Impact of axial displacement on power transformer FRA signature

Abstract

Abstract-Frequency response analysis (FRA) is gaining global popularity in detecting power transformer winding movement and core deformation due to the development of FRA test equipment. However, because FRA relies on graphical analysis, interpretation of its signatures is still a very specialized area that calls for skillful personnel to detect the sort and likely place of the fault as so far, there is no reliable standard code for FRA signature classification and quantification. This paper investigates the impact of transformer winding axial displacement on its FRA signature as a step toward the establishment of reliable codes for FRA interpretation. In this context a detailed model for a single-phase transformer is simulated using 3D finite element analysis to emulate a close to real transformer. The impact of axial displacement on the electrical distributed parameters model that are calculated based on the transformer physical dimension is examined to investigate how model's parameters including inductance and capacitance matrices change when axial displacement takes place within a power transformer.

New statistical approach to interpret power transformer frequency response analysis: non‐parametric statistical methods

“…One of the most reliable and sensitive tools for monitoring physical condition of power transformers is frequency response analysis (FRA). FRA can efficiently detect deformation of the transformer core [1,2], deformation and displacement of the windings [3], faulty core grounds [4], collapse of partial winding [5], broken or loosen clamp connections [5], short circuited turns [6] and so on.…”

Diagnosis and clustering of power transformer winding fault types by cross‐correlation and clustering analysis of FRA results

“…The frequency response is considered as a fingerprint of the transformer which can be compared with previous marks in order to detect any kind of fingerprint change; therefore electrical and mechanical faults are detected. The FRA methods can detect short circuit turn [19,22], transformer core defects [23,24], winding deformation and displacement [14,20,21,25], loosen or broken clamp connections [26] etc., effectively.…”

Determination and localisation of turn‐to‐turn fault in transformer winding using frequency response analysis

“…FRA can detect problems in transformers such as winding deformation (axial and radial) like hoop buckling, tilting, shorted or open turns, faulty grounding of core or screens, core movement, broken clamping structures, among others [2][3][4][5][6]. FRA is used to obtain the initial signature of a healthy transformer for future comparisons.…”