Coupling efficiency analysis of current injection probe for bulk current injection

Coupling efficiency of a current injection probe has been quantitatively analyzed according to a degraded model, the analytic expressions of coupling efficiency at low, medium and high frequency bands are presented and the determinant factors of low and high cutoff frequency are obtained. A current injection clamp is designed, the specific turns determination and magnetic core selection procedure is introduced with the help of analytic result. The performance of the designed current injection clamp meets the requirement of relative standard and validates the analysis. This work can be used for the design theory of broadband current coupler.