power factor and its improvement

2. POWER FACTOR IMPROVEMENT
Group Members: Instructor:
Shoaib Shaikh(G.L.) K-F16EL-19 Dr. Mazhar Hussain
Razzak Shaikh K-F16EL-49
Abdul Sami K-F16EL-43
Saddam Wassan K-F16EL-62

3. CONTENTS
• POWER & ITS TYPES
• POWER FACTOR
• CAUSES OF LOW POWER FACTOR
• EFFECTS OF LOW POWER FACTOR
• POWER FACTOR IMPROVEMENT
• BENEFITS OF POWER FACTOR IMPROVEMENT
• CONCLUSION

4. POWER & ITS TYPES
POWER
Electrical Power is the rate at which electric energy is transferred by an
electrical circuit.
TYPES OF POWER
• Active Power:-
The power which is actually consumed or utilized in an AC circuit is called
True power or Active Power or Real power. It is measured in kilo watt (kW).
• Reactive Power:-
The power which flows back and froth that mean it moves in both the direction
in the circuit or react upon itself, is called Reactive Power. The reactive power
is measured in kilo volt ampere reactive (kVAR)
• Apparent Power:-
It is simply the combination of voltage and current present in a circuit. It is
measured in kilo volt ampere (kVA).

5. POWER FACTOR
Power factor is the measure of how effectively
electrical equipment converts electric power
(supplied by your power utility) into useful
power output.
In technical terms, it is the ratio of Active Power
(kW) to the Apparent Power (kVA) of an
electrical installation.
P.F. = kW / kVA

6. Beer Mug Analogy
 Looking at our beer mug
analogy above, power factor
would be the ratio of beer (kW)
to beer plus foam (kVA).
P.F. = kW / kW + kVAR
P.F. = Beer / Beer + Foam

7. CAUSES OF LOW POWER FACTOR
 Inductive Loads
Low power factor results when active power(kW)
is small in relation to apparent power(kVAR).
Inductive loads (which are sources of Reactive Power)
causes a large kVAR in a system, which includes:
• Transformers
• Induction motors
• Induction generators (wind mill generators)

8.  Varying Load in Power System
As we know that load on power system varies.
During low load period, supply voltage is increased
which increase the magnetizing current which cause the
decreased power factor.
 Due to the loads like Industrial heating furnace,
Electrical discharge lamps (High intensity discharge
lighting) Arc lamps; these loads operate a very low
power factor.

9. EFFECTS OF LOW POWER FACTOR
 Effect on Transmission line (Greater conductor size)
 Large KVA ratings are produced in electrical
machinery, i.e. Generators, Transformers
 High losses in power system
 High voltage drops (poor voltage regulation)
 Reduced handling capacity of system

10. POWER FACTOR IMPROVEMENT
The power factor correction means bringing
the power factor of an AC circuit nearer to one
by using the equipment which absorbs or supply
the reactive power to the circuit.
 The power factor correction will not
change the amount of true power, but it
will reduce the apparent power and the
total current drawn from the load.

11. METHODS FOR POWER FACTOR
IMPROVEMENT

12.  By Capacitors:
Improving power factor means reducing the
phase difference between voltage and current. Since
majority of loads are of inductive nature, they
require some amount of reactive power for them to
function. This reactive power is provided by the
capacitor or bank of capacitors installed parallel to
the load. They act as a source of local reactive power
and thus less reactive power flows through the line.
Basically they reduces the phase difference between
the voltage and current.

13.  By Synchronous Condenser:
They are 3 phase synchronous motor with no
load attached to its shaft. The synchronous motor
has the characteristics of operating under any power
factor leading, lagging or unity depending upon the
excitation. For inductive loads, synchronous
condenser is connected towards load side and is
overexcited. This makes it behave like a capacitor. It
draws the lagging current from the supply or
supplies the reactive power.

14.  By Phase Advancer:
This is an ac exciter mainly used to improve
power factor of induction motor. They are
mounted on shaft of the motor and is connected
in the rotor circuit of the motor. It improves the
power factor by providing the exciting ampere
turns to produce required flux at slip frequency.
Further if ampere turns are increased, it can be
made to operate at leading power factor.

15. BENEFITS OF IMPROVED POWER FACTOR
 Lower utility fees by
a. Reducing peak KW billing demand
b. Eliminating the power factor penalty
 Increased system capacity
 Reduced system losses in your electrical system
 Increased voltage stability
 Enhance equipment operation(more efficient
motors)

16. 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 on electrical side. Utility company
gets rid of from the power losses while the
consumer free from low power factor penalty
charges.