Model of the capacitive effects in magnetic components

A model for the capacitive effects in magnetic components for switch mode power supplies (SMPS) has been developed. It can be applied to multiwinding transformers. A finite element analysis (FEA) tool is used to compute the frequency behavior of the magnetic component, taking into account geometry and materials. The parameters of the model can be calculated before the magnetic component is built. An accurate capacitances modeling is expected to be crucial for common-mode EMI transmission modeling. The model takes into account winding floating voltages and the capacitance among each winding. Several model levels with different degrees of freedom are proposed. Some experimental results comparing the actual magnetic component results with the behavioural simulator results, are presented