运行中电力变压器油箱表面振动特性的研究

Study on the oil tank surface vibration characteristics for the running power transformer

电力变压器油箱表面的振动信号与变压器绕组及铁心的压紧状况、位移及变形状态密切相关。因此,振动信号分析法是监测电力变压器绕组和铁心状况的有效方法之一。本文利用组建起的变压器振动测量系统,对现场正在运行中的电力变压器油箱表面的振动信号进行了测量,分析了变压器型号、传感器安装位置对所测得的振动信号的影响,结果表明:同型号变压器油箱表面的振动特性相似;油箱表面上下对称位置处的振动特性相差不大,而其它各个位置处的振动信号都没有可比性。最后,本文研究了传感器的安装位置略有变化时,所测得的振动信号的变化情况,提出了应对传感器安装位置进行标记,在进行下次测量时,传感器安装位置最好在标记点处或偏离不超过5cm。本文的研究成果对于振动信号分析法的实际应用具有一定的指导意义。

Steady-state vibration recorded on the tank surface under on-line conditions provides essential information about fixation conditions both for windings and the magnetic core. Therefore, vibration signal analysis method is one of effective methods to monitor the condition of transformer windings and core. In this paper, the transformer vibration measurement system is set up and the vibration signals on the oil tank surface of running transformer in the field are measured. The influences of transformer type and sensor locations to the measured vibration signals are analyzed. The results show that, the vibration characteristics of the same type transformers are similar, and the vibration characteristics at the symmetrical positions on the upside and underside tank surface have little difference. Moreover, the vibration signals measured at other positions have no comparability. Finally, in this paper, the study about the change of vibration signal is carried on when the installed position of sensor is moved a little. It is presented that the installing position of sensor should be marked, and then if the next measurement is taken on, the installing position of sensor should be at the marked point or not exceed 5cm. The results presented in this paper can guide the application of vibration signal analysis method.