Explore topic-wise MCQs in Power Electronics.

This section includes 10 Mcqs, each offering curated multiple-choice questions to sharpen your Power Electronics knowledge and support exam preparation. Choose a topic below to get started.

1.

For the same triggering angle and ratings

A. a semi-converter operates at lower output voltage than a full converter
B. a semi-converter operates at higher output voltage than a full converter
C. a semi-converter has lower values of input p.f as compared to a full converter
D. a semi-converter has more THD as compared to a full converter
Answer» C. a semi-converter has lower values of input p.f as compared to a full converter
2.

A single-phase semi-converter circuit is supplying power to a motor load. The average value of load voltage is 176.72 V and the rms value is 219.3 V. Find the VRF (voltage ripple factor).

A. 0
B. 0.735
C. 0.569
D. 2.48
Answer» C. 0.569
3.

A single-phase semi-converter is connected to a 230 V source and is feeding a load R = 10 Ω in series with a large inductance that makes the load current ripple free. For α = 45°, find the rectification efficiency. The RMS value of output voltage is 219.3 V

A. 96.54 %
B. 75.25 %
C. 89.45 %
D. 80.58 %
Answer» E.
4.

A single-phase semi-converter is connected to a 230 V source and is feeding a load R = 10 Ω in series with a large inductance that makes the load current ripple free. Find the average output current for α = 45°.

A. 14 A
B. 17 A
C. 10 A
D. 0 A
Answer» C. 10 A
5.

In any AC-DC circuit, the freewheeling action

A. improves the power handling capabilities
B. increases the THD
C. improves CDF
D. all of the mentioned
Answer» D. all of the mentioned
6.

For the circuit shown below, T1 and T2 (from top T1 and T2) are both fired at an angle α. Then from ωt = π to ωt = π+α

A. None of the devices conduct
B. T1 and one diode will conduct
C. T2 and one diode will conduct
D. Both the diodes will conduct
Answer» E.
7.

Find the circuit turn-off time (Tc) for the below given semi-converter configuration. Take α = 30° and Vs = 230√2 sin100t

A. 20π radians
B. 5π/6 radians
C. for the below given semi-converter configuration. Take α = 30° and Vs = 230√2 sin100ta) 20π radiansb) 5π/6 radiansc) π/120 radians
D. 3/π radians
Answer» D. 3/π radians
8.

In the below given circuit, from ωt = π to α+π and continuous load current configuration

A. T1 and T2 conduct
B. T2 and D1 conduct
C. T1 and D2 conduct
D. T1 and D1 conduct
Answer» D. T1 and D1 conduct
9.

A single-phase asymmetrical semi-converter employs

A. one SCR and one diode in each leg
B. two SCRs in one leg and two diodes in the other
C. two SCRs in both the legs
D. two diodes in both the legs
Answer» C. two SCRs in both the legs
10.

A single-phase symmetrical semi-converter employs

A. one SCR and one diode in each leg
B. two SCRs and two diodes in each leg
C. two SCRs in each leg
D. two diodes in each leg
Answer» B. two SCRs and two diodes in each leg