Fault discrimination of power transformers using vibration signal analysis

摘要

In power transformer, vibration signals can occur at winding and core due to the change of current, voltage, and temperature or the deformation of winding and core. The deformation of winding and core can be generated by electromagnetic force induced by fault current in power systems. Also, the changes of vibration signals can be varied in power transformers. In fact, the trends of fundamental waves and higher harmonics of vibration signals are very different in normal or fault states of power transformers. We detect and analyze the changes of vibration signals and use them as a tool for fault diagnosis of power transformers. This apper presents fault discriminating possibility by using the changes of fundametntal waves and highe harmonics in power transformers. We derived the fault discriminating functions that are made at each case; normal state and fault state in power transformers. These functions are tested by the detected vibration signals, and we showed that the proposed methods can discriminate the state of power transformers.