Computer-aided analysis and reduction of conducted EMI in switched-mode power converter

A computer-aided analysis allows an acceptable time-and cost-effective method of achieving the required EMI performance without the need of constructing prototypes for EMI investigations. In this paper, a method for the accurate prediction of conducted EMI in switch-mode power supplies is introduced. Investigations into the source of the generated noise and its spreading path in power supplies are considered. Models of the components of power converters, such as transformers, power devices and capacitors, are modified to include functional behavior as well as EMC characteristics. The differential- and common-mode components of the conducted emission are simulated simultaneously. Simulation results are verified by experiments.