Güven KÖMÜRGÖZ, Nurdan GÜZELBEYOĞLU

Kendi kendine soğuyan kuru tip güç transformatörlerinde sıcaklık dağılımının belirlenmesi

Yüksek gerilim sargısı yüksekliği $537,6.10^{-3}$ m olan, 13 bobinden meydana gelmiş, dilimli, silindirik sargılı kendi kendine soğuyan kuru tip bir güç transformatöründe Ansys sonlu elemanlar programı ile sıcaklık dağılımı çıkarılmıştır. Alt, üst gerilim sargılar ve çekirdek ayrı alınarak sargılar ve çekirdek arasındaki yağ kanalının soğutma etkisi de dikkate alınmıştır. Akışkan özelliklerinin sıcaklıkla değişmesinden dolayı akışkan ve sıcaklık beraber çözülmüştür. Sargılar ve çekirdeğin sıcaklık dağılımlarının yanında bu parçaların etrafında bulunan havanın hareketi ve sıcaklığı da bulunmuştur. En çok ısınan noktanın yeri ve büyüklüğü belirlenmiştir. Yüksek gerilim sargı yüksekliği boyunca sıcaklık dağılım eğrisi çıkartılmıştır. Sıcaklık dağılım eğrisi deneysel çalışmayla elde edilen eğriyle karşılaştırılmıştır.

Determining of the temperature distribution of self-cooled dry-type power transformer

In order to find the location and the temperature level of hot spots, the temperature distribution of the transformer must be determined. The life of the transformer, the duration in which the transformer is safely over-loaded and the loading capability of the transformer can be increased greatly if the temperature of the hot spot is known. Therefore, it's crucial to determine the hot spot temperature along the windings. In this study, the temperature distribution of a dry-type power transformer with thirteen coils was determined using the ANSYS based on finite elements method. Each winding was cylindrical and disc-type. The upper voltage winding that was $537,6.10^{-3}$ m height and the core were taken into account separately. The solution was determined by taking into account the change of fluid properties with temperature. As well as the temperature distribution of the windings and the core, the temperature distribution and the movement of the surrounding air was also determined. The temperature level and the location of the hot spot were determined. The temperature distribution curve was determined along the height of the high voltage winding. The temperature distribution curve was compared with the experimental results. The results obtained are in good enough agreement with experimental results

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