volume | PIER Journals

Abstract

During the switching transient process of high-frequency devices, such as gallium nitride and silicon carbide, an increase in switching frequency will lead to an increase in the distributed distributed leakage inductance (existing between each coil turn and each layer, as well as magnetic flux leakage) and capacitance values (existing between each turn and each layer of each winding, between different windings, and between the winding and the shielding layer). These parasitic parameters will generate sharp voltage peaks, increase power loss, and even cause surge currents and oscillations. To address these issues, this paper proposes an equivalent power-loss model based on a six-layer planar transformer. By designing interleaved coils and introducing variable impedance parameters X_{1-2; 11-14; 21-24}, d_{1-2; 11-14; 21-24}, and S_{1-2; 11-14; 21-24}, this high-frequency transformer can reduce leakage inductance while increasing excitation inductance, thereby significantly reducing the total power loss of the high-frequency transformer. The optimization design of the high-frequency transformer and the analysis of power loss are of great significance for improving the efficiency of high-frequency DC-DC power supply systems.

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Dr. Rui Zhang

Dr. Honghua Xu

Dr. Han Meng