EMI generation models for switched mode power supplies

Electromagnetic Compatibility (EMC) between the supply systems and the control and communications systems of a satellite is one of the key points to be checked when a supply system for such equipment is designed. Up to now, there is not much literature, neither simulation tools to predict the generation of disturbances in the power supply and its propagation through the whole system. This paper describes some modelling techniques concerning the source, which allow the prediction of EMI generated in SMPS with some topologies usually employed in space supply systems. Concerning the propagation, the differential mode (DM) EMI produced by DC bus inductance and common mode (CM) capacitive coupling have been identified as the most significant mechanisms and a method for measuring both is proposed.