Electromagnetic topology analysis on relation between electromagnetic interference inside equipment and external electrostatic discharge

Simulation based on electromagnetic topology theory was applied to analyze the relationship between internal electromagnetic interference (EMI) and external electrostatic discharge (ESD) of semi-shielded electrical equipment. The topological structure model of the equipment was built to analyze the coupling paths of external disturbance. To the aperture coupling path, a new method was adopted to determine the transfer function between external disturbance and internal sensitive component, which was modeled as a wire conductor in this paper. The simulation result shows that the EMI induced by external ESD on the wire conductor depends on its length and location. The results compare well with previous reports.