Simulations of the transient electromagnetic field in exploding foil initiator

A special high pulsed current is required in the Exploding Foil Initiator (EFI). The pulsed current would reach several thousand amperes, and this process will arouse strong electromagnetic interference (EMI) to the control units near around. Ever since EFI´s appearance, it has been designed with the targets of lower volume, higher integration, energy and cost effectiveness. Thus, this strong EMI is a bottleneck of the miniaturization development of EFI. In this paper, the characteristic curve of the pulsed current was calculated out, and then loaded on the equivalent wire of the circuit. The transient electromagnetic field around the conducting wire has been simulated out for the first time. The variation of induced electric field (EF) in different directions was plotted. All the 3D models and simulations are carried out using the Finite Element Method (FEM) software-ANSYS. Besides, the simulation result has been verified through a designed test. The final conclusions obtained in this work are highly meaningful for the EMI protection of EFI. Based on the data of radiated EMF, further protection method of different electronic components can be analyzed according to their thresholds.