Average current mode control on secondary side of a transformer?

Thread Starter

SiCEngineer

Joined May 22, 2019
105
I have been looking through the famous app note on Average Current Mode Control by L. Dixon,https://e2echina.ti.com/cfs-file/__key/telligent-evolution-components-attachments/13-112-00-00-00-00-44-35/Average-Current-Mode-Control-of-Switching-Power-Supplies.pdf.

He gives many examples on how to use current mode control for input/output current and for flyback topology. I am quite novice when it comes to control theory, so I was wondering - is it possible to use average current control on the secondary side of an isolated DC/DC converter, such that we control what is essentially a "DC" current (with small ripple). My converter is a buck converter that is cascaded into a half bridge resonant converter, and controlling the buck output inductor current does not seem to be sufficient in regulating the converter under transient conditions. I thought maybe I could try controlling the secondary current and modulate the buck converter according to this for tighter control.

So, is it possible? Is it recommended?
 

Delta prime

Joined Nov 15, 2019
52
Can I see a schematic ?. Oddly enough my colleagues and I are developing (assessing strategies) of something similar. A current-mode converter with a secondary LC filter has been analyzed and modeled in “Secondary LC Filter Analysis and Design Techniques for Current-Mode-Controlled Converters” and “Three-Loop Control for Multimodule Converter Systems.” However, an assumption that the secondary inductor has a much smaller inductance value than the primary inductor, which is not always eligible in real applications..
 

Thread Starter

SiCEngineer

Joined May 22, 2019
105
Can I see a schematic ?. Oddly enough my colleagues and I are developing (assessing strategies) of something similar. A current-mode converter with a secondary LC filter has been analyzed and modeled in “Secondary LC Filter Analysis and Design Techniques for Current-Mode-Controlled Converters” and “Three-Loop Control for Multimodule Converter Systems.” However, an assumption that the secondary inductor has a much smaller inductance value than the primary inductor, which is not always eligible in real applications..
Hello mate! Apologies for the late reply. I will attach schematic to this reply. There is an additional CLC pi-filter on the output to remove ripple, so the document you sent I suppose could be applicable. I just can't get my head around the theory.
 

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