EMI comparison of hard switched, edge-resonant, and load resonant DC/DC converters using a common power stage

This paper compares conducted EMI of hard switched, edge-resonant, and series resonant power converters. All of the DC/DC converters use a common power stage, output filter, transformer, and gate drive electronics, with minimal modifications to support the different topologies and control approaches. The edge-resonant converter has the lowest conducted EMI emissions at light load conditions, and the lowest differential mode EMI for heavy load conditions. The paper also discusses the importance of maintaining balance and symmetry when decoupling the common mode and differential mode noise components from the LISN voltages.