Power Factor Improvement and Load Management — MCQs – EE

1. The power factor of an electrical system is defined as the ratio of:
(A) Real power to apparent power
(B) Apparent power to real power
(C) Reactive power to apparent power
(D) Reactive power to real power

2. The ideal power factor for maximum efficiency in an electrical system is:
(A) 1.0 (unity)
(B) 0.5 lagging
(C) 0.8 lagging
(D) 0.9 leading

3. A low power factor indicates:
(A) High reactive power in the system
(B) Purely resistive load
(C) High system efficiency
(D) Balanced load conditions

4. The main cause of low power factor in industries is:
(A) Inductive loads such as motors and transformers
(B) Purely resistive loads
(C) Lighting loads
(D) DC machines

5. Power factor improvement primarily results in:
(A) Reduced line losses and better voltage regulation
(B) Increased reactive current
(C) Higher energy consumption
(D) Poor system stability

6. The most commonly used equipment for power factor correction is:
(A) Capacitor bank
(B) Inductor
(C) Transformer
(D) Alternator

7. Capacitors improve power factor by:
(A) Providing leading reactive power
(B) Consuming more real power
(C) Increasing lagging current
(D) Reducing load current magnitude

8. The installation of capacitor banks at distribution substations helps in:
(A) Reducing transmission losses
(B) Increasing power factor lag
(C) Lowering voltage
(D) Increasing load current

9. The use of synchronous condensers helps in:
(A) Power factor correction dynamically
(B) Reducing active power
(C) Increasing frequency
(D) Changing power direction

10. In a balanced three-phase system, power factor is calculated using:
(A) Cosine of the phase angle between voltage and current
(B) Tangent of the phase angle
(C) Sine of the phase angle
(D) Reciprocal of impedance

11. The automatic power factor controller (APFC) panel:
(A) Switches capacitor banks automatically based on load power factor
(B) Measures voltage only
(C) Works only during no-load condition
(D) Disconnects loads manually

12. A power factor of 0.7 lagging indicates:
(A) Large inductive load present
(B) Balanced resistive load
(C) Over-corrected system
(D) Purely capacitive circuit

13. Improving power factor leads to which of the following benefits?
(A) Reduction in kVA demand and energy cost
(B) Increased transmission losses
(C) Higher penalty charges
(D) Overvoltage conditions always

14. Power utilities often penalize consumers for:
(A) Maintaining low power factor
(B) Operating at unity power factor
(C) Reducing reactive power
(D) Using capacitor banks

15. One of the main advantages of power factor improvement is:
(A) Increased system capacity
(B) Increased copper losses
(C) Reduced load factor
(D) Decreased power availability

16. Load management refers to:
(A) Controlling and optimizing the use of electrical loads
(B) Increasing load at all times
(C) Switching off all loads simultaneously
(D) Overloading the network intentionally

17. The main objective of load management is to:
(A) Reduce peak demand and improve system reliability
(B) Increase demand continuously
(C) Reduce diversity factor
(D) Overload transmission lines

18. Demand Side Management (DSM) includes:
(A) Techniques to influence energy usage patterns by consumers
(B) Generator maintenance programs
(C) Transformer cooling design
(D) Substation layout

19. Load shifting is a type of:
(A) Load management strategy
(B) Power loss calculation
(C) Circuit fault
(D) Harmonic compensation

20. Load shifting aims to:
(A) Move non-essential loads to off-peak hours
(B) Increase on-peak demand
(C) Decrease off-peak utilization
(D) Maintain constant load always

21. Peak clipping is a load management technique that:
(A) Reduces peak demand using control systems
(B) Increases base load
(C) Eliminates energy audits
(D) Shifts loads to peak hours

22. Time-of-day (ToD) tariff is used for:
(A) Encouraging consumers to use electricity during off-peak hours
(B) Maintaining constant rates throughout the day
(C) Penalizing low voltage levels
(D) Improving insulation resistance

23. An improved power factor results in:
(A) Lower current for the same load power
(B) Higher line losses
(C) Poor voltage regulation
(D) Increased reactive power

24. Reactive power compensation helps to:
(A) Maintain voltage profile and improve stability
(B) Increase copper losses
(C) Reduce system frequency
(D) Increase harmonics

25. In industrial systems, automatic capacitor control is preferred because it:
(A) Responds quickly to load variations
(B) Requires manual supervision
(C) Operates continuously at full capacity
(D) Increases system lagging

26. Load management is crucial for utilities because it:
(A) Avoids system overloading and reduces generation cost
(B) Increases energy theft
(C) Reduces reliability
(D) Overloads transformers

27. A consumer with poor power factor will experience:
(A) Higher demand charges
(B) Lower losses
(C) Reduced apparent power
(D) Lower current

28. Power factor correction devices should be installed:
(A) Close to inductive loads
(B) Near the generator
(C) Only at the main supply
(D) Away from load centers

29. Load factor improvement helps in:
(A) Reducing generation capacity requirements
(B) Increasing peak load
(C) Reducing load diversity
(D) Increasing energy tariffs

30. The combined effect of power factor improvement and load management leads to:
(A) Energy savings, reduced costs, and improved system reliability
(B) Increased power losses
(C) Lower voltage levels
(D) Reduced system stability