CHAPTER ONE
INTRODUCTION
As the growing population of human race widens the gulf between energy supply and energy demand, the imbalance in energy availability sent researchers into excavating for a way of settling this age long squabble. A lasting solution is vested on alternative use of the renewable energy source, a project that is yet to be widely applied. Hence, the continuation of the unsettled yearns for sufficient power. Consequently, the power lines are frequently over loaded resulting to a trip of power by the action of switch gears or by the load shading process undertaken by the distribution authorities.
Since it is crystal clear that some institutions such as health related institutions and some other delicate systems should not be allowed to suffer equally with their counterparts, Automatic Phase Selector is used to sustain energy consumption in the time of phase trip. The design of this circuit involves the use of automatic switches but the details of design varies from place to place, time to time and also depends on the type of load involved.
This project involves the use of transistor driven relays to affect the change of phase whenever the voltage condition becomes intolerable in the previous phase connected.
1.1 BACKGROUND
The intelligent phase selector is a system that is capable of comparing three phases and switching automatically to any of the three phases. The system consists of three main parts namely; the transformer, comparators (which is the brain of the system) and electrical switching device (relay).
The transformer used here is the step down type of transformer (it step down 240v to 12v) and these transformer is feed in with different phase voltage, rectified and smooth. Then fed in to a voltage regulator that has positive output. The regulator outputs were connected to comparators. Here the comparators are three in number. We call the comparators the brain of the system because these comparators are connected in a way that each of them will give out an output.
The relay in the system is where the output voltage is connected. In this project we even went as far as using pictures for illustration of some components.