# DC to DC Conversion MCQ [Free PDF] – Objective Question Answer for DC to DC Conversion Quiz

1. Choppers are used to control the DC voltage level.

A. True
B. False

Choppers are used to control the DC voltage level. They can increase, decrease or both the input DC voltage.

2. Which one of the following devices is uncontrolled?

A. SCR
B. MOSFET
C. Diode
D. TRIAC

A diode is an uncontrolled, unidirectional power electronic device. When the voltage across the diode becomes positive it starts conduction otherwise remains off.

3. Cuk-converter is better than the Buck converter in terms of the output voltage.

A. True
B. False

Cuk-converter is better than Buck converter in terms of the output voltage. The filter is present at the output and input side of the Cuk-converter whereas in Buck there is no filter circuit present on the input side.

4. What is the formula for output voltage for Buck converter?

A. 8D×Vin
B. 5D×Vin
C. 2D×Vin
D. D×Vin

The output voltage of the buck converter is Vo = D×Vin. The value of the duty cycle is less than one which makes the Vo < Vin. The buck converter is used to step down voltage. Vin is a fixed voltage and Vo is a variable voltage.

5. What is the formula for output voltage for the Buck-Boost converter?

A. D×Vin
B. Vin ÷ (1-D.
C. D×Vin ÷ (1-D.
D. D×Vin ÷ (1+D.

The output voltage of the buck-boost converter is Vo = D×Vin ÷ (1-D). It can step up and step down the voltage depending upon the value of the duty cycle.

If the value of the duty cycle is less than .5 it will work as a buck converter and for a duty cycle greater than .5 it will work as a boost converter.

h({});

6. What is the formula for output voltage for Boost converter?

A. 8D×Vin
B. 5D×Vin
C. 2D×Vin
D. D×Vin

The output voltage of the boost converter is Vo = Vin ÷ (1-D. The value of the duty cycle is less than one which makes the Vo > Vin. The boost converter is used to step up the voltage. Vin is a fixed voltage and Vo is a variable voltage.

7. ____________ is the boundary for C.C.M and D.C.M mode in 3-Φ Half wave bridge rectifier for R load.

A. 60°
B. 10°
C. 80°
D. 30°

30° is the boundary for C.C.M and D.C.M mode in 3-Φ Half wave bridge rectifier for R load. Conduction will only remain from 30°+α to 150°+α.

8. Buck-Boost acts as Buck converter for duty cycle is equal to _________

A. .9
B. .7
C. .6
D. .4

The output voltage of the buck-boost converter is Vo = D×Vin ÷ (1-D). It can step up and step down the voltage depending upon the value of the duty cycle.

If the value of the duty cycle is less than .5 it will work as a buck converter. The answer is .4.

9. Buck-Boost acts as Boost converter for duty cycle is equal to _________

A. .8
B. .1
C. .2
D. .4

The output voltage of the buck-boost converter is Vo = D×Vin ÷ (1-D). It can step up and step down the voltage depending upon the value of the duty cycle.

If the value of the duty cycle is more than .5 it will work as a boost converter. The answer is .8.

10. Inductor and Capacitor in Buck converter are used to ___________

A. Increase the cost
B. Decrease the cost
C. Filter out the harmonics
D. Increase the harmonics