400 Important Transmission and Distribution MCQ Question and Answer | PDF Free Download
1.When the characteristic impedance of a transmission line is equal to the load impedance
- AThe system will resonate badly.
- BAll the energy sent will be absorbed by the load.
- CAll the energy sent will pass to the earth.
- DAll the energy will be lost in transmission line as transmission losses.
2.The Characteristic impedance of transmission line
- AIncreases with increase in length
- BDecreases with the length of line
- CIndependent of Line length
- DNone of the above
3.The surge impedance value of an overhead line usually in the range of
- A100 ohms ? 200 ohms
- B200 ohms ? 300 ohms
- C400 ohms ? 500 ohms
- D0 ohms ? 100 ohms
4.The Surge impedance of a 400 kV , 100 km transmission line is 300 ohms. For a 200 km length the line Surge impedance will be
- A300 ohms
- B150 ohms
- C600 ohms
- D400 ohms
5.A transmission line is distortion-less if
- ARG = LC
- BRC = GL
- CR/C = G/L
- DR = G
6.When the load on a transmission line is equal to the surge impedance loading
- AThe receiving-end voltage is less than the sending-end voltage.
- BThe sending -end voltage is less than the receiving -end voltage.
- CThe receiving-end voltage is equal to the sending-end voltage.
- DNone of these.
7.The Surge impedance loading SIL of a single circuit 220 kV line is about
- A120 MW
- B90 MW
- C220 MW
- D400 MW
8.A lossless radial transmission line with Surge impedance loading
- ATakes negative VAR at sending end and zero VAR at receiving end.
- BTakes positive VAR at sending end and zero VAR at receiving end.
- CHas flat voltage profile and unity power factor at all points along it.
- DHas sending end voltage higher than receiving end voltage and unity power factor at sending end
9.What does the standing wave ratio (SWR) of unity imply?
- ATransmission line is open-circuited.
- BTransmission line is short-circuited.
- CTransmission line?s characteristic impedance is equal to load impedance.
- DTransmission line?s characteristic impedance is not equal to load impedance.
10.Full-load compensation in a transmission line requires
- AShunt capacitors
- BSeries capacitors
- CTransformers
- DShunt reactors
11.To increase the transmission capability of a high voltage long line
- AThe resistance can be increased
- BThe resistance can be decreased
- CThe series reactance can be reduced
- DThe shunt admittance can be reduced
12.Power dispatch through a transmission line can be increased by
- AInstalling series capacitor
- BInstalling shunt capacitor
- CInstalling series reactor
- DInstalling shunt reactor
13.The power transmitted will be maximum when
- ALine reactance is high
- BCorona losses are minimum
- CSending end voltage is more
- DReceiving end voltage is more
14.For constant voltage transmission, the voltage drop along the line is maintained constant by installing
- ACapacitors
- BInductors
- CResistors
- DSynchronous phase modifiers at receiving end
15.Constant voltage transmission have the advantages of
- AAvailability of steady voltage at all loads at the receiving end.
- BPossibility of better protection for the line due to possible use of higher terminal reactances.
- CPossibility of carrying increased power for a given conductor size in case of long distance heavy power transmission.
- DAll of the above.
16.When the sending end voltage and current are numerically equal to the receiving end voltage and current respectively, then the line is called
- AA tuned line
- BA transposed line
- CA long line
- DA short line
17.A synchronous conductor is a
- ASynchronous generator
- BPaper condenser
- CSynchronous motor
- DNone of these
18.A synchronous compensator absorbs inductive reactive power. It is
- AOverexcited
- BNormally excited
- CUnderexcited
- DNone of these
19.A synchronous phase modifier as compared to synchronous motor of the same rating has
- ALarger shaft diameter and higher speed.
- BSmaller shaft diameter and higher speed.
- CLarger shaft diameter and Smaller speed.
- DSmaller shaft diameter and Smaller speed.
20.Phase modifier is normally installed in case of
- AShort transmission lines
- BMedium length lines
- CLong transmission lines
- DFor any length of lines