Measurement of Short-Circuit Effects on Transformer Winding with SFRA Method and Impact Test

Abstract

The paper presents theoretical and experimental analyses of a possible effect of the short-circuit forces on the transformer winding. The first part of the paper is focused on creation and activity of the radial and axial forces during a short circuit. It shows dimensions, direction and − of course − the resulting mechanical stress. The presented equation shows basic dependencies of these mechanical forces created in the transformer winding. Finally, the paper presents experimental methods of diagnosing and analysing the effects of short-circuit forces on the transformer winding.

Interpretation of sweep frequency response analysis traces on inter-turn short circuit fault

“…Dominant frequency range of SFRA due to short circuit fault from bibliography survey References Dominant frequency range (Hz) [11] Devadiga et al 2018Low and medium frequency (Significant reduction in impedance and a shift in resonance peaks towards high frequencies)[12] M.Gutten, Richard Janura, Milan Sebok, DanielKorenciak, 2016 Low to medium frequencies (up to 100kHz)[13] Aljohani & Abu-Siada, 2015High levels of SC have a visible impact along the entire frequency range and influence the resonance frequencies in high frequency range.…”

Possibilities for Experimental Testing of Alarm Transmission Systems

“…From the above and using Table 1 Performance of the alarm transmission system, one of the main indicators of system reliability, is influenced by several indicators aimed at the signal transmission. Those indicators could include, for example, message transmission time, connection/connection monitoring, monitoring of the individual parts of the alarm transmission system functioning [4].…”

High-Frequency Modeling of a Three-Winding Power Transformer Using Sweep Frequency Response Analysis

“…In [7], the authors used driving-point impedance for transformer parameter estimation. In [5,[12][13][14][16][17][18][19][20], SFRA data was used to detect the deformation or fault of a power transformer. The core diagnosis based on SFRA was covered in [5].…”

“…In [12], the authors first observed the relationships between parameters and frequency response and then analyzed frequency response in fault conditions. In [13,14,17,19], the SFRA was used to diagnose interturn faults such as short-circuit faults and winding deformation. The authors of [21] presented a comprehensive, detailed review of the transformer FRA, including test methods, objectives, structures, and results.…”

“…The authors of [21] presented a comprehensive, detailed review of the transformer FRA, including test methods, objectives, structures, and results. In [5,7,9,10,14,[17][18][19][20], methods that calculate magnetic deformation using structural or physical analysis were presented with the comparison of normal and fault states via graphs.…”