<p dir="ltr">V2: FEMM Lua scripts have been corrected for T-model (Fig. 7 in A. J. Hanson and D. J. Perreault, "Modeling the Magnetic Behavior of N-Winding Components: Approaches for Unshackling Switching Superheroes," in IEEE Power Electronics Magazine, vol. 7, no. 1, pp. 35-45, March 2020, doi:10.1109/MPEL.2019.2959356.)</p><p dir="ltr">Supplementary materials: Comparison of Three-Winding Transformer Model Extraction Using FEMM and COMSOL Multiphysics®.</p><p dir="ltr">This research focuses on simulating a transformer using electromagnetic field solver software: FEMM and COMSOL Multiphysics®. These tools are used to simulate and extract the model of a three-winding transformer. The primary objective of the extracted model is to predict key magnetic parameters, such as leakage and magnetizing inductances. These inductances play a critical role in switch-mode power converter topologies, ensuring proper operation and achieving high efficiency through zero-voltage or zero-current switching. In this study, the transformer, based on an ER28/14/11 core, is simulated using both FEMM and COMSOL, with the resulting models compared to each other and experimental measurements. FEMM is a free, 2D solver, while COMSOL is a commercial, 3D solver. This research aims to evaluate the feasibility of using the non-commercial FEMM tool to simulate complex transformer core shapes. Transformations of the E, ER, and ETD core types for simulation in both 2D axis-symmetric and planar problem types are also proposed.</p>