Analysis of EMI Terminal Modeling of Switched Power Converters

A generalized terminal modeling technique was proposed earlier to predict conducted electromagnetic interference from a dc-dc boost converter. The predictions of these conducted emissions showed that there was a good agreement up to 50 MHz. This paper extends the generalized terminal modeling approach to converters with the buck-type input. Both dc and ac applications are discussed. The technique is developed for the electromagnetic interference modeling of switched power converters in aerospace applications where the requirements on electromagnetic pollution are very strict. The model is shown to successfully predict conducted emissions for a buck converter and a three-phase voltage source inverter up to 100 MHz with an error of 6 dB or less at most frequencies.