A Multiphysics Computational Method for Thermal Field of Transformer Winding Using Finite Element Method

Since the age of the insulation is strongly dependent on the thermal field of transformers, accurate computation of temperature distribution, the hot-spot temperature and reducing the temperature rise are crucial concerns when designing power transformers. With the development of advanced numerical solution techniques, the complicated multiphysical fields including fluid and thermal fields inside power transformers are widely simulated. In this work, the numerical formulations for all the physical fields and the iterative schemes are summarized for computing the thermal rise of transformers. And both oil-directed and oil-natural thermal dissipation modes are simulated using in-house developed code. A parameterized mesh of the transformer is built by calling open source mesh generators for the fast design of transformers, where inlet position parameters are also optimized for illustration of the convenience by utilizing the in-house code. Numerical examples are presented to showcase the results of the in-house developed scripts based on open source software packages. The contribution of this work lies in that it provides a convenient geometric modeling and numerical computation framework for the analysis of complicated multiphysical fields within the same coding framework, instead of having to switch among different packages when using commercial finite element software. The developed in-house scripts can be used also for convenient optimal design of shape parameters of real-world transformer applications.