CHAPTER ONE

INTRODUCTION

All modern engineering system include certain aspects of control systems at some point in their broadcast sense, control engineering and  the associated theory are concerned with the means by which systems may be made to behave an a desired way.

          The system on this thesis is a DC – AC converter, which is an apparatus which is used for conversion of Direct Current to Alternating Current or signal.

          In our country, this equipment is not all that in used not because it is not important but because people never give it a thought as per the construction and design.

          It is meant, use with a 12v lead acid battery. If it’s in a car for example a suitable output voltage of 230v AC is obtainable.

          This output voltage of 230v AC can be used for powering small electrical appliances such as light, electric fans, radio, soldering iron etc.

However, it is worthwhile that AC operated with this appliance is nothing comparable to the AC generated by big generators. This is so because the voltage and power are less in terms of AC generation duration. This appliance is therefore suitable for short time replacement for the real AC generation especially in the remote areas and install where electrical appliances are sold and the need might arise for it to be tested and certified good.

          Another main area where this equipment can be of great utility is in communication system. in a situation where there is constant AC power supply failure e.g in offices, DC – AC converter is need and in such cases can be used  as a light sources.

          Most industries in the country do not make use of DC – AC converter because they are thought to be costly with respect to the task they perform. However, putting into consideration the task this appliance  can be used for, it can be concluded that it is cheaper. The construction is simple, cheaper easy to operate and portable. The usefulness of this device and the function cannot to be over emphasize now in our economic situation and also when our power generating authority (NEPA) has been dubbed NEVER EXPECT POWER ALWAYS.

In these times when control and monitor a complex field engineering operations have gone computer based, a failure of AC power supply to communication equipment means work stoppage and to some small scale industries a lot of economic and material losses avoidable.