Transmission and Distribution Systems MCQs (Part-12)

What is the main purpose of high-voltage transmission lines?

A To reduce power factor
B To minimize power losses during long-distance power transfer
C To increase line capacitance
D To regulate system frequency

Which system is primarily used for local distribution of electricity?

A High-voltage transmission system
B Medium-voltage system
C Low-voltage distribution system
D Grid interconnection system

What material is commonly used for overhead line conductors?

A Iron
B Steel
C Aluminum
D Silver

What is the purpose of an insulator in a power system?

A To support the conductor and prevent leakage currents
B To increase voltage
C To regulate current
D To increase inductance

What is the primary role of a step-up transformer?

A To increase the frequency
B To reduce transmission losses by increasing voltage
C To balance load
D To stabilize current

Which phenomenon leads to ionization of air around high-voltage conductors?

A Corona discharge
B Ferranti effect
C Dielectric breakdown
D Eddy current loss

What is the primary purpose of a substation in a power system?

A To generate electricity
B To step up or step down voltage levels
C To store energy
D To improve conductor efficiency

What is the role of capacitance in long transmission lines?

A Increases power losses
B Causes a rise in voltage at the receiving end under light loads (Ferranti effect)
C Reduces inductance
D Reduces line resistance

What is the primary function of a lightning arrester in a power system?

A To step up voltage levels
B To protect the system from overvoltage due to lightning strikes
C To regulate power factor
D To reduce transmission losses

What is the purpose of a circuit breaker in a power system?

A To step down voltage levels
B To isolate faulty sections of the system during faults
C To regulate current
D To increase line impedance

What is the primary role of grounding in a power system?

A To increase voltage
B To provide safety by dissipating fault currents into the ground
C To balance load
D To reduce inductance

What is the main advantage of integrating renewable energy into the power grid?

A Increased transmission losses
B Sustainable and environmentally friendly energy supply
C Increased complexity of the grid
D Higher system frequency

What is the role of a smart meter in a power system?

A To step up voltage
B To monitor and record energy usage in real-time
C To balance load across phases
D To reduce line impedance

What is the main purpose of reactive power in a power system?

A To perform useful work
B To support voltage levels and maintain system stability
C To reduce power losses
D To increase current flow

What is the effect of line inductance on the transmission system?

A It increases line resistance
B It opposes changes in current and contributes to voltage regulation
C It reduces voltage levels
D It increases capacitance

What is the primary function of a capacitor bank in a power system?

A To supply active power
B To provide reactive power and improve power factor
C To increase voltage levels
D To reduce current

What is the effect of capacitance in long transmission lines under light load conditions?

A Causes a decrease in voltage at the receiving end
B Causes a voltage rise at the receiving end (Ferranti effect)
C Reduces line impedance
D Increases line resistance

What is the function of a relay in a power system protection scheme?

A To measure power flow
B To detect abnormal conditions and trigger protection devices
C To store energy for future use
D To increase line impedance

What is the primary function of a microgrid?

A To increase line resistance
B To provide localized power supply and integrate renewable energy
C To step up voltage levels
D To reduce line capacitance

What is the primary advantage of using smart meters in a distribution system?

A To increase line inductance
B To provide real-time data for better energy management and billing
C To balance the load across phases
D To reduce power factor