Mike explained why ESL (equivalent series inductance) or LSER (series inductance) not implemented in Qspice. You won’t find series inductance parameter in Pspice, Hspice, NGspice, TINA-TI etc… but only in LTspice.
For any type of film capacitor, it is more of a distributed Rser/Rpar/Lser/Cpar network. Poorly described with a single lumped series L. For a ceramic capacitor, a series inductance can be a more viable representation, but usually adds no accuracy to the simulation since connecting inductance often dominates. It was a mistake to support Lser as a part of a capacitor in LTspice. It did much more harm than good. Anyway, below would be a viable equivalent schematic of a film capacitor in lump…
I did not implement Lser for capacitors because it usually caused more harm than good.
A series inductance is not a great way to model the internal inductance of a capacitor. For foil capacitors, you really need a ladder of series R & L driving a distributed capacitance, though I’ve been able to match the complex impedance within a few degrees over several decades of frequency with just two lumps.
For ceramic capacitors, modeling their internal inductance is not really meaningful without mode…
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