This document is a presentation on power factor correction given by a group of 4 students - Md.Kamruzzaman kousar, Ahmed,S.M. Ishfaq, Talukder,Saiful Islam, and Firoz,A.M.M. The presentation defines power factor, discusses causes of low power factor and the importance of power factor correction. It describes methods of power factor correction using capacitors and lists the advantages of power factor correction such as reduced costs and equipment sizing.

1. RETHWAN FAIZ
Course instructor:

2. WELCOME TO OUR
PRESENTATION………

3. Group no: 7
Group Members
 Md.Kamruzzaman kousar 12-20506-1
 Ahmed,S.M. Ishfaq 13-23626-1
 Talukder,Saiful Islam 13-24165-2
 Firoz,A.M.M 13-24275-2

4. “ Power Factor
Correction “

5. OUTLINE
 DEFINITION
 CAUSES OF LOW POWER FACTOR
 Importance of power factor Correction
 POWER FACTOR CORRECTION
 ADVANTAGES OF POWER FACTOR CORRECTION
 DISADVANTAGES OF LOW POWER FACTOR
 CONCLUSION
 REFERENCES

6. Power factor ↑ =Save money

7. DEFINITION
Power factor (P.F) is the ratio between actual
power to the apparent power.
P.F= Actual power/Apparent power (Kw
/Kva)

8. Power equations

9. power factor
3 type of P.F→
Unity P.F (pure resistive load)
Capacitive load (leading P.F)
Inductive Load (Lagging P.F)

10. Load curves:
 Consumers get :

11. Power factor type
 Unity power factor
 Lagging power factor
(for Inductive load)

12. Power factor type
 Leading power
factor(for capacitive
load)
 Phasor diagram

13. Why is Power Factor Important?
 Consider the following example: A generator
is rated at 600V and supplies one of two
possible loads.
Load 1: P = 120 kW, FP = 1
Load 2: P = 120 kW, FP = 0.6
 How much current (I) is the generator
required to supply in each case?
Load600 V
+
-
I
120 kW

14. 14
DISADVANTAGES OF LOW POWER FACTOR
 Increases heating losses in the transformers and
distribution equipments.
 Reduce plant life.
 Unstabilise voltage levels.
 Increase power losses.
 Upgrade costly equipments.
 Decrease energy efficiency.
 Increase electricity costs by paying power factor
surcharges.

15. Why is Power Factor Important?
 For the load with Fp = 0.6,
the generator had to
supply 133 more amperes
in order to do the same
work (P)!
 Larger current means
larger equipment (wires,
transformers, generators)
which cost more.
 Larger current also means
larger transmission losses
(think I2R).

16. Why is Power Factor Important?
 Because of the wide variation in possible
current requirements due to power factor,
most large electrical equipment is rated using
apparent power (S) in volt-amperes (VA)
instead of real power (P) in watts (W).
 Is it possible to change the power factor of
the load?

17. POWER-FACTOR CORRECTION
FIG. 19.28 Demonstrating the impact of power-factor correction on the power
triangle of a network.

18. Single-phase Supply with Power
Factor Correction
P.F correction circuit Phasor diagram

19. P.F Correction

20. 20
DETERMINING CAPACITOR VALUE
Example
 Power Factor1=74%
 Actual Power=594 kw
 Interested to boost up=97% ,Power Factor2=97%
 Power Factor=KW/KVA
 Cos = kW / kVA
  = Cos-1 (PF1)
  = Cos-1 (74%) =42.27 o

21. 21
 The reactive power was about:
 Tan = kVAr / kW
 kVAr = kW x tan
 kVAr = 594 kW x tan (42.27) = 540 kVAr
 If the power factor were increased to 97%, the reactive power
would be about:
 Cos = kW / kVA
  = Cos-1 (PF2)
  = Cos-1 (97%) = 14.07 o
 kVAr = kW x tan
 kVAr = 594 kW x tan (14.07) = 149 kVAr

22. 22
 Thus, the amount of capacitance required to boost
power factor from 74% to 97% :
 540 kVAr – 149 kVAr = 391 kVAr
 So I recommended 400kvar

23. Power Factor Correction
 Almost all loads are inductive.
 In order to cancel the reactive component of
power, we must add reactance of the opposite
type. This is called power factor correction.
Capacitor bank in
shipboard power panel
for FP correction

24. POWER CAPACITORS
Power Factor correction on site with
Pole Cap
24

25. Power factor correction capacitors for A, B, and C
phases at the Crofton , MD substation
Rating: 230 kV, 360 MVAR
size comparison Capacitor banks

26. 26
ADVANTAGES OF POWER FACTOR CORRECTION
 Eliminate Power Factor Penalties
 Increase System Capacity
 Reduce Line Losses in distribution systems
 Conserve Energy
 Improve voltage stability Increase equipment life
 Save on utility cost
 Enhance equipment operation by improving voltage
 Improve energy efficiency
 Less total plant KVA for the same KW working power
 Improved voltage regulation due to reduced line voltage drop
 Reduction in size of transformers, cables and switchgear in new
installations

27. 27
DISADVANTAGES OF LOW POWER FACTOR
 Increases heating losses in the transformers and
distribution equipments.
 Reduce plant life.
 Unstabilise voltage levels.
 Increase power losses.
 Upgrade costly equipments.
 Decrease energy efficiency.
 Increase electricity costs by paying power factor
surcharges.

28. 28
CONCLUSION
By observing all aspects of the power factor it is clear that
power factor is the most significant part for the utility
Company as well as for the consumer. Utility company rid of
from the power losses while the consumer free from low
power factor penalty charges.
By installing suitably sized power capacitors into the circuit
the Power Factor is improved and the value becomes nearer
to 1 thus minimising line losses and improving the efficiency
of a plant.

29. 29
REFERENCES
 Electrical Power System Design and Analysis
by M.E.EI-Hawary.
 Power System Operations
by Robert H Miller.
 IEEE papers
 www.ABB.com
 BC Hydro (www.bchydro.ca)

30. Have YOU any question?

31. THANK YOU