# Which of the following is used for power factor improvement in transmission line ?

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Which of the following is used for power factor improvement in transmission line ? (a) Three phase induction (b) An overexcited three phase synchronous motor running on no load (c) Three phase AC series motor (d) Choke

## Related questions

Which of the following relations is true for long transmission line ? (a) VS = AVR – BIR (b) VS = BVR + AIR (c) VS = AVR + BIR (d) VS = BVR – AIR

For a short transmission line with r/x ratio of is 1.0, the regulation will be zero when the load power factor is

In case the height of transmission tower is increased, which of the following parameter is likely to change?  (A) Resistance (B) Inductance (C) Capacitance (D) None of the above

What type of insulator will be used if the direction of the transmission line is to be changed?

In which of the following transmission lines, the value of the Shunt admittance should be approximated to zero ? (A) A 66 kV 35 km long line (B) A 132 kV 200 km long line (C) A 220 kV 300 km long line (D) A 400 kV 500 km long line

The power loss in a transmission line depends on (a) current in the line. (b) resistance of the line. (c) length of the line. (d) All of the above

How many insulator disc used for 33 kV transmission voltage line?

The inductance of single phase two wire power transmission line per km gets doubled when the  (a) Distance between wires is doubled  (b) Distance between the wires is increased four fold  (c) Distance between the wires is increased as square of the original distance  (d) Radius of the wire is doubled

The inductance of a power transmission line increases with (A) decrease in line length. (B) increase in conductor diameter. (C) increase in spacing between phase conductors. (D) increase in load current carried by conductors.

In a transmission line if booster transformers are to be used, preferred location will be  (A) At the receiving end (B) At the sending end (C) At the intermediate point (D) Anywhere in the line

In an AC transmission line difference in phase of voltage at two ends of the line is due to (a) System voltage (b) Insulators (c) Resistance of line (d) Reactance of line

The main consideration for operating transmission line at high voltage is (a) to increase efficiency only. (b) to reduce power loss only. (c) to increase power transmission capability only. (d) All of the above

State the working principle and operation of Automatic power factor controller used in Transmission and Distribution system.

To increase power transfer capability of a long transmission line, we should:  (1) Increase line resistance (2) Increase transmission voltage (3) Decrease line reactance (4) Both (2) & (3)

For a balanced three phase star connected load for which line voltage is 230V and per phase resistance and reactance is 6 Ohm and 8 Ohm respectively. Calculate: 1) phase voltage 2) line current 3) power factor 4) total power absorbed

Effect of increase in temperature in an overhead transmission line is (a) to increase stress and length both (b) to decrease stress and length both (c) to decrease stress and increase length (d) None of the above

Which of the following is TRUE with respect to HVDC transmission line? (A) For a short distance it is economical over HVAC. (B) In HVDC system, harmonics are not generated. (C) Use of HVDC can improve system stability. (D) Less and cheap terminal, equipments are required in HVDC.

The presence of earth in case of overhead transmission line (a) increases capacitance (b) increases inductance (c) decreases capacitance (d) decreases inductance

how the booster is connected in transmission line ?

For a fixed value of complex power flow in a transmission line having a sending and voltage V, the real power loss will be proportional to  A) V B) v2 C) 1/V2 D)1/V

For enhancing the power transmission in along EHV transmission line, the most preferred method is to connect a  (A) Series inductive compensator in the line (B) Shunt inductive compensator at the receiving end (C) Series capacitive compensator in the line (D) Shunt capacitive compensator at the sending end

Which of the following is true for a bus impedance matrix ?  (A) It is sparse  (B) It has diagonally dominant elements  (C) It is the inverse of the bus admittance matrix  (D) Each element of it is the reciprocal of the corresponding element in admittance matrix

If diameter of each conductor of a transmission line is ‘d’, then the diameter of n-layer stranded conductor will be (a) (2n – 1) d (b) (2n + 1) d (c) (3n – 1) d (d) (3n + 1) d

An overhead transmission line has a span of 260 m. The weight of the conductor is 0.68 kg/m. The maximum allowable tension in the line is 1550 kg. Maximum sag of the line should be (a) 5.8 m (b) 4.6 m (c) 2.7 m (d) 3.7 m

The input impedance of a short circuited loss less transmission line of characteristic impedance 50 Ohm is

A synchronous condenser is used at the receiving end of a transmission line for (A) supplying lagging kVA (B) voltage control (C) frequency control (D) maintaining a higher voltage than at the sending end

A three phase transmission line delivers a load of 5 MW at 0.8 power factor lagging. Resistance of each conductor is 0.5 ohm / km. Receiving end voltage is 33 kV. If the line loss is not to exceed 10%, determine the length of the line.  (A) 7 km (B) 27.9 km (C) 56.8 km (D) 13.9 km

An HVDC link consist of rectifier, inverter transmission line and other equipments. Which one of the following is true for this link ?  (A) The transmission line produces/ supplies reactive power (B) The rectifier consumes reactive power and the inverter supplies reactive power from/ to the respective connected ... power to/ from the respective connected AC systems (D) Both the converters (rectifier and inverter) consume reactive power from the respective connected AC systems

The bundled conductor in EHV transmission line system provides (a) increased inductance (b) reduced capacitance (c) increased capacitance (d) increased voltage gradient

For a transmission line open circuit and short circuit impedances are 20 Ω and 5 Ω. Then characteristic impedance is: (1) 100 Ω (2) 50 Ω (3) 25 Ω (4) 10 Ω

Method of power factor improvement: a. Use of static capacitor and synchronous condensers b. Use of phase advancers c. Use of induction motors d. Both (a) and (b)

Why are shunt reactors connected at the receiving end of long transmission line system: (1) To increase the terminal voltage (2) To compensate voltage rise caused by capacitive charging at light load (3) To improve power factor (4) None of these

A transmission line to be reciprocal, the condition is (a) A = D (b) AC – BD = 1 (c) AD – BC = 1 (d) AB – CD = 1

Earth wire on EHV overhead transmission line is provided to protect the line against:

If 3000 kW power is to be transmitted over a distance of 30 km, the desirable transmission voltage will be.  (A) 11 kV (B) 33 kV (C) 66 kV (D) 132 kV

Galloping in transmission line conductors arises generally due to - (A) asymmetrical layer of ice formation (B) vortex phenomenon in light winds (C) heavy weight of line conductors (D) adoption of horizontal conductor

For extra high voltage ac transmission lines, conductors used are (a) All aluminium (b) All steel (c) AAAC (d) ACSR

Skin effect is absent in which of the following transmission systems? A) Extra High Voltage (EHV) AC B) High Voltage Direct Current (HVDC) C) Both A and B D) None of these

If the RF transmission is terminated in its Characteristic impedance Z, which of the following statements is wrong : a. The input impedance of transmission line becomes Zc. b. The transmission line acts as an infinite long transmission line. c. The VSWR becomes one d. The VSWR becomes infinite

Which is used for code -in -line model?  A) < script runat="server"> C) Both B) < script javascript="server"> D) None

Which of the following is used extensively where lowest power consumption is necessary?  (1) CMOS (2) NMOS (3) PMOS (4) Any of the above

Stability of a transmission line can be increased by

A transmission line has 1 P.0 impedance on a base of 11 KV, 100 MVA. On a base of 55 KV. it will have a P.0 impedance of

For a transmission line with negligible losses, the lagging reactive power (VAR) delivered at The receiving end, for a given receiving end voltage, is directly proportional to the?