FEM and CFD analysis of a hybrid cooling system design in oil-type transformers

Year 2022, Volume: 11 Issue: 3, 611 - 619, 18.07.2022

Murat Toren

https://doi.org/10.28948/ngumuh.1122317

Abstract

Oil-type transformers (YTT) are electrical machines with high usage in the transmission and distribution process of electrical energy. These transformers are widely used due to their low production costs and wide usage area. In the distribution system of electrical energy, approximately 80-85% of transformers consist of YTT. When these data are taken into account, the importance of the operation, performance parameters and the cooling systems that affect them come to the fore increasingly. The cooling of YTT is generally provided with naphtanic / paraffinic based oils, also called transformer oil. The use of oils for cooling purposes in YTT causes environmental pollution and requires high costs for operation, maintenance-repair activities. Today, current and interdisciplinary researches are carried out for the cooling of transformers with alternative methods. In this study, with a hybrid system, the heat generated during operation at 5kVA YTT is provided to cool the enclosure volume by using water and oil fluids at certain rates. The designed hybrid cooling system is analyzed with the finite element method (FEM) and computational fluid dynamics (CFD), and it is examined from the results that the YTT life cycle can be increased up to 5.48 - 166.6 hours.

Keywords

Oil type Transformer, FEM, CFD, Hybrid Cooling, Life Cycle

Yağlı tip transformatörlerde hibrit bir soğutma sistem tasarımının FEM ve CFD analizleri

Abstract

Yağlı tip transformatörler(YTT), elektrik enerjisinin iletim ve dağıtım sürecinde yüksek kullanıma sahip elektrik makineleridir. Bu transformatörler üretim maliyetlerinin düşük olması ve kullanım alanının geniş olması nedeniyle yaygın olarak kullanılmaktadır. Elektrik enerjisinin dağıtım sistemi içerisinde transformatörlerin yaklaşık % 80-85’i YTT den oluşmaktadır. Bu veriler dikkate alındığında yağlı tip transformatörlerin çalışmaları, performans paramet-releri ve bunları etkileyen soğutma sistemlerinin önemi de artan ölçüde ön plana çıkmaktadır. YTT’nin soğutulması genel olarak trafo yağı da denilen naftanik / parafinik bazlı yağlarla sağlanmaktadır. YTT’de soğutma amaçlı olarak yağların kullanılması, çevre kirliliğine neden olduğu gibi işletme, bakım-onarım faaliyetleri için yüksek maliyet gerektirmektedir. Günümüzde, transformatörlerin alternatif yöntemler ile soğutulması için, güncel ve disiplinler arası araştırmalar yapılmaktadır. Bu çalışmada ise 5kVA YTT’de çalışma sırasında oluşan ısının hibrit bir sistemi ile mahfaza hacminin belirli oranlarda su ve yağ akışkanları kullanılarak soğutulması sağlanmaktadır. Tasarlanan hibrit soğutma sistemi sonlu elemanlar metodu (FEM) ve hesaplamalı akışkanlar dinamiği(CFD) ile analiz edilerek sonuçlardan YTT faydalı ömrünün 5.48 – 166.6 saate kadar arttırılabileceği incelenmektedir.

Keywords

Yağlı tip Transformatör, FEM, CFD, Hibrit soğutma, Faydalı Ömür

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