Characterisation of the core and winding vibrations of power transformers with regulator windings

Abstract

This dissertation presents research and experimental work done to characterize the core and winding vibrations of power transformers with regulator windings by measuring the tank vibrations. The experimental tests were performed in the manufacturing plant whilst the transformers under investigation were subjected to the standard factory acceptance tests, specifically the no load loss test (open circuit test) and the full load loss test (short circuit test). The vibration measuring sensors that were used included a laser Doppler vibrometer and a tri-axial accelerometer and the vibrations were recorded with a CoCo-80 data logger. The test results show that the characteristics of the core and winding vibrations of transformers with and without regulator windings are very similar, but in the case of transformers with regulator windings, the winding vibrations have a few more dependencies. Thus this research and experimental work provide key insights into how the core and winding vibrations of power transformers with regulator windings are influenced by the regulator windings, how the tank vibrations of transformers with regulator windings should be measured and the difference between the vibrations of transformers with and without regulator windings. The importance of this is that most of the research that has been done on transformer vibrations, have been done on transformers without regulator windings, but most practical transformers do have regulator windings. Thus there is a shortage of practical transformer vibration information, which this study aims to address.