On the Implementation of a DC-DC Power Supply for Reducing Electromagnetic Interference from Power Converters and Filters

Together with mass, volume and efficiency, reduction of electromagnetic interference emission should drive the power supplies optimization criteria at the start of the design process. Although basic methods for filtering and shielding exist to reduce electromagnetic emissions below the ECSS mask margins, systematic techniques, based on symmetry, impedance matching and balancing, distributed and multi-point grounding, spread-spectrum techniques or even utilization of chaotic behaviour have the potential of reducing electromagnetic emissions beyond simply increasing the size of common and differential mode filters. This paper provides a practical comparison of six DC-DC low power converters that implement different techniques for such reduction with the overall goal of positioning the conducted emissions on the primary power bus in the frequency domain for differential and common mode currents more than 20dB below the limits in ECSS-E-ST-20-07C. The conclusions are expected to not only result in better reduction of electromagnetic interference for missions with especially sensitive payloads or scientific instruments and their demanding requirements, but also to provide mass and volume reductions for generic emission requirements.