Diagnosing winding and core condition of power transformer by vibration signal analysis

The ability to diagnose the integrity of the transformer windings and core through online diagnostic method would be useful for electric utilities who are concerned about the availability and reliability of power transformer. This paper presents results of a study to identify the condition of power transformer windings and core by measuring the vibration signal of outdoor transformer in normal operating conditions. The obtained vibration signal which is recorded from various places on the transformer tank is analyzed by matching the signal frequency spectrum with transformer load. From this study, mechanical integrity of windings and core inside the transformer is determined by comparing the correlation between each main frequency of vibration signal and the load among similar transformer.