Effect of current probe location on response law of shielded multi-core wire

Abstract Bulk current injection (BCI) is a commonly used method in electromagnetic compatibility testing. In order to enhance the injection efficiency of the current probe, the interference process into the internal core wire is analyzed. Theoretical calculations indicate that the shielded multi-core wire exhibits a frequency-selective response under BCI conditions. The peak of the terminal load response voltage occurs at frequencies corresponding to the integral multiples of half the relative length of the cable. The position of the current probe along the cable only affects the amplitude of the distributed current on the shielding layer, but not its distribution pattern. The response of the internal core wire at the resonant frequencies is positively correlated with the distribution pattern of the distributed current on the shielding layer. The probe position has a significant effect on the magnitude of the wire-to-terminal response. Placing the current probe at both ends of the cable results in high injection efficiency and significant power savings.