In an analysis of buck converter, we make few assumptions. Those are:
- The circuit is operating in steady state.
- The inductor current is continuous.
- The capacitor is very large and the output voltage is held constant.
- The switching period is \$T\$; the switch is closed for time \$DT\$ and opens for time \$(1-D)T\$
- The components are ideal.
Here we say that the capacitor is very large to keep output constant.
How large, in Farads, should the capacitor be?