Dual-port pulsed differential-mode current injection method for high-level electromagnetic pulse radiated susceptibility testing

A dual-port pulsed differential-mode current injection (DPDCI) method is proposed for high-level wide-band electromagnetic pulse (EMP) radiated susceptibility testing of interconnected systems. By employing the designed wide-band differential-mode (DM) coupling device, the susceptibility of the equipment under test (EUT) at both ends can be assessed at the same time. In order to enforce the equivalence between EMP radiation and DPDCI, the methods to obtain the waveforms of the two equivalent injection sources and their time delay difference are proposed. By using the linear extrapolation method, the results for high-level EMP radiation can be reproduced by DPDCI even if the responses of the two EUTs are non-linear. To confirm the effectiveness of the proposed method, the conversion of common-mode interference into DM disturbance on the cable inside the EUT is assessed by experiment and the impact of connecting the injection devices into the system is discussed. By using a typical interconnected system composed of a coaxial cable and typical non-linear equipment at both ends, the feasibility of the proposed method is verified.