Symmetrical-Component Approach for Circuit Modeling of EMI Emissions in Three-Phase Inverters

This paper provides the circuit model of a three-phase inverter as a four-port network. Such model is used to derive equivalent circuits for differential and common mode noise emissions when parasitic capacitances are taken into account. Moreover, a rigorous methodology based on the symmetrical component transformation is proposed to investigate the interaction between the three-phase side and the single-phase side. This allows a proper understanding of interaction between differential and common mode noise. Furthermore, the relationship between the DC side differential mode noise and the three-phase load is made clear. A more complete and rigorous circuit representation is obtained with respect to the conventional behavioral modeling available in the relevant literature.