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Design >> High-Power Design >> Why the inductor pole has moved to high frequencies in peakcurrent-mode control?
https://designers-guide.org/forum/YaBB.pl?num=1329142224

Message started by AnilReddy on Feb 13^th, 2012, 6:10am

Title: Why the inductor pole has moved to high frequencies in peakcurrent-mode control?
Post by AnilReddy on Feb 13^th, 2012, 6:10am

hi all,

In peak-current mode control of any power converter, how to calculate the exact location of the pole caused by the inductor without using small inductor current-ripple approximation?

Normally, in average current-mode control, if we use small current-ripple approximation for the inductor we say that the inductor current will be constant and the inductor acts like a dc current source and thereby moving it's pole to infinity(ideally). But, how could this happen in peak or valley current mode control if we we don't use small-ripple approx.?

Thanks
Anil

Title: Re: Why the inductor pole has moved to high frequencies in peakcurrent-mode control?
Post by thomasross20 on Oct 3^rd, 2012, 9:29am

I've got to admit I always start to read papers on this then stop after encountering some obscure maths. Perhaps I need to sit down and truly work through state-space equations and the like.

I don't know about exact numbers but I *think* the pole is the same as the BW of the current loop (because when the current loop stops working you no longer have proper current control taking the inductor out). Or maybe I'm wrong..!