Image
1.0.0
MCQ
41. Surge impedance loading of a 3-phase, 400k Y transmission line is 4002. The surge impedance loading is-
400MW
1600MW
800MW
200MW
42. The skin effect of conductor will increase when-
diameter decrease
resistivity decrease
frequency decrease
all of the above
43. The main objectives of electrical power transmission is/are-
Transmission system must be more efficient with minimum line losses
Voltage regulation of the transmission line must be zero or minimum
both 1 and 2
neither I nor 2
44. If sparsity of a 5 bus transmission line is 0.4. Find the number of transmission lines--
6
5
8
3
45. Ferranti effect will not occur in which of the following transmission lines-
long transmission lines
short transmission lines
medium transmission lines
all of the above
46. Which of the following methods is/are used for reactive or voltage compensation?
shunt capacitor
generation excitation control
series capacitor
all of the above
47. Galvanised steel is generally used as--
stray wire
earth wire
structural components
all of the above
48. Advantages of higher trans mission voltage is/are--
Power transfer capability of the transmission line is increased
Transmission line losses are reduced
Area of cross section and volume of the conductor is reduced
all of the above
49. Maximum power transfer capability of transmission line can be increased by-
Parallel transmission lines
Using series capacitance
Using bundled conductors
all of the above
50. ACSR means-
Aluminium core steel reinforced
Aluminium conductor steel reinforced
Aluminium copper steel reinforced
reinforced all conductor steel
ব‍্যাখ্যা: ACSR = Aluminium conductor steel reinforced.
51. Ferranti effect can be compensated by which of the following?
series capacitor
shunt capacitor
all of the above
none
52. Under excited synchronous phase modifier works as-
shunt capacitor
shunt reactor
series capacitor
any of the above
53. Which of the following method is used for changing power factor from leading to lagging?
shunt capacitor
series capacitor
shunt reactor
any of the above
54. For flat voltage profile system, voltage regulation is-
0%
100%
200%
50%
55. The presence of earth in case of overhead lines-
increase inductance
increase capacitance
decrease inducatance
decrease capacitance
ব‍্যাখ্যা: As the earth is considered to be an infinite source of electrons, the presence of overhead lines causes charge currier to be separated by a dielectric (air), causing an increase in capacitance.
56. The charging reactance of 50km transmission line is 1500Ω. What is the charging reactance for 100km length of line?
1500 Ω
750 Ω
300 Ω
1000 Ω
57. Which of the following statement is true?
At higher voltage, cost of transmission is reduced
At higher voltage, cost transmission is increased
efficiency decreased
all of the above
58. Maximum power transfer in a transmission line can be obtained by—
increasing voltage level
reducing reactance
either 1 or 2
none of the above
59. Under over excitation synchronous phase modifier works as-
shunt capacitor
series capacitor
shunt reactor
any of the above
60. Stability of a transmission line can be increased by—
shunt capacitor
shunt reactor
series reactor
both 1 and 2