DESIGN AND CONTRUCTION OF UNINTERRUPTED POWER SUPLY
BACKGROUND OF STUDY
Major use of electricity today arises in device using electrical current at either low or zero frequency. Thus an uninterruptible power supply is a devise that provide emergency power to the load immediately when the input or main source supply power fails. The uninterruptible power supply (UPS) is a combination of the inverter, the mosfet drive, transformer, battery and an automatic change over switch. It provide near instantaneous protection from input power interruption by giving-out energy store in the battery. The disturbance may come up as a result of short circuit leading to transient and sudden isolation in the commercial power supply. The uninterruptible power supply is the best solution to power conditioning on critical load such as air route traffic, real time data processing computer, industrial control processing system etc, because of their sensitivity to the nature of the power supply for operations. Protection of this kind of equipments is very necessary.
Looking at our country today we are plagued with constant power failure and even lack of power to some rural and urban center, hence there is a need to have a system which convert a readily available direct current(DC) to an alternating current(AC) with higher efficiency and low maintenance cost like the uninterruptable power supply (UPS).
- PROJECT OBJECTIVE AND AIM
The purpose of the project is to design and construct a circuit that will take care of
a 220v,5KVA uninterruptable power supply.
The specific objectives of this study are as follows
- To have a source of generating that has no negative effect on the environment (i.e. no green house effect).
- To understand basically the various component require assembling a 220v, 5KVA uninterruptable power supply (UPS).
- To understand the working principle of the 220v, 5KVA uninterruptable power supply.
- To produce a 22ov, 5KVA (UPS) for large business environment
I was motivated by the need to generate an electrical power through a noiseless, portable and inexpensive source that has no negative effect on the environment. I also look up the challenge to carry-out this project because of my quest to no more about power generation.
1.3 SCOPE OF THE PROJECT
The scope of this project is to design and construct an uninterrupted power supply (UPS) with an output power rating of 5KVA,maximum output current rating of 20.83A, output of 220vac from a 24dc input.
1.4 PROJCET JUSTIFICATION
The design and construction of 220v, 5kva uninterruptible power supply is justified by the fact that it converts 24vdc battery to a 220vac, 5kva output which can be used to power a essential circuit such as computers, surgical equipments security door etc.
1.5 PROJECT LIMITATION
- The work has been limited by lack of funds to make the researcher to search for the necessary information for this work, despite the above limitations, the researcher has been able to work efficiency by using the primary data (interview and questionnaire)
- Due to financial problem and time factor within this researches, this work will be limited to the construction of 220v 5kva uninterrupted power supply.
- Anther limitation is the used of bulky transformer instead of copper transformer which is lighter and smaller in size but more expensive.
1.6 DEFINITION OF TERM
This area shall look on the related and important definition in this project
- UNINERRUPTED POWER SUPLLY: An uninterrupted power supply is a device that allows a system to keep processing for at least a short period time when the main sources lost.
- INVERTER: Ann inverter is a device which changes the direct current (DC) into an alternating current (AC) power.
- TRANSFORMER: A transformer is a static (stationary) electromagnetic energy converter device which transforms electric power from one point to another with the same frequency.
- CAPACITOR: A capacitor a device for storing electrical charges. It consists of two conductors which are parallel to each other.
- TRANSISTOR: A transistor a semi conductor device use to amplify and switch electronics signal
- RELAY: A relay is an electrical device that open and close a circuit electronically or electromagnetically.