رسائل ماجيستير
English
2021
An Experimental Study To Enhance The Cooling Performance Of Power Distribution Transformer
زيد معن, أيمن عبدالكريم عباس, حسنين غني
الكلية التقنية الهندسية - نجف-جامعة الفرات الأوسط التقنية · العراق
In the conversion process of an electrical transformer, some power is lost and converted into heat. These heat losses lead to temperature rises that have to be controlled with cooling solutions, since working with high temperatures lead to the deterioration of components and reduces the lifespan of the transformer. For this purpose, transformer's coils and core are generally immersed in an oil-filled corrugated tank. The oil is heated in this tank and then cooled in the external heat exchangers of electrical transformers. Standard radiators consist of thin vertical panels. Which transfers the heat of the oil to the air surrounding by the process of natural or forced convection. Objective of this work is to find the maximum cooling capacity and temperature variations of vertical radiator panels experimentally. Three values of oil flow rates (1, 2, and 3 ℓ/min) and three variable values for temperature(50, 60, and 70 ᵒC) were used. To cool the oilused in the transformer, two configurations are used namelyoil-direct air natural (ODAN) and oil direct air force (ODAF). This work usesa new cooling method through a utilized Metal Foam Heat Exchanger (MFHE) by exploiting its porous medium and controlling its porosity value, which was (17% and 35%), respectively. The results showed a maximum cooling capacity for both models (ODAN) and (ODAF), compared when used the new cooling method (MFHA) with two different values of porosities (17% and 35%), where the results showed that the porosity with (35%) approved is active to develop heat exchanger of a transformer. Primarily results obtained when used (MFHE) cooled with (35%) of porosity when the case is (Fans Off); the maximum cooling capacities are (782, 1580.9, and 2278.9 W) at an oil flow rate 3 ℓ/min. Secondary results that showed when used (MFHE) cooled with (35%) of porosity, at case of (Fans ON), the maximum cooling capacities (1149.8, 2017.6, and 3000 W) at oil flow rate 3 ℓ/min. The results of the experimental test showed an improvement in the oil heat transfer rate, especially after increasing the metallic foam sponges from17%, to35% for both transformer cooling methods.