Research on Transformer Temperature Rise Based on Electromagnetic Thermal Flow Multi physical Field Coupling Analysis

Usually, the conductivity of transformer windings increases with increasing temperature, so ignoring the variation of winding conductivity with temperature can lead to underestimated winding temperature rise. In response to this phenomenon, this article establishes a three-dimensional electromagnetic thermal flow coupling numerical model for oil immersed transformers, taking into account the influence of winding conductivity changes with temperature, and thus calculating the temperature distribution of the windings. The simulation calculation results show that without considering the process of transformer winding conductivity changing with temperature, the calculation error of winding temperature rise reaches 18.02%, thus verifying the necessity and rationality of the analysis method of the electromagnetic thermal flow coupling numerical model of oil immersed transformers considering the process of winding conductivity changing with temperature, which can provide reference for the temperature rise calculation of oil immersed transformers.