Transformer impedance balanced circuit for power converters

Abstract

Impedance balancing of isolated converters to reduce common mode (CM) electromagnetic interference (EMI) noise over a wide frequency range. An impedance balanced isolator converter circuit comprises a plurality of resistor, inductor, and capacitor (RLC) branches (i) that are representative of a transformer circuit component, (ii) that are coupled in series with a plurality of respective noise source voltages, and (iii) comprise RLC parameters that are based on respective ones of a plurality of impedances associated with the transformer circuit component; a load impedance branch (i) that is representative of one or more transformer primary side circuit components and (ii) that is coupled in parallel with the plurality of RLC branches and the plurality of respective noise source voltages; and an RLC balance branch coupled in parallel with a first resistor, a first inductor, and a first capacitor that are associated with a first of the plurality of RLC branches.