DC-DC converter analysis

[paulmdrdo]

I am having a hard time doing a derivation for the DC component of the voltage across cap C2. It has to be in terms of source voltage Vg and duty cycle D. Please help me get started. I know the role of the cap is to reset the transformer so it would not saturate. So for the first interval the current IC2 is zero, so is voltage Vc2 (assuming zero initial condition). The analysis during second interval gives a hard time. The voltage across

 

[biswaIITH]

I am having a hard time doing a derivation for the DC component of the voltage across cap C2. It has to be in terms of source voltage Vg and duty cycle D. Please help me get started. I know the role of the cap is to reset the transformer so it would not saturate. So for the first interval the current IC2 is zero, so is voltage Vc2 (assuming zero initial condition). The analysis during second interval gives a hard time. The voltage across
View attachment 163527

This is an active clamped forward converter. The above clamp is a fly-back clamp/buck-boost type.

When the switch-1 is on, the input current plus the output reflected current flows through the transformer. When the switch is off ,it stores the energy in the capacitor C2 through the switch-2.

If you apply basic voltage equations, u will get Vc2= Vg *(D/1-D)..