Can anyone explain why (2Cdc) appears against each capacitor in the voltage source converter model (VSC-HVDC) connected to a local ac grid?
The Picture of VSC-HVDC model is attached. Can anyone explain why 2 capacitors are used at the output of VSC converter and how this 2Cdc appears against each capacitor in the attached picture? I have also seen that in some cases (Udc/2) appears against each capacitor in VSC-HVDC model? Can anyone explain this difference?

 

"2Cdc" is the capacitance value, not the voltage rating
Those 2C capacitors are in series, which is equivalent to a single 1C capacitor.

"Udc/2" is a voltage rating, meaning each capacitor experiences 1/2 of the Line Vdc

 

Hello,

You already have a thread for this :
Why value of DC capacitor in VSC-HVDC converter is (Vdc/2) in some cases and (2Cdc) in other cases?

Bertus