Power System Planning and Design (2180903) MCQs

MCQs of Insulation co-ordination

Showing 21 to 30 out of 43 Questions
1 2 3 4 5
21.
In the presence of corona, electrostatic coupling ____________ and electromagnetic coupling ___________
(a) Decrease, increases
(b) Increases, decrease
(c) Increases, remains same
(d) Remains same, decrease
Answer:

Option (c)

22.
When a transmission line is energized, ___________ propagate on it
(a) Voltage wave only
(b) Current wave only
(c) Both (a) and (b)
(d) None of above
Answer:

Option (c)

23.
When a wave propagate on a transmission line, it suffers reflection several times at
(a) Load end
(b) Sending end
(c) Sending end and other end
(d) None of above
Answer:

Option (c)

24.
Travelling voltage wave and current wave have the same waveforms and travel together along the transmission line at a velocity
(a) Of sound
(b) Of light
(c) Slightly lesser than that of light
(d) Slightly lesser than that of sound
Answer:

Option (c)

25.
For a transmission line the standing wave ratio is the ratio of
(a) Peak voltage to RMS voltage
(b) Maximum current to minimum current
(c) Maximum voltage to minimum voltage
(d) Maximum impedance to minimum impedance
Answer:

Option (c)

26.
The steepness of the wave-front can be reduced by connecting
(a) An inductor in series with the line
(b) A capacitor between line and earth
(c) An inductor between line and earth or a capacitor in series with the line
(d) Both (a) and (b)
Answer:

Option (d)

27.
If the load impedance is 100 ohm and input impedance is 25 ohm, then the characteristic impedance of the transmission line is
(a) 40 Ω
(b) 50 Ω
(c) 60 Ω
(d) 70 Ω
Answer:

Option (b)

28.
The insulation strength of an EHV transmission line is mainly governed by
(a) Load power factor
(b) Switching over-voltages
(c) Harmonics
(d) Corona
Answer:

Option (b)

29.
The insulation coordination for UHV lines above 500 kV is done based on
(a) Lightning surges
(b) Switching surges
(c) Both (a) and (b)
(d) None of above
Answer:

Option (b)

30.
In comparison to line insulation, the insulation level of the station equipment is
(a) Less
(b) More
(c) Equal
(d) Not directly related to each other
Answer:

Option (d)

Showing 21 to 30 out of 43 Questions
1 2 3 4 5