Simulation of Stray and Core Shielding Loss for Power Transformer Based on 2D/3D FEM

Abstract

In recent years, the capacity has increased and the volume has been limited in the power transformers. The stray losses of the tanks and structural parts cannot be ignored in the load loss. The tanks and the structural parts are complex structures. It is difficult for transformer manufacturers to use analytical methods to calculate stray losses for each component in the power transformers. If the stray loss distribution of the components can be estimated, it will help to optimize the power transformer’s cost and performance. Therefore, this paper uses the finite element method to solve the stray loss of components in the time-varying magnetic field. At the same time, the core losses of the magnetic shielding are solved. In addition, the position of the tap is considered, and the proposed stray loss model has the temperature factor, which can improve the accuracy of the simulation results. Finally, the short circuit test experiment is carried out in the 350 MVA three-phase five-limb power transformer. The proposed models and material parameters are verified by the experimental results.

Keywords

• Finite element analysis
• power transformer
• stray loss
• impedance boundary