1.0 Introduction
A machine has been defined as a device that helps in doing work easily and accurately when energy is applied. Also electrical energy is one of the most useful sources of energy for the operation of both industrial and household machines.
Therefore, electricity has been said to be an instrument for the industrialization and empowerment of man for better standard or living. Since most of the industrial and household machines are digitally operated when there is power failure, the commands (information) stored in their memory loss out, this makes their execution difficult and possible cause damage in the production activity.
This electric power failure is of critical concern in the operation of most industrial and household equipments (machines) such as data processing systems, health case equipment (machines), telecommunication links, etc. Therefore, since power outage is inevitable in Nigeria, Its damage to the smooth running of these digitally operated device can never be ignored.
Alternatively, a standby power supply such as automatic diesel/petrol generator set have been employed to check the problem, but due to high cost of installation and running of such generator sets, can only be afforded by organizations and few individuals.
Also, there are commercially available uninterruptible power supplies (UPS), as medium and low capacity standby power supply. Therefore there is a need for the production of such uninterruptible power supply with readily available and low cost components. Hence the main focus of this project is to design and construct a UPS by converting D. C. power into A.C. power using inverters. Switching device are the simplest form of inverters and are used here because of their higher efficiency, smaller size and weight. There are other methods of converting D.C. Such as converting machinery like synchronous rotary converters, solid state converters, and motor generator sets, etc.
The common applications of inverters are:
- They are use to provide uninterruptible power supply to computers.
- Used in providing emergency lighting whenever there is power failure from the supply authority.
- Used in food processing industries where short interruption of power may spoil foodstuff.
- Used in speed control of induction motors.
1.1 History and Development of Ups
The development of an uninterruptible power supply system paralleled the increase dependence of the society on electric power to provide motive power and intelligence for all aspects for modern life. These systems have become necessary since the 1920's in areas of medical and telecommunication applications standby power supply systems set dates in 1920 with the work of Admiral Byrd which was extensively used in medical institutions. Gasoline and diesel engines was used during the world war II, as well as in microwave communication in 1955 and this was developed by N.B Tharp.
In the late 1950's J.J Gano developed the storage battery for powering telephone central office, also the start of the computer age saw the development of the UPS using motor generator. in the area of modern UPS, the works scientist Dr. J.D. Standler and Engr. Libert whose works on the solid state UPS cannot be overlooked. Therefore as long as the need for the solution of the problem of public power failure continues, the need for the modification of the UPS will constantly continue.
1.2 Aims and Objectives of the Project
The aim and objective of the design and construction of an uninterruptible power supply follows. Firstly, the primitive concern of providing quality and adequate power to sensitive devices like the medical faculties, data processing and communication centres.
Secondly, this work aim at the satisfaction of the statement of Alexander Kusko in his book Emergency/standby power system, that as the quest for the solution of the problem of public power failure continues, the need for the modification of the UPS will constantly be continued; by this we hereby aimed at modifying the already existing UPS.
This material contains electrical diagrams, circuits, illustrations and more (Very detailed)
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