Power Systems Multiple Choice Questions on “Inductance of One Conductor in a Group”.
1. Bundled conductors used in the EHV transmission lines result into __________
A. reduced inductance
B. increase capacitance
C. increase inductance
D. increase resistance
Answer: A
Clarification: Bundled conductors cause the GMR to increase and thus reducing the inductance.
2. The fictitious resistance, “ r’ ” implemented in the conductors for the calculation of the inductance is _____________
A. 0.7788r
B. 2r
C. r/0.7788
D. r
Answer: A
Clarification: It is 0.7788r in the equivalent network configuration.
3. (i) Skin effect
(ii) Proximity effect
Which of the options are right?
A. Both (i) and (ii) cause non uniform distribution of the current
B. Neither (i) and (ii) cause non uniform distribution of the current
C. Both (i) and (ii) cause uniform distribution of the current
D. Only (i) causes the non uniformity of the current
Answer: A
Clarification: Skin-effect as well as the Proximity effect cause the non distribution of the flux linkages, leading to non uniform distribution of the current.
4. Ferranti effect causes the non uniform distribution of the current and voltage.
A. True
B. False
Answer: B
Clarification: Only the voltage regulation is affected due to the Ferranti law.
5. Apart from the skin effect the phenomena which cause/s the non uniform distribution of the current is ____________
A. Proximity effect
B. Faraday’s effect
C. Ferranti effect
D. All of the mentioned
Answer: A
Clarification: Only the proximity effect and skin effect cause the non uniform distribution of the current.
6. Bundle conductor ______ inductance and ______ capacitance of a transmission line.
A. reduces, increases
B. increases, reduces
C. reduces, keeps constant
D. keeps constant, increases
Answer: A
Clarification: The inductance reduces by employing the bundle conductor.
7. For a transmission line, the distributed parameters is/are ____________
A. Resistance, inductance, capacitance
B. Resistance
C. Inductance, capacitance
D. None of the mentioned
Answer: A
Clarification: All R, L and C are considered distributed parameters.
8. As the frequency increases, the flux inside the conductor will ________
A. decrease
B. increase
C. be constant
D. be zero
Answer: A
Clarification: Skin effect is inversely proportional to frequency.
9. Self GMD and GMR vary with each other as __________
A. linearly
B. parabolic
C. exponential
D. none of the mentioned
Answer: D
Clarification: Because the self GMD and GMR are same quantities.
10. If the diameter of the conductor is increased then _____________
A. inductance increases
B. inductance remains unaltered
C. inductance decreases
D. inductance can’s be determined
Answer: A
Clarification: Inductance will increase.