An Accurate and Efficient Approach for High-Frequency Transformer Parameter Extraction

Accurate parasitic parameter extraction of high-frequency transformers is one of the key techniques to efficiently design a Switched-mode power supply(SMPS). An approach to accurately and efficiently extract the parasitic parameters of high-frequency transformers is proposed. The high-frequency transformer is first decomposed into first-order RL and second-order RLC circuits according to inherent step response characteristics. Through the measured discharging pulse and damped oscillation responses of the high-frequency transformer excited by a square wave, we can extract the equivalent circuit parameters through fitting the responses with Particle swarm optimization(PSO). The equivalent circuits of the high-frequency transformer with the desired parameters are obtained for the SMPS design. We validate the effectiveness and accuracy of the proposed method with simulations and measurements.