Numerical approaches for conducted emissions predictions in electromagnetic compatibility

This thesis aims to investigate the modeling approaches for the prediction of the conducted emissions of electromagnetic devices, with particular focus on Switched Mode Power Supplies (SMPS), i.e. power converters based on switching semiconductor devices (MOSFETs, IGBTs). It has been established that the main source of the Electromagnetic Interference (EMI) noises is the switching activity of these components, which generate high voltage and current slew rates. Since a device that is not compliant with the regulations in terms of limits conducted emissions cannot be placed on the market, researchers have been trying to find methods for addressing Electromagnetic Compatibility (EMC) issues during the design stage to save time and additional costs. This work first explores the literature related to predicting the conducted emissions, to understand all the different modeling approaches that have been presented. Then, the focus is given to the most recent techniques for extracting equivalent circuits of the devices under test. A time domain simulation of the whole measurement setup, including equivalent circuits of the LISN (Line Impedance Stabilization Network), spectrum analyzer/EMI receiver, cable connections and parasitic couplings can be performed for the extraction of the conducted emissions spectra. The last chapter is dedicated to the study of an electronic board, which is taken as an example of device under test for the prediction of the conducted emissions.