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