In DC chopper, per unit ripple is maximum when duty cycle α is

In DC chopper, per unit ripple is maximum when duty cycle α is

Right Answer is:

0.5

SOLUTION

The Per unit ripple of DC Chopper is given as

Where

D = Duty Cycle = Ton/T

T = Chopping period

τ = Time constant = L/R

The ripple current is maximum if the differentiation of the above equation with respect to D is equal to zero.

Hence the ripple in load current is maximum when duty cycle D = 0.5 as shown in Fig. 

For duty cycle at= 50% (i.e. α= 0.5) and T/τ= 5, per unit ripple current become 0.848. Similarly for a= 0.5 and T/τ = 25, per unit ripple current = 1. In this way, the variation of per unit ripple current as a function of duty cycle α and T/τ can be plotted.

Scroll to Top