hello, In a DC-DC boost converter during double-loop control process, CMC (Current mode control) why does the voltage control work better than VMC (voltage mode control) when load changes when the current is introduced as the inner loop feedback ?

hello, In a DC-DC boost converter during double-loop control process, CMC (Current mode control) why does the voltage control output come better than VMC (voltage mode control) when load changes when the current is introduced as the inner loop feedback ?

guide me please,

thank you

Answer 1

[John Noon]

Given enough effort, both VMC and CMC will be very high performance. However, generally CMC is "easier" to make high performance than VMC. This is because using CMC eliminates the filter resonance that is present in VMC control to output transfer function. Dr. Ray Ridley has a couple of helpful articles about this topic on his website: http://ridleyengineering.com/design-center-ridley-engineering/38-control/61-018-boost-converter-with-current-mode-control.html

http://www.ridleyengineering.com/design-center-ridley-engineering/38-control/60-017-boost-converter-with-voltage-mode-control.html

He describes this phenomena well in the first article that I liked to: "Finally, and most importantly, the current-mode boost converter retains the exact same RHP zero as the voltage-mode converter. However, since the current feedback has eliminated the double poles of the filter resonance, it is not difficult to control this RHP zero effectively."

I hope this helps!