Power Systems – Multiple Choice Questions (MCQs)

1. 61. Which of the following faults is most severe in terms of current magnitude?

   • A. Single line-to-ground fault
   • B. Line-to-line fault
   • C. Double line-to-ground fault
   • D. Three-phase fault

2. 62. What is the function of a series reactor in a power system?

   • A. To limit short-circuit current
   • B. To improve voltage regulation
   • C. To compensate for reactive power
   • D. To absorb harmonics

3. 63. The term 'voltage sag' refers to:

   • A. A temporary decrease in voltage
   • B. A temporary increase in voltage
   • C. A complete loss of voltage
   • D. A long-duration overvoltage

4. 64. Which type of conductor is most commonly used for overhead transmission lines?

   • A. Copper
   • B. Aluminum
   • C. Steel
   • D. Silver

5. 65. What is the main advantage of a ring main distribution system over a radial system?

   • A. Lower initial cost
   • B. Higher reliability
   • C. Simpler fault location
   • D. Less voltage drop

6. 66. The purpose of a power factor corrector is to:

   • A. Increase active power
   • B. Increase reactive power
   • C. Improve system efficiency
   • D. Reduce voltage drop

7. 67. Which of the following is a critical factor in power system stability analysis?

   • A. Load shedding
   • B. Generator inertia
   • C. Relay settings
   • D. Transformer tap settings

8. 68. The term 'critical clearing time' is associated with:

   • A. Steady-state stability
   • B. Transient stability
   • C. Dynamic stability
   • D. Voltage stability

9. 69. What is the primary role of a governor in a hydropower plant?

   • A. To control water flow to the turbine
   • B. To regulate generator excitation
   • C. To control reactive power
   • D. To protect the turbine from overspeed

10. 70. The surge impedance loading (SIL) of a transmission line is independent of:

    • A. Line length
    • B. Operating voltage
    • C. Conductor size
    • D. Characteristic impedance

11. 71. Which of the following is a disadvantage of a nuclear power plant?

    • A. High fuel cost
    • B. High waste disposal cost
    • C. High greenhouse gas emissions
    • D. Intermittent power output

12. 72. The phenomenon of 'voltage collapse' is related to:

    • A. Active power limits
    • B. Reactive power limits
    • C. Frequency stability
    • D. Transient stability