AUTOMATIC THREE PHASE SUPPLY CHANGOVER

AUTOMATIC THREE PHASE SUPPLY CHANGOVER

1. AUTOMATIC THREE PHASE SUPPLY CHANGEROVER SUBMITTED BY: Manish Kumar (1473720019) Rohit Jaiswal (1473720029) Setu Parmar (1473720034) Shubham Rao (1473720038) RAJKIYA ENGINEERING COLLEGE, AMBEDKARNAGAR GUIDED BY: Mr. Mayank Kr. Gautam Department Of Electrical Engineering

2. CONTENTS Introduction Types Of Electric Power Supply Block diagram Components Used Applications Advantages Future Scope Description Of Project References

3. INTRODUCTION Automatic feature - need of the day. In case of the electrical appliance control using automation ensures more safety. Automation becomes necessary as the rate of power outage in developing countries becomes predominantly high. If processes of change-over are manual, human error may occur; leading to machine damage, electrocution, increased down time consequently introducing massive losses. However, if the starting of the generator is automatic, switching battery voltage to ignition coil of the generator while the main power relay switches the load, the down time would be reduced.

4. TYPES OF ELECTRIC POWER SUPPLY All the possible types of electric supplies are listed below : Single - phase two wire supply Two - phase three wire supply Three - phase four wire supply Backup generator Uninterruptible power source (battery flywheel backup ( Solar power

5. In our project, we can connect three types of sources simultaneously and we can also set priorities to those sources. If the first priority source is down then it will automatically switch to the source which is at priority number 2 without any delay . If both the sources which are at priority numbers 1 & 2 are missing, then it will switch to third source without any delay . In this way, we can assure an uninterrupted power supply . We will face black out only if all the three sources are missing . DESCRIPTION OF PROJECT

6. BLOCK DIAGRAM

7. COMPONENTS These are the following components that are used Power Supply Three voltage Comparators (LM741 AH1883) 3-input-AND gate (4073) Two BC 108 transistors Two12V ; 30mA relays Biasing resistors 240/12V; 500mA transformer Bridge rectifier (1N4002) Two voltage regulators (LM7812 and LM7805) Variac Multimeter & some other components.

8. TRANSFORMER Transformer is a static electrical device that transfers by inductive coupling between its winding circuit. Here in this model we are using step down transformer.

9. BRIDGE RECTIFIER A diode bridge is an arrangement of four diodes in a bridge circuit configuration that provides the same polarity of output for either polarity of input. When used in its most common application, for conversion of an alternating current(ac) input into a direct current(dc) output,it is known as bridge rectifier.

10. RELAY Relays are electromechanical switches. Relays have two circuit namely load circuit and control circuit. The control circuit has a small coil whereas the load circuit has a switch. The coil controls the operation of switch.

11. VOLTAGE REGULATOR A voltage regulator is designed to automatically maintain a constant voltage level. A voltage regulator may use a simple feed-forward design or may include negative feedback. It may use an electromechanical mechanism, or electronic components. 78 Series regulator

12. IC 7806 It is a voltage regulator meant to give regulated 6V supply when provided with suitable input. The 78xx (sometimes LM78xx) is a family of self-contained fixed linear voltage regulator integrated circuit. The 78xx family is commonly used in electronic circuits requiring a regulated power supply due to their ease-of-use and low cost. For ICs within the family, the  xx  is replaced with two digits, indicating the output voltage (for example, the 7805 has a 5 volt output, while the 7812 produces 12 volts).

13. A miniature snap-action switch, also trademarked and frequently known as a micro switch. It is an electric switch that is actuated by very little physical force, through the use of a tipping down mechanism, sometimes called an "over- center " mechanism. Switching happens reliably at specific and repeatable positions of the actuator, which is not necessarily true of other mechanisms. MICRO SWITCHES

14. Change-Over/Electrical Relay Isolation Stage Physical size and pin arrangement: A relay is chose based on the existing PCB to ensure that its dimensions and pin arrangement are suitable for the designed project. Coil Voltage: The relay coil voltage rating and resistance were taken into consideration. Coil Resistance: The circuit must be able to supply the current required by the relay coil. From Ohm’s law,  

15. After the construction of the automatic voltage change-over system, a variac was used to carry out the measurement and the results. CHANGEOVER SWITCH

16. APPLICATIONS This project is very useful. It removes the need of human effort to change the phase whenever the power supply went out of phase. Hospital Multiple building. Lifts Domestic supply School and college continuity power supply Call centres Hotels Cinema Big electric farness Computer based seismography

17. ADVANTAGES Continuity power supply. Cost is very less. Less voltage drop compare to inverter. Energy efficient. Low voltage protection. Over load protection. Less maintenance compare to inverter. Less space. Give good efficiency of motor Give suitable load

18. FUTURE SCOPE The project have huge future scope because every home is facing the problem of current gone in the phase and need to put wire from one phase to the next phase. Sometimes electric shock also takes place because of this problem. Everyone wants this phase changing process automatic. So we can say that the project have huge future scope.

19. [1]. American Journal of Engineering Research (AJER) Paper. [2]. G. Mazur and G. Rocks, Electrical Motor Controls (American Technical Publisher, New York, NY USA,2001). [3]. P. Horowitz and H. Winfield, The Art of Electronics (2 nd edition. Cambridge Univ. Press, Cambridge, UK, 1989). [4]. P. Horowitz and H. Winfield, The Art of Electronics (2nd edition. Cambridge Univ. Press, Cambridge, UK, 1989). [5]. Theraja , B. L and Theraja , A.K, “Electrical Technology (5thedition, S Chand New Delhi, India, 2005). REFERENCES

20. THANK YOU