Modeling and Prediction of Radiated Electromagnetic Interference for DC-DC Power Converter

This paper develops modeling technique of the radiated electromagnetic interference (EMI) in DC-DC power converters with power cables. Firstly, an equivalent two terminal model based on Thevenin's and Norton's theorem is proposed to reveal the generation of the common mode (CM) current. Then, the antenna models are also developed, where the interaction between the noise source and the undesired antenna in the power converter's CM path is explored in detail. The spectrum of CM currents is extracted for power converter and the developed models are used to predict the radiated EMI from power converter with attached power cable. Experiments are conducted to validate the spectrum of CM current, and the predicted radiated emissions for power converter agree well with the experimental results.