Impedance characterastic of new type measurement system for measuring conducted disturbance

Abstract

A new structure conducted disturbance measurement system is designed and prototyped in order to improve the impedance characteristic of the previously proposed measurement system. This new-type measurement system adopts a designed equipment under test (EuT) connection which is used to propagate conducted disturbance and connect the AC plug of the EUT and the measurement system. The EUT connection is designed in a compact chassis with two plugs which are completely symmetric with the AC plug of the EUT to improve characteristic degradation due to unbalance of the EUT connection and the influence of the unwanted resonance mode in the EUT connection. This new-type measurement system shows less impedance variations in the frequency range of 10 MHz–1000 MHz. We also found that the impedance characteristic of our proposed measurement system is hardly affected by fluctuations in the actual mains impedance.