ABSTRACT

Despite all attempt of the federal government to have not only an uninterrupted power supply for all cities in Nigeria, but a voltage that is inconformity with the recommended 220/230v for domestic consumption for example.  The NEPA Plc is facing some difficulties in generating, transmitting and distributing the required voltage stabilizer, which could be connected, to the main and then the load is in turn connected to it.

This automatic, AC voltage stabilizer has two major sections.

The transformer section, the control circuit unit the third section is the protective unit.

The output of this voltage stabilizer after series of test were performed on it  has a voltage 228 + 12 at an overall output power of 1.5 KVA.

TABLE OF CONTENTS

TITLE PAGE

CERTIFICATION

DEDICATION

ACKNOWELDGEMENT

TABLE OF CONTENTS

LIST OF TABLE 

ABSTRACT

CHAPTER ONE

1.0 INTRODUCTION

1.1 THE TRANSFORMER UNIT

1.2 THE CONTROL CIRCUITING

CHAPTER TWO

2.0 LITERATURE REVIEW

2.1 HISTORY OF THE PROJECT

2.2 THE POWER SUPPLY

2.3 THEORY OF TRANSFORMER

2.4 OPERATION OF THE TRANSFORMER

2.5 VOLTAGE TRANSFORMATION RATION 

2.6 TRANSFORMER LOSSES

CHAPTER THREE

3.0 THE CONTROL CIRCUITING

3.1 TRANSISTORS

3.2 RELAY

3.3 THE CONTROL UNIT

3.4 THE POWER SUPPLY UNIT

3.5 VOLTAGE DIVIDER

CHAPTER FOUR

4.0 DESIGN ANALYSIS

4.1 DESIGN FO A TRANSFORMER

4.2 DESIGN OF THE TRANSFORMER PROPER

4.3 CONTROL CIRCUIT DESIGN

4.4 DESIGN CALCULATION

4.5 PRINCIPLE OF OPERATION

CHAPTER FIVE

5.0 CONSTRUCTION AND TESTING OF THE TRANSFORMER

5.1 SHORT CIRCUIT TEST

5.2 TESTING OF THE TRANSFORMER 

5.3 OPEN CIRCUIT TEST

5.4 SUMMARY 

5.5 CONCLUSION

5.6 RECOMMENDATIONS

5.7 REFERENCES

LIST OF FIGURES

CHAPTER ONE

1.0 Block diagram representation of the voltage stabilizer

CHAPTER TWO

2.0 The Sheel Type Transformer

CHAPTER THREE

3.0 Circuit Diagram of 1.5 KVA Automatic Voltage Stabilizer

3.1 Transistor Diagram

3.2 Relay Diagram 

3.3 Block diagram for a typical power supply with corresponding Wve form for each stage

3.4 Exact circuit diagram for the power supply stage have the automatic voltage stabilizer 

3.5 Block diagram of voltage divider

CHAPTER FOUR

4.0 Schematic representation of the transformer with different voltage level.

4.1 Size of the lamination used for the design and construction of the transformer

4.2 Graph of (Max) against VCB

4.3 The comparator circuit diagram

CHAPTER FIVE

5.0 Short circuit test

5.1 Open circuit test

5.2 Casing diagram