Improved lumped-Pi circuit model for bulk current injection probes

Abstract

In this work, a lumped-parameter circuit model of injection probes for bulk current injection (BCI) is derived and discussed. The model is extracted from scattering parameter experimental measurements carried out with the probe mounted on an ad hoc calibration fixture, ideally working as an electrically-short transmission line. A circuit model of the overall calibration fixture is used to de-embed setup-related effects in order to identify the circuit structure of the probe model. The proposed model extends those developed in the past by accounting for frequency dependent inductive coupling (dispersion and losses of the ferrite), capacitive coupling between the probe and the wiring under test, and setup related effects.