Derating of semiconductor fuselinks for use in high-frequency applications

High-breaking-capacity fuselinks used in high-frequency power inverter (50 kHz) circuits sometimes operate spuriously below rated current. Premature melting is more common when the fuselinks are mounted near associated cables or semiconductors. This unexpected operation can be attributed to skin and proximity effects, which are consequences of the electromagnetic induction between parallel current-carrying conductors. To prevent undue action of the fuselinks, their ratings must be reduced in accordance with a function of frequency, fuse dimensions and the distance between the fuselink and current-carrying conductors.