Investigation of Simultaneous Asymmetrical Axial Displacement and Radial Displacement of Transformer Windings by FRA Method

Frequency response analysis (FRA) is one of the most reliable and useful methods for mechanical fault detection in transformers. The winding axial and radial displacement is one of the mechanical fault types that can occur in transformers. Winding displacements cause the detailed model parameters changing, in response to which FRA characteristics will also change. Numerous researchers have considered winding axial displacements as a symmetrical movement of disks. However, one of the most prevalent types of winding axial displacements is asymmetrical axial displacement which has not been considered by any prior studies. In this paper, physical asymmetrical axial displacements of the first disk of the LV winding and radial displacement of the LV winding were simulated and FRA characteristics were obtained for these cases. Finally, experimental tests were performed on an experimental transformer to validate the simulation results.

Investigation of Simultaneous Asymmetrical Axial Displacement and Radial Displacement of Transformer Windings by FRA Method Keywords:

FRA , Fault , Displacement , Axial , Radial , Transformer , Asymmetrical