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.