Transmission Lines: Power Transmission and Distribution

Question 1

Which line parameter is used to calculate the voltage drop of a transmission line?

Accepted Answer

Resistance

Answer

Inductance

Answer

Capacitance

Answer

Conductance

Question 2

What is the main function of overhead ground wires (OHGW) in transmission lines?

Accepted Answer

Provide lightning protection

Answer

Reduce voltage drop

Answer

Improve stability

Answer

Increase current-carrying capacity

Question 3

What is the Ferranti effect in transmission lines?

Accepted Answer

Increase in voltage at the receiving end with increasing line length

Answer

Decrease in current at the receiving end with decreasing line length

Answer

Increase in power loss with decreasing line length

Answer

Decrease in voltage at the sending end with increasing line length

Question 4

Which of these factors has no effect on the efficiency of power transmission in a transmission line?

Accepted Answer

Voltage of the transmitted power

Answer

Conductor material

Answer

Line length

Question 5

Identify the most commonly used transmission line type for long-distance, high-voltage power transmission.

Accepted Answer

Overhead transmission line

Answer

Underground cable transmission line

Answer

Submarine cable transmission line

Answer

Busbar transmission line

Question 6

Which transmission line parameter directly influences its resistance?

Accepted Answer

Conductor cross-sectional area

Answer

Line length

Answer

Conductor material

Answer

Insulation thickness

Question 7

Explain the primary purpose of utilizing bundled conductors in a transmission line.

Accepted Answer

To increase the current-carrying capacity

Answer

To reduce line inductance

Answer

To reduce line capacitance

Answer

To improve voltage regulation

Question 8

For determining the steady-state operating conditions of a power system, which type of power flow analysis is employed?

Accepted Answer

Load flow analysis

Answer

Short circuit analysis

Answer

Transient stability analysis

Answer

Harmonic analysis

Question 9

What is the predominant contributor to power loss in transmission lines?

Accepted Answer

Conductor resistance

Answer

Inductance

Answer

Capacitance

Answer

Insulation leakage

Question 10

What is the primary function of insulators in a transmission line?

Accepted Answer

To prevent short circuits between conductors

Answer

To provide mechanical support to the conductors

Answer

To absorb lightning strikes

Answer

To reduce line losses

Question 11

In areas with high winds, which type of tower is commonly utilized to support transmission lines?

Accepted Answer

Guyed tower

Answer

Lattice tower

Answer

Monopole tower

Answer

Self-supporting tower

Question 12

What is the main purpose of utilizing corona rings on transmission lines?

Accepted Answer

To suppress corona discharge

Answer

To reduce line losses

Answer

To enhance voltage regulation

Answer

To protect insulators from damage

Question 13

Which of the following is NOT a type of transmission line?

Accepted Answer

Coaxial cable

Answer

Overhead line

Answer

Underground cable

Answer

Bundled phase conductors

Question 14

What is the primary parameter used to characterize the electrical properties of a transmission line?

Accepted Answer

Impedance

Answer

Resistance

Answer

Inductance

Answer

Capacitance

Question 15

Which of the following factors increases the power loss in a transmission line?

Accepted Answer

Higher current

Answer

Higher voltage

Answer

Shorter length

Answer

Lower frequency

Question 16

What is the purpose of using bundled phase conductors in transmission lines?

Accepted Answer

Increase current-carrying capacity

Answer

Reduce corona loss

Answer

Improve voltage stability

Answer

Enhance insulation

Question 17

What is the main advantage of using underground transmission lines compared to overhead lines?

Accepted Answer

Reduced visual impact

Answer

Improved reliability

Answer

Lower maintenance costs

Answer

Higher power transmission capacity

Question 18

What is the purpose of using corona rings on transmission lines?

Accepted Answer

Reduce corona loss

Answer

Increase voltage insulation

Answer

Improve current flow

Answer

Enhance mechanical stability

Question 19

Which of the following is NOT an environmental concern associated with overhead transmission lines?

Accepted Answer

Enhancement of property values

Answer

Visual impact on the landscape

Answer

Production of electromagnetic fields

Answer

Increased risk of wildfires

Question 20

Which transmission tower type is ideal for urban areas due to its compact design?

Accepted Answer

Monopole Tower

Answer

Suspension Tower

Answer

Guyed Tower

Question 21

What is the primary purpose of a transmission line?

Accepted Answer

To carry electricity over long distances

Answer

To create electricity

Answer

To alter voltage levels

Answer

To manage the flow of electricity

Question 22

Which term describes the voltage of a transmission line relative to the ground?

Accepted Answer

Line voltage

Answer

Phase voltage

Answer

Ground voltage

Answer

Neutral voltage

Question 23

Which material is most frequently used for conductors in overhead transmission lines?

Accepted Answer

Aluminum

Answer

Copper

Answer

Iron

Answer

Gold

Question 24

What is the term for energy losses that occur on a transmission line?

Accepted Answer

Line losses

Answer

System losses

Answer

Power losses

Answer

Voltage losses

Question 25

What is a primary cause of corona discharge on transmission lines?

Accepted Answer

High humidity

Answer

Low voltage

Answer

Low resistance

Answer

Clean insulators

Question 26

What is the purpose of protective relays in transmission lines?

Accepted Answer

To isolate faulty sections of a line

Answer

To prevent faults from spreading

Answer

To regulate voltage levels

Answer

To control power flow

Question 27

Which effect describes the scenario where the voltage at the receiving end of a transmission line exceeds the voltage at the sending end, especially under light or no-load conditions?

