Power Systems MCQs | Part 1 | Diploma in Electrical Engineering

Welcome to 30 MCQs on Power Systems (Part 1) for Diploma in Electrical Engineering. These MCQs are for electrical engineering students. These 30 MCQs will test your knowledge on Power Systems. Each question covers different parts of power systems. Use these questions to prepare for exams.

1. What is the main purpose of a power system network?

A. Energy conversion B. Power generation C. Power distribution D. All of the above

2. Which component is used to step up or step down voltage levels in power systems?

A. Transformer B. Circuit breaker C. Fuse D. Relay

3. What is the unit of electrical power?

A. Volt B. Watt C. Ampere D. Ohm

4. Which type of transformer is used for measurement purposes?

A. Power transformer B. Distribution transformer C. Instrument transformer D. Auto transformer

5. What does the load factor in power systems indicate?

A. Maximum load B. Average load C. Minimum load D. Ratio of average load to maximum load

6. What is the power factor of a purely resistive circuit?

A. 0 B. 1 C. -1 D. 0.5

7. What is the function of a circuit breaker in a power system?

A. Measure current B. Interrupt current flow C. Step up voltage D. Provide insulation

8. What is the main reason for using high voltage for long-distance power transmission?

A. Reduce voltage drop B. Reduce power loss C. Reduce current D. Reduce insulation cost

9. Which type of load causes a lagging power factor?

A. Inductive load B. Capacitive load C. Resistive load D. Reactive load

10. What does the term “reactive power” refer to in a power system?

A. Power consumed by resistive components B. Power stored and released by inductive and capacitive components C. Power dissipated as heat D. Power generated by generators

11. Which device is used to protect electrical circuits from overcurrent?

A. Fuse B. Transformer C. Capacitor D. Inductor

12. What is the formula for calculating electrical power in a DC circuit?

A. \( P = V + I \) B. \( P = V – I \) C. \( P = V \times I \) D. \( P = \frac{V}{I} \)

13. What is the main disadvantage of a high load factor in a power system?

A. Increased power loss B. Decreased efficiency C. Increased wear and tear on equipment D. Increased operational costs

14. What is the primary function of a relay in a power system?

A. Detect faults B. Interrupt power flow C. Step down voltage D. Measure current

15. Which law is used to calculate the magnetic field around a current-carrying conductor?

A. Ohm’s Law B. Ampere’s Law C. Kirchhoff’s Law D. Faraday’s Law

16. What is the main function of a capacitor in a power system?

A. Store magnetic energy B. Store electrical energy C. Convert AC to DC D. Step up voltage

17. What is the primary source of electrical energy in a power plant?

A. Wind B. Solar C. Generator D. Battery

18. What is the role of an inductor in an AC circuit?

A. Store magnetic energy B. Store electrical energy C. Convert AC to DC D. Step up voltage

19. What is the efficiency of a power system?

A. Ratio of input to output power B. Ratio of output to input power C. Difference between input and output power D. Sum of input and output power

20. What is the purpose of using a synchronous condenser in power systems?

A. Increase power factor B. Decrease power factor C. Increase voltage D. Stabilize voltage

21. Which type of fault is most common in a power system?

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

22. What does the term “load shedding” refer to?

A. Increasing power supply B. Reducing power supply C. Balancing power supply D. None of the above

23. What is the primary function of an isolator in a power system?

A. Measure voltage B. Interrupt current flow C. Isolate part of the system for maintenance D. Protect from overvoltage

24. Which method is used for the protection of transmission lines?

A. Differential protection B. Distance protection C. Both A and B D. None of the above

25. What is the typical voltage level of a distribution system?

A. 400 kV B. 11 kV C. 220 kV D. 765 kV

26. What is the main purpose of grounding in electrical systems?

A. Increase voltage B. Safety and protection C. Decrease voltage D. Increase current

27. What is the formula for calculating apparent power in an AC circuit?

A. \( S = V + I \) B. \( S = V – I \) C. \( S = V \times I \) D. \( S = \frac{V}{I} \)

28. Which component is used to store energy in the form of an electric field?

A. Inductor B. Resistor C. Capacitor D. Transformer

29. What does the term “line regulation” refer to in power systems?

A. Variation of output voltage with input voltage B. Variation of input voltage with output voltage C. Variation of current with voltage D. Variation of power with load

30. What is the primary function of a bus bar in a power system?

A. Measure voltage B. Interrupt current flow C. Distribute power D. Protect from overvoltage

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The Bottom Line

Thank you for taking the 30 MCQs on Power Systems (Part 1). They are beneficial for your exam preparation. Review the questions regularly. Stay updated with power system concepts. Keep practicing and learning.

30 MCQs on Power Systems (Part 1) | Diploma in Electrical Engineering