Difference Between the Partial Self-Inductance at DC and at HF

Abstract

The difference of the partial self-inductance of a single conductor is determined between two extremes of the frequency range: at dc and at HF (infinite frequency). They are first calculated separately for a finite large length. Both contain the same logarithm(length) singularity, but this disappears in their difference, which only involves the logarithm of the ratio of the equivalent radius and the geometrical mean distance. We have applied this to some common conductor cross sections: circle, ellipse, rectangle, and diamond and to the limit of zero thickness of these cross sections. In the latter case, a general expression is derived.

Highly accurate virtual dynamic characterization of discrete SiC power devices

“…Due to the skin and proximity effects, the resistance of a conductor increases with frequency and the inductance shows a decreasing trend [3]. With tendency to minimize the stray inductances of full SiC power module packages below 30 nH [4], there is a need to model the stray inductances of power module's interconnects with a very high accuracy and the difference between DC and AC inductance [5] must be taken into account. For low frequencies (referred to as DC range), Q3D employs a volume based FEM mesh assuming the current distribution at the full cross section of conductors, i.e.…”