Electromechanical Forces in Transformers Caused by Inrush Currents: An Analytical, Numerical and Experimental Approach

  • R. Guimarães
  • A. C. Delaiba
  • J. C. Oliveira
  • E. Saraiva
  • A. J. J. Pereira Rosentino
Article
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Abstract

Within the extensive range of reasons that cause internal faults in transformers, the axial and radial electromechanical forces produced by the inrush currents show themselves as noteworthy. In fact, such events may result in high levels of transient current, which may last for quite significant periods of time. Due to this effect, there exist a number of phenomena likely to manifest themselves. One such effect consists of the occurrence of electromechanical forces and their corresponding influences on the mechanical structure and lifetime of the equipment. In this sense, this article has as its objective the analysis of the electromechanical forces in transformers, through an analytical, numerical, and experimental approach. In order to examine and identify the qualitative and quantitative nature of the phenomenon, the studies are further corroborated through the use of the modeling technique using the averages of the finite element method in its 3D version. Finally, comparative analyses are made between the analytical and computational results with those derived from experimental tests, which showed the potential of the presented studies for the purpose of subsidizing projects and providing the design of the supporting mechanical structures of the transformer windings.

Keywords

Inrush current Three-phase transformer Radial forces Axial forces Finite elements method 
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Notes

Acknowledgments

The authors gratefully appreciate the financial support given to the strategic project P&D from ANEEL: “Electromechanical Stress in Transformers Caused by High Inrush Currents and Short-Circuits” with financial support from Chesf—Companhia Hidroelétrica do São Francisco—Recife- PE.

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Copyright information

© Brazilian Society for Automatics--SBA 2013

Authors and Affiliations

  • R. Guimarães
    • 1
  • A. C. Delaiba
    • 1
  • J. C. Oliveira
    • 1
  • E. Saraiva
    • 1
  • A. J. J. Pereira Rosentino
    • 1
  1. 1.Faculdade de Engenharia Elétrica (FEELT)Universidade Federal de Uberlândia (UFU)UberlândiaBrazil

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