SUBJECT to an assumption that the current pulse is perfectly rectangular if I understand

correctly.

I said just above your reply, "...discontinuous conduction..."; the

current pulse is not rectangular in that mode. See the image of the

current waveform for this mode in my most recent post on ABSE, but actually

it doesn't matter if the current pulse is perfectly rectangular.

That seems to be a very big assumption especially in the case of a flyback supply.

So it is. And, in fact, it's so strongly affected, that below a certain

duty cycle, the capacitor ripple current is greater than the output

current,

Which is entirely normal for ac line frequency power supplies for example at all power

levels..

and above that duty cycle, the capacitor ripple current is less

than the output current.

Yes, that bit did actually surprise me, but it's clear from examination of the

mathematical analysis, subject again to the assumption of a rectangular current

waveform.]

Again, I was talking about discontinuous conduction mode, but that doesn't

change the conclusion.

What would interest me more still is just how valid (or otherwise) that assumption is. I

feel some modelling coming on.

For all three modes which I analyzed, it's true that "...below a certain

duty cycle, the capacitor ripple current is greater than the output

current, and above that duty cycle, the capacitor ripple current is less

than the output current.".