6.1 Chopper

Chopper converts

• AC to DC

• DC to AC

• DC to DC

• AC to AC

A chopper may be thought as a

• Inverter with DC input

• DC equivalent of an AC transformer

• Diode rectifier

• DC equivalent of an induction motor

4. Which device cannot be used in a chopper circuit?

• BJT

• MOSFET

• GTO

• Diode

The power device used in a chopper is a

• Time ratio controller

• AC to DC converter

• DC transformer

• High speed semiconductor switch

What is the duty cycle of a chopper ?

• Ton/Toff

• Ton/T

• T/Ton

• Toff x Ton

The load voltage of a chopper can be controlled by varying the

• Duty cycle

• Firing angle

• Commutation angle

The values of duty cycle (α) lies between

• 0<D<1

• 0>D>-1

• 0<=D<=1

• 1<D<100

If T is the time period for a chopper circuit and α is its duty cycle, then the chopping frequency is

• Ton / D

• Toff / D

• D / Toff

• D / Ton

For a step down chopper

• Vo = Vs

• Vo < Vs

• Vo > Vs

For a step up chopper

• Vo = Vs

• Vo < Vs

• Vo > Vs