Diagnosis of Radial Deformation and Axial Displacement Faults in Power Transformer Windings using X-ray and Compton Backscatter Imaging

Abstract

Continuous and uninterrupted transmission and distribution of electrical energy is highly dependent on the flawless operation of power transformers. Failure of these critical components can lead to network power interruptions and consequently have severe detrimental consequences. Therefore, timely detection and diagnosis of power transformer faults is crucial not only to prevent the escalation of faults but also to minimize repair and maintenance costs. Conventional methods for inspecting windings faults have limitations such as the need to take the transformer out of service, unreliable results, and the addition of auxiliary devices inside the transformer, such as dielectric windows. In contrast, the proposed method in this paper utilizes a Compton Backscatter Imaging (CBI) or X-Ray Transmission (XRT) device located outside the transformer, eliminating the need for any additional equipment. This enables online scanning of any number of transformers to assess their health status and identify the type, extent, and progression of potential internal faults. Experimental results demonstrate the feasibility of the proposed method for detecting radial deformation and axial displacement and disk space variations faults of varying magnitudes and locations in both high-voltage and low-voltage windings of power transformers.