Investigation of impact of magnetic shunt parameters on temperature distribution in transformer tanks

Abstract

A set of reduced order models are developed to validate finite element based calculation of temperature distribution in solid and laminated magnetic structures in transformers with high current carrying conductors. Model details, measured and calculated losses and temperature of the models are presented. Effect of magnetic shunt type and its alignment with respect to stray flux direction on temperature distribution in the reduced order model are analyzed. The magneto-thermal coupled field analysis methodology is applied to estimate the temperature distribution in Multi-Utility transformer, showed temperature higher than expected. Different cases of tank cover plate with electromagnetic shield , thicker magnetic shunts, and with non magnetic cover plate are analyzed to reduce the temperature. With the modified shunt arrangement, the transformer passed the test as temperature were reduced by 100˚C.