Protection Characteristics of Ferrite Magnetic Ring against HEMP and Lightning

In order to study the ability of the ferrite magnetic ring to combined protection to the high altitude electromagnetic pulse (HEMP) and lightning, this paper studies the HEMP and lightning protection of ferrite magnetic ring based on an 500 kV open-type substation by experiment of PSCAD program. The results show that the ferrite magnetic ring can suppress the magnitude of the intrude current, effectively filter out the high-frequency components of HEMP conduction current, and supply the protection of typical surge protective devices. Design the size and the placement of magnetic ring according to the specific application condition, can better play the ferrite magnetic ring on the excellent combined protection characteristics against HEMP and lightning.