Ripple current in the chopper circuit :Ripple current is the difference between maximum current (Imx) and minimum current (Imin) flowing through the chopper circuit in the steady-state operation of the chopper.
The ripple current of chopper operating in steady-state is given by
Where
α = duty cycle of the chopper, V
s = DC supply voltage, R = load resistance, T
a = time constant = L/R , and T = time period of the chopper
From the above equation, we can observe per unit ripple current is only depends on the time constant (T
a), Time period (T), and duty cycle (α ).
Variation of ripple current with a duty cycle (α) and T/Ta ratio:We can observe the variation of ripple current with duty cycle and T/T
a ration in the figure is shown below,