The power electronic converter shown in the figure given

The power electronic converter shown in the figure given below has a single-pole double-throw switch. The pole P of the switch is connected alternately to throws A and B. The converter shown is a

1. step-down chopper (buck converter)
2. half-wave rectifier
3. step-up chopper (boost converter)
4. full-wave rectifier

Let Duty cycle be ‘D’.
When at A : t = 0

V_in = L	di	+ V_out , (i_L)_in =	(V_in - V₀)	DT
	dt		L

When at B : At t = DT

V_out = -V_L =	-Ldi_L
	dt

(i_L)_off =	-V_out	(1 - D)T
	L

(V_in – V_out) DT + (– V_out) (1 – D)T = 0
⇒ (V_in – V_out) D = V_out(1 – D)
⇒ V_out = DV_in and D < 1
So, step down chopper.