Accepted Answer

Ferranti effect

Answer

Skin effect

Answer

Corona discharge

Answer

Proximity effect

Question 28

Which of the following is NOT a type of transmission line installation?

Accepted Answer

Submersible

Answer

Overhead

Answer

Underground

Answer

Submarine

Question 29

Which of the following measures is NOT used to protect transmission lines from lightning strikes and electrical faults?

Accepted Answer

Inductive coupling

Answer

Surge arresters

Answer

Insulators

Answer

Ground wires

Question 30

Define surge impedance loading and explain its impact on the efficiency and stability of power transmission systems.

Accepted Answer

Surge impedance loading is a condition where the transmission line's characteristic impedance matches the load impedance, maximizing power transfer and minimizing losses.

Answer

Surge impedance loading occurs when a sudden voltage increase causes a corresponding current increase.

Answer

Surge impedance loading focuses on maintaining voltage stability within acceptable limits.

Answer

Surge impedance loading has no significant impact on transmission system efficiency or stability.

Question 31

Which of the following is a common configuration for overhead transmission lines?

Accepted Answer

Horizontal

Answer

Diagonal

Answer

Vertical

Answer

Curved

Question 32

What is the primary parameter of a transmission line that affects voltage drop?

Accepted Answer

Resistance

Answer

Capacitance

Answer

Inductance

Question 33

Which of the following power flow equations represents the apparent power flow in a transmission line?

Accepted Answer

S = P + jQ

Answer

P = VIcos(θ)

Answer

P = VIsin(θ)

Answer

Q = VIcos(θ)

Question 34

What is a significant environmental impact associated with overhead transmission lines?

Accepted Answer

Land use and aesthetic concerns

Answer

Noise pollution

Answer

Water pollution

Answer

Greenhouse gas emissions

Question 35

What is the primary role of a transformer in a transmission system?

Accepted Answer

To change voltage levels

Answer

To isolate circuits

Answer

To protect against overloads

Answer

To reduce current flow

Question 36

What is the purpose of using surge arresters in transmission lines?

Accepted Answer

To protect against voltage surges

Answer

To increase insulation

Answer

To improve power flow

Answer

To reduce corona

Question 37

Which transmission line parameter primarily governs its current-carrying capacity?

Accepted Answer

Conductor size and material

Answer

Tower spacing

Answer

Insulator type

Answer

Line length

Question 38

Which formula is used to calculate the active power flow in a transmission line?

Accepted Answer

P = VI cos(θ)

Answer

P = V²/R

Answer

P = I²/R

Answer

P = IV

Question 39

What is the primary cause of energy loss in transmission lines?

Accepted Answer

Conductor resistance

Answer

Inductance

Answer

Capacitance

Answer

Proximity effect

Question 40

Which type of conductor arrangement minimizes inductance and enhances efficiency?

Accepted Answer

Bundle conductor

Answer

Quadruple conductor

Answer

Twin conductor

Answer

Single conductor

Question 41

What is the primary purpose of corona rings on transmission lines?

Accepted Answer

Reduce corona discharge and energy loss

Answer

Increase conductor current capacity

Answer

Improve insulation strength

Answer

Enhance mechanical strength

Question 42

Which fault type results in the most severe fault current?

Accepted Answer

Three-phase fault

Answer

Double-phase-to-ground fault

Answer

Phase-to-phase fault

Answer

Single-phase-to-ground fault

Question 43

What is the primary function of a substation in a transmission system?

Accepted Answer

Voltage transformation and interconnection of transmission lines

Answer

Distribution of power to consumers

Answer

Generation of electrical power

Question 44

What factor primarily determines the surge impedance of a transmission line?

Accepted Answer

Conductor inductance and insulation capacitance

Answer

Insulation resistance and capacitance

Answer

Conductor size and tower spacing

Answer

Conductor resistance and inductance

Question 45

Which type of transmission line operates at voltages typically below 100 kV?

Accepted Answer

Distribution line

Answer

Sub-transmission line

Answer

Transmission line

Answer

Extra-high voltage (EHV) line

Question 46

What parameter is primarily used to characterize transmission line impedance?

Accepted Answer

Inductance

Answer

Capacitance

Answer

Conductance

Answer

Resistance

Question 47

What element of a transmission line has the greatest impact on its power loss?

Accepted Answer

Resistance

Answer

Inductance

Answer

Capacitance

Question 48

What is a key advantage of overhead transmission lines compared to underground transmission lines?

Accepted Answer

Lower cost of construction and maintenance

Answer

Higher energy efficiency

Answer

Improved reliability

Answer

Reduced environmental impact

Question 49

Which device is primarily used to protect transmission lines from short-circuit faults?

Accepted Answer

Circuit breaker

Answer

Fuse

Answer

Lightning arrester

Answer

Recloser

Question 50

What is the formula for calculating the inductance of a single-phase transmission line with conductor spacing 'D' and conductor radius 'r'?

Accepted Answer

L = 0.5 * μ0 * ln(D/r)

Answer

L = μ0 * (D + r)

Answer

L = μ0 * π * r

Answer

L = 0.5 * μ0 * (D - r)

Question 51

Which factors determine the surge impedance of a transmission line?

Accepted Answer

Inductance and capacitance

Answer

Inductance and conductance

Answer

Resistance and inductance

Answer

Capacitance and resistance

Question 52

What is the typical voltage range used for high-voltage transmission lines?

Accepted Answer

115 kV to 1,000 kV

Answer

230 kV to 400 kV

Answer

1 kV to 10 kV

Answer

10 kV to 69 kV