94 / 2021-03-30 12:08:22

Vibration Phase Information based Real-time Fault Detection Method for Power Transformers

Fault Diagnosis,Transformer Winding,Vibration,Phase

Winding is regarded as the most failure-prone component in a transformer. According to the statistics, 70% of the total numbers of transformer winding failures are due to mechanical faults. It allows the application of the vibration analysis method in fault diagnosis of the internal components in a transformer, via observation of the transformer tank vibration. This paper shows that the tank vibration phase could provide “fault-related” information for winding fault diagnosis. Variation of vibration phases can be used as an indicator of variance in a transformer’s physical characteristics. A technique based on the transformer vibration phase is developed to evaluate the condition of windings. A set of tests are conducted on a three-phase power transformer to investigate the performance of the proposed method under abnormal operating conditions. The results are then analyzed by comparing the variations of vibration phases with and without faults. When the transformer winding is operating in a healthy condition, the vibration phase almost keeps unchanged with the current. Once a fault is introduced into the winding, the vibration phase alters dramatically with loads. The experiment results have proved that the proposed method based on transformer vibration phase can provide a sensitive and accurate measure of the winding faults.