Automatic power factor correction presentation. Project presentation for final year B.Tech or B.E course. APFC

1. PROJECT PRESENTATION ON
AUTOMATIC POWER FACTOR
CORRECTION
GUIDED BY:-
Dr. BARUN MONDAL, Asst. prof.
EE Department
Presented By:-
DEPARTMENT OF ELECTRICAL ENGINEERING
Kalyani Govt. Engineering College
1. Atanu Chakraborty (10201615057)
2. Kartick Manna (10201615060)
3. Koushik Garai (10201615061)
4. Santu Sutradhar (10201615071)

2. CONTENTS:
 Introduction
 Block diagram
 Detailed Block diagram
 Working principle
 Power supply circuit
 Power factor measurement circuit
 Circuit Diagram of ZCD
 XOR Gate Generates Pulse
 Micro Controller
 LCD
 Relay
 Capacitor Bank
 Advantage
 Disadvantage
 Applications
 Conclusion

3. INTRODUCTION:
 This project report represents one of the most effective automatic
power factor improvements.
 Static capacitors which will be controlled by a Microcontroller
with very low cost.
 Power factor is set as standard value into the microcontroller IC.
 Potential Transformer and Current Transformer are used for pf
measurement
 Here one of the most popular Microcontroller is used i.e. Arduino
ATmega328

4. Source
230VAC
POWER
FACTOR
MEASURMENT
CIRCUIT
LCD Display
Micro controller
RelayCapacitor BankLOAD
Power Supply
230V AC - 5V DC
communication
BLOCK DIAGRAM

5. Circuit Diagram

6. Working Principle:
 Power supply is given to the circuit.
 Power factor is set as standard value into the microcontroller
IC.
 In case of deviations , microcontroller activates relay.
 Relay senses and connects the capacitor.
 The capacitor is connected parallel across the load by relay
without any hazard.
 The APFC unit controls PF by activating/deactivating
capacitors.

7. Power Supply Circuit
 Step-down
Transformer
 Diode
Rectifier
 Filtering
Capacitor
 Voltage
Regulator

8. POWER FACTOR MEARSURMENT CIRCUIT
Potential
Transformer Current Transformer Zero Crossing Detector

9. Circuit Diagram of ZCD

10. XOR gate generates pulse
Φ=(t/T)*360

11. MICRO COTROLLER:
A Microcontroller Contains:
 The processor (The CPU),
 Program memory,
 Memory for input and output(RAM),
 A clock and an I/O control unit.
 Microcontroller it is an electronic clock driven
reprogrammable device which can take some
digital data , process the data and gives us to
required output data.

12. Features of the ATmega328

13. Algorithm of Microcontroller
Read Voltage and
Current
Calculate
PF
PF<PFmin?
PF>Pfmax?
Switch on one
capacitor
Switch off one
capacitor
Yes
Yes
No
No

14. LCD:
 A liquid crystal display (LCD) is a flat paneldisplay
 It uses the light modulating properties of liquid
crystals (LCs).
 LCDsApplications:
 Computer monitors,
 Television,
 Instrument panels,signage, etc.
 LCDs have replaced cathode ray tube (CRT) displays in
most applications.

15. RELAY:

16. WORKING OF RELAY:
 A relay is an electrically operated
switch.
 The coil current can be on or off so
relays have two switch positions and
they are double throw (changeover)
switches.
 Relays allow one circuit to switch a
second circuit which can
be completely separate from the first.
 It is also known as a sensing device.

17. Capacitor Bank
A capacitor bank is a group of several capacitors of the
same rating that are connected in series or parallel with
each other to store electrical energy .
The resulting bank is then used to counteract(resist) or
correct a power factor lag or phase shift in an
alternative current (AC) power supply. They can also be
used in a direct current (DC) power supply to increase
the ripple current capacity of the power supply or to
increase the overall amount of stored energy.
Capacitor banks are generally used in substations. Since
most of the household and industrial appliances are
either resistive(eg. incandescent light, heater, etc.) or
inductive(e.g. refrigerator, air-conditioner, motor, etc).
The capacitive load of the capacitor bank will help to
adjust the power factor as close to 1 as possible, in
which case the voltage and current are in phase and
deliver maximum usable power to the load.

18. Advantage

19. Disadvantage
They have short service life.
They are easily damaged if the voltage
exceeds the rated value
Once the capacitor is damaged, their repair
is uneconomical.

20. Applications:
 To improve power factor of inductive load such as
Induction Motors
A high power factor is generally desirable in a
transmission system to reduce
transmission losses and improve voltage.
It provides good voltage regulation and can be used
at substation

21. CONCLUSIONS
 This paper shows an efficient technique to improve the power factor of a
power system by an economical way.
 Static capacitors are invariably used for power factor improvement in factories
or distribution line. But this paper presents a system that uses capacitors only
when power factor is low otherwise they are cut off from line. Thus it not only
improves the power factor but also increases the life time of static capacitors.
 For high rating load this capacitor method may be insufficient and we can use
Synchronous machine for that. We can control the excitation of the
synchronous machine in order to control power factor of the load

22. References
We get the idea from the following sources
1. www.google.com
2.www.wikipedia.org
3.Global Journal of Researches in Engineering
Electrical and Electronics Engineering
4.International Journal of Engineering and Innovative Technology
(IJEIT)
Volume 3, Issue 4, October 2013
5.https://electricalnotes.wordpress.com/2011/03/20/automaticpower-factor-
correction/
6.http://microcontrollerslab.com/automatic-power-factor-controllerusing-pic-
microcontroller/
7. http://www.edgefxkits.com/minimizing-penalty-in-industrialpower-consumption-by-
engaging-apfc-unit