Thermal Performance Analysis of the 3-φ Distribution Transformer Radiator with and without Fin Arrangement

Abstract

Transformer plays a significant role in providing a reliable and useful electricity supply. It is one of the most critical equipment in electric power transmission and distribution systems. Transformer losses are occurred by the current passing through resistance on the winding conductors. These losses are converted to heat energy. The majority of high voltage transformers are filled with liquids that work as an electrical insulation as well as a heat transfer medium. The most commonly used liquid in power transformers is mineral oil due to its low cost and good properties. The winding temperature must be kept within a limit so that the temperature dependent properties of the mineral oil do not hamper the performance of the transformer. Therefore, an air cooled radiator is generally fixed with the transformer to maintain the temperature of the mineral oil to its tolerable limit. In this study, heat transfer enhancement is investigated for different types of radiator filled with mineral oil. The thermal performance of conventional radiator and modified radiator with and without fin arrangement are analyzed through simulation and experimental results. A 200 kVA, 11 kV Oil Natural Air Natural (ONAN) cooled 3-φ distribution transformer is used for experiment. The simulation is performed using Solid Works 3D CAD Design and ANSYS 2016 version Software. A critical analysis is done with the experimental results for the transformer radiator with and without fin arrangement. The thermal performance of the radiator of 14 oval pipes with fin arrangement increases 3.45% as compared to the radiator of 14 oval pipes without fin arrangement. The cost of the radiator of 14 oval pipes with fin arrangement reduces 20.89% as compared to the conventional radiator without fin arrangement. The results obtained through simulation and experiment play vital role in the economical design of transformer radiator so that fabrication of transformer is cost effective.