Power System 5

Electrical Engineering MCQ Question Papers: Campus Placement

Subject: Power System 5

Part 5: List for questions and answers of Power System

Q1. Communications lines are treated as

a) Short transmission lines

b) Long transmission lines

c) Medium transmission lines

d) Any of the above

Q2. If the rated receiving end voltage is 33 kV, then what are the limits for safe operation of equipments?

a) 33 to 50 kV

b) 25 to 35 kV

c) 31.35 to 34.65 kV

d) Any voltage above 33 kV

Q3. A 1-phase transmission line has an impedance (4 + 3j ) ohm. Find the power factor of the load for zero voltage regulation?

c) 0.6 lag

d) 0.8 lag

Q5. Which of the following transmission line is most practically used in load flow analysis?

a) Nominal T

b) Nominal ?

c) Either 1 or 2

d) Nether 1 nor 2

Q6. Transmission line has a length of 300 km, operating at sending end voltage Vs = 1 pu, find the receiving end voltage(Vr) at no load?

a) 1 pu

b) 0.98 pu

c) 1.098 pu

d) 0.098 pu

Q7. Installation of capacitors at suitable locations and of optimum size in a distribution system results in

a) Improved voltage regulation

b) Reduction in distribution power loss

c) Reduction of KVA rating of distribution transformers

d) All of the above

Q8. Ferranti effect occurs under

d) Any of the above

Q9. If transmission line parameters A and B are 0.9  0 deg. and 200  90 deg. respectively. Find the shunt reactor required to compensate the ferranti effect?

a) 1500 ohm

b) 3000 ohm

c) 750 ohm

d) 2000 ohm

Q10. In a long transmission line, if we increase the length of the line, the parameters A and B respectively

a) Increases and increases

b) Decreases and decreases

c) Decreases and increases

d) Increases and decreases

Q11. Power transmission lines are transposed to reduce

a) Skin effect

b) Proximity effect

c) Ferranti effect

Q12. Find the propagation constant, if impedance is 10 ohm and admittance is 10 a;s

a) 100

b) 1

c) 10

d) 5

Q13. Attenuation occurs due to

a) Resistance

b) Inductance

c) Conductance

d) Both 1 and 3

Q14. Phase shift occurs due to which of the following components?

a) Inductance

b) Capacitance

c) Both 1 and 2

d) Conductance

Q15. A loss less transmission line has a length of 600 km, find the phase shift of voltage signal?

a) 90 deg.

b) 42 deg.

c) 36 deg.

d) 45 deg.

Q16. A transmission line is operating under no load has ABCD parameters B = 100<90 deg. has a phase shift of 0.2 rad, how much shunt reactor is required for compensation of ferranti effect?

a) 2 mH

b) 15.9 mH

c) 15.9 H

d) 2 H

Q17. A transmission line has a surge impedance of 400 ohm for a length of the line of 200 km. If the length of line is increased to 400 km, then its surge impedance is

a) 400 ohm

b) 800 ohm

c) 200 ohm

d) 0 ohm

Q18. Counter poise is used for

a) Proper discharging of lighting surges

b) More surge impedance

c) Less surge impedance

d) Reduce losses

a) Increasing of voltage level

b) Increasing of capacitance value

c) Both 1 and 2

d) Increasing of inductance value

Q20. A transmission line is compensated with shunt capacitance Csh. After shunt compensation surge impedance loading will

a) Increases

b) Decreases

c) Remains unaffected

d) None of the above

Part 5: List for questions and answers of Power System