A Modal Model of Common-Mode Chokes for Conducted Interference Prediction

In this paper, a new methodology to characterize common-mode chokes is presented. It is based on a model where common-mode and differential-mode interference is separated into different ports. This methodology is used to explain modal conversion inside common-mode chokes, predict the common-mode and differential-mode conducted emissions when common-mode chokes are connected to electric devices, and improve the filtering performance of common-mode chokes by finding the optimal common-mode choke parameters.