Design and Construction of a Single Phase Auto-Transformer of Rating IKVA, 240V/110V, 80v, 12V, 6V
Chapter One
THE AIM OF STUDY
Our study aims to design and construct an auto-transformer that can step down 240V from the local supply down to 110V, 80V, 12V, and 6V, to meet the various voltage requirements of numerous electrical and electronic appliances, often appliances imported from say America where the domestic voltage level is 110Volts.
This auto-transformer can conveniently do this at a relatively cheap cost or rate. The output of this transformer is made by numerous taps on the primary winding, depending on the required output.
CHAPTER TWO
LITERATURE REVIEW
Transformers a defined to be a static electrical machine this used to either step-up voltage or step-down voltage, have a lot of theories, principle, types as it literature. Review in this project. The mgor principle of its operation is electromagnetic principle. It could have an iron core which is made up of “E” and “I” shaped lamination interleaved so that the magnetic flux does not pass through air. The greatest flux is obtain with a given current when an alternating electromotive force is connected to the primary winding. This sets up an alternating flux in the core of magnitude BA, where B, is the flux density and A, is the cross-sectional area of the transformer.
Another major principle that transformer works on is electromagnetic induction principle. There are two types of induction; self induction and mutual induction. This induces an alternating electromagnetic force in the secondary V2 of a transformer. There are mathematical expression i.e formulae use when analyzing the principle of operation of transformer. The types of transformers as mentored above, is of varies, type but the major concern in this project is auto-transformer which also works on the principle mention above.
DEFINITION AND OPERATION OF AUTO-TRANSFORMER
An auto-transformer is a transformer with one winding only, part of this being common to both primary and secondary. Obviously, in this transformer the primary and secondary are not electrically is elated from one another.
Auto-transformer is also used in stepping up and down bulk electric power; but it is used mostly where a slightly less or above the supply voltage to needed. His help in the saving of winding material. Depending on the design. Some electrical machines make use of such voltages provided by an auto-transformer of their efficient operation like starting of a.c. machines, where the voltage is raised in two or more steps from a small value to the fall supply voltage; continuously variable a.c. supply voltage; production of very high voltages. An auto-transformer can also be used to provide small power to some electronic sets such as Radio, television, piano, computer, electric grinding machines, power level needed by these equipment can be as how no to 5V.
There is a particular features which an auto-transformer possesses, and of coarse which makes of different from other types of transformer. These is the fact that of has a common (single) winding for both the supply voltage and the output voltage.
This special feature makes of relatively cheap, and easy to construct. Although inherently are small disadvantages.
CHAPTER THREE
CONSTRUCTION
Construction is an important factor in making a new auto-transformer. There are three distinct types used in the construction of a transformer. They are Barry tape, core type and shell type.
In this construction, we used the shell core type. This type increases the magnetic (coupling and therefore increases in auto-transformer efficiency because of provides two parallel magnetic paths for the magnetic field.
The auto-transformer consists of a single coil with tapings of desired points to form the common coil and the series coil to the supply.
The construction consists of the following.
CHAPTER FOUR
CONCLUSION
The aim of this project is to design and construct an auto-transformer to a specification of 1KVA with output voltages of 110V, 80V, 12V, and 6V. The input voltage being 240 – 250 volts of the supply.
This is the test performance of auto-transformers, to produce various required voltage levels to suit producers demand and taste. It also enables individual to use the desired voltage at any given time. There will be no need to convent the input voltages of American equipments in other to suit our voltage range. One can easily use the 110V tappings of the usage of those equipments.
RECOMMENDATIONS
The utilization of local raw material on a large scale is now being given adequate consideration in different developing countries of the world. There are various benefits in the use of local raw materials in the production of our basic needs. Therefore, all hands must be put together for the realization of this goal. Workshops, seminars, and research greats should be provided to enable individuals to embark on this kind of production in masses.
Subsidy should be provided to encourage individuals and to improve the quantity of this kind of projects.
REFERENCES
- Edward Hughes “Electrical Technology” ELBS London – 1977.
- Institution of Electrical Enginars” IFE Regulation 15th Edition – London – 1981.
- Nerale “Michael and Neo-Better Words Electrical Installation Technology ELBS London – 1978.
- “At Sir Isaac Pitman and Sine Total Applied Electricity London – 1957.
- Wayton P.E. Fundamental of Electrical Technology Addison Wisely Publishing Company London – 1977.
