Rectifier Numericals MCQs

Practice Rectifier Numericals MCQs with four options, answers and explanations for focused Electronics & Telecommunication Engineering revision.

Question 1

Power ElectronicsRectifier Numericals

For a single-phase half-wave controlled rectifier with resistive load and supply peak Vm, the average output voltage is?

AVm(1+cos alpha)/(2pi)
B2Vm cos alpha/pi
CVm sin alpha/pi
DVm(1-cos alpha)/pi

Show AnswerHide Answer Report an error

Correct Answer: A. Vm(1+cos alpha)/(2pi)

Explanation: Averaging Vm sin(theta) from alpha to pi over a full 2pi period gives Vdc=Vm(1+cos alpha)/(2pi).

Reference: Standard power electronics: rectifier numericals

Question 2

Power ElectronicsRectifier Numericals

A single-phase half-wave controlled rectifier has Vm=100 V and alpha=60 degrees with an R load. Its average output voltage is approximately?

A11.9 V
B23.9 V
C47.7 V
D75 V

Show AnswerHide Answer Report an error

Correct Answer: B. 23.9 V

Explanation: Vdc=100(1+cos60°)/(2pi)=150/(2pi)≈23.9 V.

Reference: Standard power electronics: rectifier numericals

Question 3

Power ElectronicsRectifier Numericals

A single-phase full converter has Vm=200 V and firing angle alpha=60 degrees. With continuous current, its average output voltage is approximately?

A31.8 V
B63.7 V
C100 V
D127.3 V

Show AnswerHide Answer Report an error

Correct Answer: B. 63.7 V

Explanation: Vdc=(2×200/pi)cos60°=200/pi≈63.7 V.

Reference: Standard power electronics: rectifier numericals

Question 4

Power ElectronicsRectifier Numericals

A single-phase semi-converter has Vm=100 V and alpha=60 degrees. Its average output voltage is approximately?

A23.9 V
B31.8 V
C47.7 V
D63.7 V

Show AnswerHide Answer Report an error

Correct Answer: C. 47.7 V

Explanation: Vdc=100(1+0.5)/pi=150/pi≈47.7 V.

Reference: Standard power electronics: rectifier numericals

Question 5

Power ElectronicsRectifier Numericals

If the average output voltage of an ideal single-phase full converter is 100 V and the continuous DC load current is 5 A, the average DC output power is?

A20 W
B100 W
C500 W
D1000 W

Show AnswerHide Answer Report an error

Correct Answer: C. 500 W

Explanation: For constant/continuous DC-side current, average output power P=Vdc Id=100×5=500 W.

Reference: Standard power electronics: rectifier numericals

Question 6

Power ElectronicsRectifier Numericals

A three-phase full converter is supplied from 400 V line-to-line RMS with alpha=0 degrees. Its ideal average DC output is approximately?

A270 V
B400 V
C540 V
D660 V

Show AnswerHide Answer Report an error

Correct Answer: C. 540 V

Explanation: Vdc=1.35×400×cos0°=540 V.

Reference: Standard power electronics: rectifier numericals

Question 7

Power ElectronicsRectifier Numericals

The same 400 V three-phase full converter operated at alpha=60 degrees has ideal average DC output of approximately?

A135 V
B270 V
C400 V
D540 V

Show AnswerHide Answer Report an error

Correct Answer: B. 270 V

Explanation: Vdc=1.35×400×cos60°=270 V.

Reference: Standard power electronics: rectifier numericals