基于振动的变压器铁芯松动判定方法  

Determine Method for Transformer Core Looseness Based on Vibration

作　　者：马宏忠[1] 赵宏飞[1] 陈楷[2] 王春宁[2] 吴益明[3] 黄朝志[1] 

机构地区：[1]河海大学能源与电气学院,江苏省南京市211100 [2]江苏省电力公司南京供电公司,江苏省南京市210008 [3]江苏省电力科学研究院,江苏省南京市210036

出　　处：《电力系统自动化》2013年第14期101-106,共6页Automation of Electric Power Systems

基　　金：国家电网公司重大科技项目(2011-0810-2251)~~

摘　　要：为分析和判断电力变压器铁芯松动故障,对变压器油箱表面的振动信号进行研究,提出基于油箱表面振动信号的变压器铁芯松动故障诊断方法。首先,对变压器铁芯的振动特性进行分析,并确定振动信号中100Hz为铁芯松动特征频率。为避免变压器固有振动频率的影响,对油箱壁的共振原理进行了研究,提出了先用激振法确定变压器油箱表面的固有频率,避开固有振动频率对故障诊断的影响;提出了利用100Hz特征频率分量占总分量(1kHz以内)的比值来判断铁芯松动故障的方法。变压器铁芯松动后,利用比例阈值法纵向比较(与历史数据比较)各测点的振动信号,可确定变压器是否存在铁芯松动故障;通过各测点横向比较,可初步进行变压器铁芯松动故障定位。该方法简单有效,不需要考虑电压变化以及传感器型号不同对故障判断的影响。In order to analyze and judge the power transformer core looseness fault, the vibration signal of transformer tank surface is studied. A fault diagnosis method for core looseness is proposed based on the transformer tank surface vibration signal. Firstly, the vibration characteristics of the transformer core are analyzed and 100 Hz is taken as the characteristic frequency in the core looseness vibration signal. In order to avoid the influence of the natural frequency of the transformer, tank wall resonance principle is studied. The natural frequency of the transformer tank surface is determined by using excitation method so as to avoid the impact of the natural vibration frequency on fault diagnosis. Finally, a method with the ratio between 100 Hz characteristic frequency component and the total component （within 1 kHz） to determine the core looseness is proposed. When transformer core looses, comparing the vibration signal of each measuring point longitudinally （compared with the historical data） with proportional threshold method can determine whether the transformer core has looseness fault. And comparing the measuring point horizontally can preliminary determine the transformer core loosening fault location. The method is simple and effective, and do not have to consider the change of voltage as well as the type difference of sensor to the fault judgment.

关 键 词：油浸式变压器 铁芯松动 振动 油箱壁共振 比例阈值 故障诊断 

分 类 号：TM407[电气工程—电器]