Reducing Conducted Emissions at the Output of Full-Bridge DCDC Converters with High Voltage Steps

In this work, we analyze the impact of output filter design techniques aimed to reduce conducted emissions at a DCDC power converter. A thorough analysis, based on high-frequency circuit models converter, is performed assess expected improvements offered by different strategies. This analysis then confronted with measurements 300 W 48 V 12 Phase Shift Full Bridge (PSFB) prototype. Those experimental results demonstrate that symmetric arrangement LC and direct bonding return terminal converter chassis are effective common mode output. also symmetry can in differential high frequencies, where conversion predominant contribution noise. However, may be ineffective frequencies due parasitic inductance associated connection. Main conclusions drawn for applicable general isolated converters voltage step between low sides. Since reduction studied here do not increase number components, they especially suitable applications density an important requirement, e.g., aerospace or automotive applications.