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http://dx.doi.org/10.5762/KAIS.2016.17.12.511

Numerical Analysis of Resin Filling Process for a Molded Dry-type Potential Transformer  

Kim, Moosun (Metropolitan Transit Convergence Research Division, Korea Railroad Research Institute)
Jang, Dong Uk (Wireless Power Transfer System Research Team, Korea Railroad Research Institute)
Kim, Seung Mo (Korea University of Technology and Education, School of Mechanical Engineering)
Publication Information
Journal of the Korea Academia-Industrial cooperation Society / v.17, no.12, 2016 , pp. 511-517 More about this Journal
Abstract
Current oil-type potential transformers for trains are filled with insulating oil, which could have problems like explosions due to rising inner pressure during train operation. Therefore, mold and dry-type potential transformers are being developed to prevent explosions. One problem in manufacturing mold-type transformers is preventing void formation around the coiled core inside the mold during epoxy filling, which could cause an electrical spark. Micro voids can remain in the resin after filling, and macro voids can occur due to the structure shape. A transformer that is being developed has a cavity at the junction of the core and the coil for better performance, and when highly viscous epoxy flows inside the cavity channel, macro voids can form inside it. Therefore, in this study, the free-surface flow of the mold filling procedure was analyzed numerically by applying the VOF method. The results were used to understand the phenomena of void formation inside the cavity and to modify the process conditions to reduce voids.
Keywords
Dry-type transformer; Epoxy; Mold filling; VOF; Void;
Citations & Related Records
Times Cited By KSCI : 2  (Citation Analysis)
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1 I. Mihosha, Instrument transformers, Electric Book in Japan, p.126-128, 1950.
2 K.H. Cho, C.H. Jang, "The Design and Test Technology of Metering Out Fit", KIEE Summer Conference 2003, p.1803-1805, 2003.
3 T. Hasegawa, "Application Technology of Molded products in the Field", Takaoka Review, vol. 43., no. 4, p.66-72, 1996.
4 C.W.Hirt, B.D. Nichols, "Volume of Fluid (VOF) Method for the Dynamics of Free Boundaries", Journal of Computational Physics, vol. 39, pp.201-225 , 1981. DOI: https://doi.org/10.1016/0021-9991(81)90145-5   DOI
5 S.H.Shin, W.I.Lee, "Finite Element Analysis of Flow with Moving Free Surface by Volume of Fluid Method", Transactions of the Korean Society of Mechanical Engineers-B, vol. 21, no. 9, pp.1230-1243, 1997.   DOI
6 M.S.Kim, S.H.Shin, W.I.Lee, "A New VOF-based Numerical Scheme for the Simulation of Fluid Flow with Free Surface ( I ) - New Free Surface Tracking Algorithm and Its Verification-", Transactions of the Korean Society of Mechanical Engineers-B, vol. 24, no. 12, pp.1555-1569, 2000.   DOI
7 M.S.Kim, J.Park, W.I.Lee, "A New VOF-based Numerical Scheme for the Simulation of Fluid Flow with Free Surface ( II ) - Application to the Cavity Filling ad Sloshing Problems -", Transactions of the Korean Society of Mechanical Engineers-B, vol. 24, no. 12, pp.1570-1579, 2000.   DOI
8 I.Y.An, Y.L.Lee, "A Numerical Analysis Study on Two-phase Flow for the Development of High-efficiency Toilet", Journal of the Korea Academia-Industrial cooperation Society, vol. 13, no. 12, pp.5661-5668, 2012. DOI: http://dx.doi.org/10.5762/KAIS.2012.13.12.5661   DOI
9 M.S.Kim, S.M.Kim, "Filling Behavior of Polymer Melt in Micro Injection Molding for V-Grooves Pattern", Journal of the Korean Society of Manufacturing Technology Engineers, vol. 23, no. 3, pp.291-298, 2014. DOI: https://doi.org/10.7735/ksmte.2014.23.3.291   DOI