LAUSR

The proposed paper unveils various sources of conducted and radiated electromagnetic interferences (EMIs) of an interleaved dc–dc converter with gallium nitride (GaN) transistors and describes different optimization strategies. Instead of striving to achieve conformity to electromagnetic compatibility (EMC) standards, it rather focuses on deriving a deeper understanding of the source of EMI phenomena related to fast switching power converters generalizing critical aspects that need to be kept in mind during the design stage. The fast switching transients of GaN transistors are the main reason for increased EMI, which is why the characteristics of the applied transistors are investigated closely, paying special attention to the parasitic switching oscillations. Various observed interference effects are presented and corresponding conclusions are drawn. The effects are divided into intra-EMI issues of capacitive and inductive near-field coupling related to signal instability and inter-EMI issues of conducted and radiated noise. Based on these findings, different optimization strategies are presented addressing signal filtering, an optimized printed circuit board design, as well as proper high-frequency designs of passive components such as capacitors for the dc link and the power choke. All findings are put into context with the EMI characteristics of an equivalent dc–dc converter utilizing Si-insulated gate bipolar transistors (IGBTs).