question papper

1. Question Answer
1. Which semiconductor power device out of the following, is not a current triggering
device?
a. Thyristor
b. Triac
c. G.T.O
d. MOSFET
Answer- d) MOSFET
2. If the firing angle becomes negative, then the rectifier begins to work as
a. A rectifier
b. An inverter
c. A chopper
d. A regulator
Answer -b) An inverter
3. Transformer utilization factor is a measure of the merit of a rectifier circuit. It is the
ratio of
a. AC input power to the transformer volt - amp rating required by secondary
b. AC input power to the transformer volt - amp rating required by primary
c. DC output power to the transformer volt - amp rating required by secondary
d. DC output power to the transformer volt - amp rating required by primary
Answer – c) DC output power to the transformer volt - amp rating required by secondary
4. Which converter topology out of the following, is a non-isolated converter?
a. Flyback Converter
b. Cuk Converter
c. Push-pull Converter
d. Forward Converter
Answer -b) Cuk Converter
5. Which converter topology out of the following, is a single ended isolated converter?
a. Full-Bridge Converter
b. Half-Bridge Converter

2. c. Push-pull Converter
d. Forward Converter
Answer -d) Forward Converter
6. Consider the following device:
1)SCR 2) GTO 3) BJT 4) MOSFET 5) IGBT
Which of the following device do not belongs to family of transistor?
a. 1 and 2 only
b. 1,2 and 3 only
c. 2,3 and 5 only
d. 1,2,3,4 and 5
Answer - a) 1 and 2 only
7. Which of the following is the fastest switching devices?
a. JFET
b. BJT
c. Triode
d. MOSFET
Answer- d) MOSFET
8. A single -phase, voltage source, square wave inverter feeds a pure inductive load. The
waveform of current will be
a. Sinusoidal
b. Rectangular
c. Trapezoidal
d. Triangular
Answer- d) Triangular
9. Current source inverters are suitable for supply power to
a. RL loads
b. Inductive loads

3. c. All loads
d. Capacitive loads
Answer- d) Capacitive loads
10. Which of the following regulator provide output voltage polarity reversal without a
transformer?
a. Buck Converter
b. Cuk Converter
c. Buck-Boost Converter
d. Boost Converter
Answer- c) Buck-Boost Converter