Verification of the Voltage/Current Conversion Factor of Transformer-Type-AAN for Conducted Emissions on Unscreened Balanced Pairs

According to CISPR 32, the voltage limits of conducted emissions on wired network ports are equal to the current limits multiplied by the common mode impedance $150\ \Omega$, which is the sum of the impedances of the asymmetric artificial network (AAN), receiver, and equipment under test (EUT). However, the voltage/current conversion factor of AANs varies depending on the common mode impedance of the EUT. This paper shows the experimental results of how the voltage/current conversion factor of transformer-type-AANs varies in proportion to the common mode impedance of the EUT, and that, while current transformer-type-AANs are affected by this phenomenon, improved transformer-type-AANs are not.