Comprehensive Analysis of Filter Inductor Topology on Common-Mode Conducted Emissions for the Boost Converter

Recent developments in semiconductor technology and power packaging have enabled converter implementations with increased efficiency and power-density. However, the increased switching performance that makes these gains possible is also in part responsible for elevating conducted emissions signatures. A vast body of literature is dedicated to the modeling and mitigation of conducted emissions, and specifically to the suppression of common-mode (CM) noise. The authors of the present article previously developed a systematic method to isolate CM behavior of an arbitrary system through the decomposition of the mixed-mode system description into CM equivalent model (CEM). In the current study, this approach is applied to the boost converter topology. The accompanying analysis identifies the elements of greatest importance to the CM behavior of this topology, and provides new insight into the influence of the filter inductor configuration on the conducted emissions profile of this system. The developed CEM is validated through a set of empirical studies that also corroborate the emissions trends predicted by the CEM. The study concludes by introducing a procedure for suppressing conducted emissions by utilizing the CEM to design a filter configuration that maximizes CM behavior cancellation while minimizing the need for additional components.