Yağlı tip transformatörde termal ve yapısal analiz

Year 2024, , 84 - 93, 15.01.2024

Beyza Nur Dursun , Bulent Ekici

https://doi.org/10.28948/ngumuh.1359866

Abstract

Bu çalışmada, 1600 kVA gücünde hermetik olarak kapatılmış bir transformatör kullanılarak mekanik hesaplamalar yapılmış ve enerji iletiminden kaynaklanan ısıya göre analizleri yapılmıştır. Transformatörde oluşan ısı izolasyon yağının ısınmasına ve hacminin artmasına neden olur. Buna bağlı olarak trafo tankında artan izolasyon yağı hacmi tank üzerinde basınç artışına neden olur. Çalışmamızda sıcaklığın oluşturduğu mekanik gerilmeler ve oluşan ısıya bağlı olarak basınç artışı hesaplanmıştır. Bu hesaplamalar, oluklu duvarlı tankın mukavemet, soğutma ve yapım yaklaşımlarına göre incelenmiş ve sonlu elemanlar yöntemine dayalı ANSYS@FLUENT ve ANSYS@MECHANICAL kombinasyon simülasyon yazılımı kullanılarak tasarımdaki etkisi analiz edilmiştir. Sıcaklık dağılımı ve termal sınırlamalar doğru tasarım için kritik öneme sahiptir. İzin verilen termal sınırları aşan sıcaklıklar, transformatör bileşenlerinde ciddi hasara neden olabilir. Öte yandan sayısal, analitik ve deneysel değerlerin karşılaştırılması için test edilmiş bir prototip tank sağlanmıştır. Ancak sonuçlara göre, kritik bağlantı noktalarında gerilme yoğunlaşmaları gözleniyor, bu da ekstra beklenmedik bir yükün gerçek olması durumunda sorun olasılığını gösteriyor.

Keywords

sargı, dizayn, trafo, yapısal ve termal analiz, akış

Project Number

-

Thermal and structural analysis of oil-based type transformer

Abstract

In this paper, a hermetically sealed transformer with a power of 1600 kVA is used to make the mechanical calculations and analysed according to the heat generated by energy transmission. The heat generated on the transformer causes the insulation oil to heat up and increase in volume. Accordingly, the increasing insulation oil volume in the transformer tank causes a pressure increase on the tank. In our study, mechanical stresses created by the temperature and pressure increase due to the heat generated are calculated. These calculations are investigated according to strength, cooling, and construction approaches of tank with the corrugated wall and analysed its effect in design using ANSYS@FLUENT and ANSYS@MECHANICAL combination simulation software based on Finite Element Method. Temperature distribution and thermal limitations are critical to correct design. Temperatures exceeding the permissible thermal limits can cause serious damage to transformer components. On the other hand, a tested prototype tank is provided to compare the numerical, analytical, and experimental values. However according to the results, the stress concentrations are observed at the critical connection points, indicating the possibility of failure if an extra unexpected load is real.

Keywords

winding, design, transformer, structural ad thermal analysis, flow

Project Number

-

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