Power Systems MCQ

Below Power Systems quiz are Multiple Choice Questions (MCQs) type Quiz. These Power Systems MCQ Questions helps you to refresh your Power Systems, you can see the correct option by clicking on it. .
  • 1. Which one of the following statements is NOT true?

    • When the equipment is designed at low power factor it is to be designed for more kVA
    • When power factor is decreased, loss in the cable supplying load is decreased.
    • Due to reduced power factor voltage regulation of line becomes poor 
    • Reduced power factor reduces the efficiency of the plant 
  • 2. The short circuit current of an alternator when short circuited on three phases will be

    • Zero as time goes to infinity
    • Maximum when time goes to infinity
    • Infinity when time goes to infinity
    • Small as time goes to infinity but not zero
  • 3. What is the main source for the formation of wind?

    • Uneven land
    • Sun
    • Vegetation
    • Seasons
  • 4. In which part of the power system has lowest voltage?

    • Generation
    • Distribution
    • Transmission
    • Grid
  • 5. In a star connected system without neutral grounding, zero sequence currents are

    • Zero
    • Phaser sum of phase currents
    • Same as r.m.s. value of phase currents
    • Same as peak value of phase currents
  • 6. The amount of photo generated current increases slightly with increase in _________

    • Temperature
    • Photons
    • Diode current
    • Shunt current
  • 7. The load flow solution is always assured in case of:

    • Newton-Raphson method
    • Gauss method
    • Gauss-Seidel method
    • None of these methods guarantees
  • 8. . One would design the feeders of the transmission system based on its ____________

    • a) current capacity
    • b) voltage drop
    • c) operating voltage
    • d) all of the mentioned
  • 9. While designing the distribution to locality of one lac population with medium dense load requirement, we can employ ___________

    • radial system
    • parallel system
    • ring main system
    • any of the mentioned
  • 10. In India largest thermal power station is located at

    • Kota
    • Sarni
    • Chandrapur
    • Neyveli
  • 11. When a line-to-line fault occurs, the short circuit current of an alternator depends upon its

    • Sub transient reactance
    • Transient reactance
    • Synchronous reactance
    • Short circuit reactance
  • 12. The advantage of neutral earthing is

    • Freedom from persistent arcing grounds
    • Over voltages due to lightning can be discharged to earth
    • Simplified design earth fault protection
    • All of the above
  • 13. Base impedance of the power system is given as:

    • (Base kV)2/Base MVA
    • (Base kV)/Base MVA
    • Base MVA/(Base kV)2
    • None of these
  • 14. Winds having following speed are suitable to operate wind turbines.

    • 5 – 25m/s
    • 10 – 35m/s
    • 20 – 45m/s
    • 30 – 55m/s
  • 15. What is the expression for fault current in line to line fault?

    • If = √3 * (Ea / Z1 + Z2)
    • If = 3 * (Ea / Z1 + Z2)
    • If = √3 * (Ea / Z1 + Z2 + Z0)
    • If = 3 * (Ea / Z1 + Z2 + Z05)
  • 16. The generating voltage and frequency in India is about?

    • 11 kV and 60 Hz
    • 11 kV and 50 Hz
    • 220 kV and 60 Hz
    • 220 kV and 50 Hz
  • 17. What are the terminal conditions in case of SLG fault, if the fault occurs in the phase A?

    • Vb = 0, Ia = 0, Ic = 0
    • Va = 0, Ib = 0, Ic = 0
    • Va = 0, Ia = 0, Ic = 0
    • Vb = 0, Ia = 0, Ib = 0
  • 18. When alternating current passes through a conductor

    • it remains uniformly distributed throughout the section of conductor
    • portion of conductor near the surface carries more current as compared to the core
    • portion of conductor near the surface carries less current as compared to the core
    • entire current passes through the core of the conductor.
  • 19. What are the common assumptions made for the equal area criterion?

    • The transmission line and machine resistances are neglected
    • Rotor speed of the machine is constant
    • Mechanical input remains constant.
    • All of these
  • 20. A _________ distribution system is more reliable than the ______ distribution system.

    • parallel, radial
    • parallel, ring
    • radial, parallel
    • ring, parallel
  • 21. If power factor is less than unity then it will result in

    • Large kVA rating of equipment
    • Greater conductor size
    • Large copper losses
    • All of the above
  • 22. The rated voltage of a 3 phase power system is given by

    • rms peak voltage
    • Peak phase voltage.
    • rms line to line voltage
    • Peak line to line voltage.
  • 23. Which type of system is generally adopted for the generation and transmission of electrical power?

    • 3 phase 4 wire
    • 2 phase 3 wire
    • 3 phase 3 wire
    • None of these
  • 24. The steady state stability of the power system can be improved by

    • Increasing the number of parallel lines between the transmission points
    • Connecting capacitors in series with the line
    • Reducing the excitation of the machines
    • Both a and b
  • 25. The stability of the power system is not affected by which among these?

    • Generator reactance
    • Line losses
    • Excitation of generators
    • All of these
  • 26. Various power system faults in increasing order of severity are

    • LG,LL,LLG,LLLG
    • LLLG,LLG,LG,LL
    • LLG,LLLG,LL,LG
    • LL,LG,LLLG,LLG
  • 27. Which of the following type of reactors are popularly used in power systems?

    • Compensation reactors
    • Current limiting reactors
    • Suppression or Peterson reactors
    • All of these
  • 28. What percentage of fault occurring in the power system is line to line fault

    • 5 %
    • 30 %
    • 25 %
    • 15 %