Power Electronics MCQ Questions & Answers

51

How is the GTO turned off?

A) By using a commutation circuit B) By applying reverse gate pulse C) By using a latch circuit D) By reverse anode current pulse

Discuss

Answer & Solution

Answer: Option B

No explanation is given for this question. Let's Discuss on Board

52

A power diode has lightly doped n type substrate sandwiched between heavily doped p and n regions

A) to increase reverse breakdown voltage B) to reduce ohmic loss under forward bias C) to decrease switching time of the power diode D) to improve transient behaviour of the diode

Discuss

Answer & Solution

Answer: Option D

No explanation is given for this question. Let's Discuss on Board

53

An SCR has an anode supply of sine voltage 200 V_r.m.s, 50 Hz applied through a 100 Ω resistor and fired at an angle of 60°. Assuming no voltage drop, the r.m.s. value of the output voltage is nearly

A) 90 V B) 126 V C) 166 V D) 200 V

Discuss

Answer & Solution

Answer: Option B

No explanation is given for this question. Let's Discuss on Board

54

In the forward blocking region of a silicon controlled rectifier, the SCR is

A) In the off-state B) In the on-state C) Reverse biased D) At the point of breakdown

Discuss

Answer & Solution

Answer: Option A

No explanation is given for this question. Let's Discuss on Board

55

An SCR is sometimes called . . . . . . . .

A) Triac B) Diac C) Unijunction transistor D) Thyristor

Discuss

Answer & Solution

Answer: Option D

No explanation is given for this question. Let's Discuss on Board

56

Between the peak point and the valley point of UJT emitter characteristics we have . . . . . . . . region

A) Saturation B) Negative resistance C) Cut-off D) None of the above

Discuss

Answer & Solution

Answer: Option B

No explanation is given for this question. Let's Discuss on Board

57

The electronic circuit that converts AC to DC where the DC output peak value can be greater than the AC input peak value is-

A) Voltage multiplier B) Clipper C) Amplifier D) Clamper

Discuss

Answer & Solution

Answer: Option A

No explanation is given for this question. Let's Discuss on Board

58

A step down chopper is operated in the continuous conduction mode in steady state with constant duty ratio D. If V_o is the magnitude of the DC output voltage and if V_s is the magnitude of the DC input voltage, the ratio $$\frac{{{{\text{V}}_{\text{o}}}}}{{{{\text{V}}_{\text{s}}}}}$$ is given by

A) D B) 1 - D C) $$\frac{1}{{1 - {\text{D}}}}$$ D) $$\frac{{\text{D}}}{{1 - {\text{D}}}}$$

Discuss

Answer & Solution

Answer: Option A

No explanation is given for this question. Let's Discuss on Board

59

In thyristor, holding current is

A) More than latching current B) Less than latching current C) Equal to latching current D) Very small

Discuss

Answer & Solution

Answer: Option B

No explanation is given for this question. Let's Discuss on Board

60

Which one of the following can be used in the lighting system for power interruptions?

A) Diac B) Triac C) SCR D) SCS

Discuss

Answer & Solution

Answer: Option C

No explanation is given for this question. Let's Discuss on Board

Power Electronics MCQ Questions & Answers | ECE