Parasitic Capacitance in Copper-Foiled Medium-Voltage Filter Inductors

Abstract

This paper characterizes three parasitic capacitances in copper-foiled medium-voltage inductors. It is found that the conventional modeling method overlooks the effect of the fringe field, which leads to inaccurate modeling of parasitic capacitances in copper-foiled inductors. To address this problem, the parasitic capacitances contributed by the fringe field is identified first, and a physics-based analytical modeling method for the parasitic capacitances contributed by the fringe field is proposed, which avoids using any empirical equations. The total parasitic capacitances are then derived for three different cases with three different core potentials, from which a three-terminal equivalent circuit is derived, and thus, the parasitic capacitances in copper-foiled inductors are explicitly identified. The calculated results show a close agreement with the measured capacitance by using an impedance analyzer.

Parasitic Capacitive Couplings in Medium Voltage Power Electronic Systems: An Overview

“…Stored energy ratio of parasitics as a function of Spara for a LV Si IGBT power module [58] and a MV SiC MOSFET power module [21]. [76]. indicates the two voltage class transistor types comparable in power rating; the MV SiC MOSFET power module [21] and the LV IGBT power module [58] respectively.…”

“…In [76] the increase in switching energy dissipation is quantified by evaluating the impact of intra-component capacitive couplings between power module B, from [52] populated with 10 kV 3 rd generation Cree dies, and the load inductor, using different grounding configurations of inductor core and frame with different equivalent capacitive coupling magnitudes, and testing at different voltage levels. The results are summarized in Table I where it is shown how an increase in parasitic capacitance has a direct impact on the semiconductor switching energy dissipation.…”