Integration of High Leakage Inductance Transformers Utilizing Genetically Optimized Curved Foil Windings


David Bündgen, André Thönnessen, Rik W. De Doncker, 2023 11th International Conference on Power Electronics and ECCA Asia (ICPE 2023 - ECCE Asia), 22 May 2023 - 25 May 2023.



In this paper, a transformer design with a magnetic shunt is proposed to achieve an efficient transformer with a precisely defined stray inductance. Highly compact transformer with a precise stray inductance are needed in highly compact dual-active-bridge and resonant converter topologies. To avoid additional eddy currents induced by the inserted shunt, 3D printed bobbins are utilized to shape the stray flux and consequently omit additional eddy currents in the windings. The transformer is simulated with a FEM-Tool and additional loss calculations. The simulation results are used as input parameters for a genetic optimizer to find suitable core and copper geometries. A design is selected from the optimization and a prototype of the transformer is realized. Finally, measurement results are presented to verify the simulations. In comparison to a non-optimized design, the optimized copper windings can reduce the AC-short-circuit resistance by 5.92 %.