# 3-Phase Energy Recovery MCQ Questions & Answers

3-Phase Energy Recovery MCQs : This section focuses on the "3-Phase Energy Recovery". These Multiple Choice Questions (MCQs) should be practiced to improve the 3-Phase Energy Recovery skills required for various interviews (campus interview, walk-in interview, company interview), placement, entrance exam and other competitive examinations.

Question 1

1600 V rated 8 SCRs are connected in series. The operation voltage of the string is 4400. Calculate the string efficiency.

A. 34.37 %
B. 30.15 %
C. 38.48 %
D. 35.84 %

Question 2

Calculate Kinetic energy of the object of mass = 7 Kg moving in a straight line with a velocity of 12 m/s.

A. 504 J
B. 502 J
C. 503 J
D. 509 J

Question 3

Calculate the average value of thyristor current in 3-? Full wave converter for the load current=729 A and ?=3°.

A. 254 A
B. 285 A
C. 247 A
D. 243 A

Question 4

Calculate the coefficient of fluctuation of speed using the data: Vmax(Fluctuation)=25 m/sec, Vmean=12 m/sec.

A. 2.08
B. 2.16
C. 2.34
D. 2.74

Question 5

Calculate the line voltage for 3-? 120° VSI if the value of DC supply is 96 V.

A. 68.25 V
B. 67.87 V
C. 66.25 V
D. 62.14 V

Question 6

Calculate the maximum fluctuation of speed using the data: Vmax=23 m/sec, Vmin=13 m/sec.

A. 12
B. 10
C. 14
D. 15

Question 7

Calculate the phase voltage for 3-? 120° VSI if the value of DC supply is 78 V.

A. 30.45 V
B. 15.18 V
C. 31.84 V
D. 48.15 V

Question 8

Calculate the r.m.s value of thyristor current in 3-? Full wave converter for the load current=2 A and ?=59°.

A. 1.15 A
B. 2.55 A
C. 2.07 A
D. 2.89 A

Question 9

Calculate the rotational kinetic energy of the object using the data: I=5 Kg-m2, ?=25 rad/sec.

A. 1.46 KJ
B. 1.56 KJ
C. 2.58 KJ
D. 3.15 KJ

Question 10

Flywheel is analogous to ___________

A. Chemical battery
B. Mechanical battery
C. Nuclear battery
D. Electrostatic battery

Question 11

Full form of IGBT is ___________

A. Insulated gate bipolar transistor
B. Insulated gate bipolar transducer
C. Insulator gate bidirectional transducer
D. Insulated gate bidirectional transistor

Question 12

Full form of KERS is ___________

A. The kinetic energy recovery system
B. The kinetic ever recovery system
C. Kin ever recovery system
D. The kinetic energy recovery store

Question 13

Rectifiers are used to convert DC power into variable AC power.

A. True
B. False

Question 14

Short circuit problem is severe in case of current source inverter.

A. True
B. False

Question 15

1600 V rated 8 SCRs are connected in series. The operation voltage of the string is 4400. Calculate the string efficiency.

A. 34.37%
B. 30.15%
C. 38.48%
D. 35.84%

Question 16

Calculate the average value of thyristor current in 3-Φ Full wave converter for the load current=729 A and α=3°.

A. 254 A
B. 285 A
C. 247 A
D. 243 A

Question 17

Calculate the line voltage for 3-∅ 120° VSI if the value of DC supply is 96 V.

A. 68.25 V
B. 67.87 V
C. 66.25 V
D. 62.14 V

Question 18

Calculate the phase voltage for 3-∅ 120° VSI if the value of DC supply is 78 V.

A. 30.45 V
B. 15.18 V
C. 31.84 V
D. 48.15 V

Question 19

Calculate the r.m.s value of thyristor current in 3-Φ Full wave converter for the load current=2 A and α=59°.

A. 1.15 A
B. 2.55 A
C. 2.07 A
D. 2.89 A