重庆市电力公司巫山供电分公司,重庆404700

出　　处：《电工电能新技术》2024年第10期13-23,共11页Advanced Technology of Electrical Engineering and Energy

基　　金：国网重庆市电力公司科技项目(2024渝电科技52#)。

摘　　要：近些年来国内电力变压器绕组机械故障频发,利用振动法监测电力变压器机械运行状态可以有效规避变压器故障风险。本文首先基于电力变压器绕组振动来源和加速度理论求解分析,搭建了110 kV电力变压器有限元模型,研究了变压器绕组在额定正常负载工况下的振动规律,发现了变压器在负载工况下绕组辐向振动强度远大于轴向振动,且绕组振动信号主频为100 Hz;在绕组上下端部固定约束条件下,其上下端振动强度小于绕组中间部位。然后,改变高压绕组几何形状使其发生鼓包变形,通过对比分析绕组未变形状态下的振动信号得出:当绕组发生形变时,其振动信号频谱中出现大量高次倍频谐波分量;随着绕组形变程度的加深,其振动信号主频不断增大,高次谐波分量分布也更为复杂。最后,通过定义基频占比、高频占比这两个特征参量,进一步分析了变压器绕组形变前后的振动特征变化规律,为实际现场利用振动法评估变压器绕组机械状态提供了依据。In recent years,mechanical failures in domestic power transformer windings have been frequent.Utilizing vibration analysis to monitor the mechanical operation of power transformer windings can effectively mitigate the risk of transformer failures.This article first analyzes and solves the vibration sources and acceleration theory of power transformer windings,establishes a finite element model of a 110 kV power transformer,studies the vibration characteristics of the transformer windings under rated normal load conditions,and finds that the radial vibration intensity of the windings under load conditions is much greater than the axial vibration,with a main frequency of 100 Hz in the winding vibration signal.With fixed constraints at the upper and lower ends of the windings,the vibration intensity at the upper and lower ends is less than that in the middle of the windings.Next,by altering the geometric shape of the high-voltage windings to cause buckling deformation,a comparison analysis of the vibration signals in the undeformed state of the windings reveals that when deformation occurs,the vibration signal spectrum shows a significant amount of high-order harmonic components.As the degree of deformation of the windings increases,the main frequency of the vibration signal continuously increases,and the distribution of high-order harmonic components becomes more complex.Finally,by defining characteristic parameters such as the fundamental frequency ratio and high-frequency ratio,the article further analyzes the changes in vibration characteristics before and after the deformation of the transformer windings,providing a basis for evaluating the mechanical state of transformer windings using vibration analysis in actual field conditions.

关 键 词：变压器 有限元仿真 绕组变形 振动信号 频谱分析 

分 类 号：TM41[电气工程—电器]