DESIGN AND IMPLEMENTATION OF AUTOMATIC 3 – PHASE CHANGE – OVER WITH GEN SET SWITCHING

DESIGN AND IMPLEMENTATION OF AUTOMATIC 3 – PHASE CHANGE – OVER WITH GEN SET SWITCHING

CHAPTER ONE

INTRODUCTION

The evolving trend in industrial electronics and automation has engulfed the entire world, making it more difficult for third-world countries such as Nigeria. In terms of the milestone, it was decided to conduct project research on the design and implementation of an automatic three-phase changeover with generator switching, which will eliminate the stress and lapses associated with the manual process. This electronics system is built around a three-phase regulated direct current power supply unit, the output of which is compared and fed to a three-input AND gate, which encodes control logic to the driver stage, which is built around NPN Bipolar junction transistors that power three electromagnetic relays. These relays, in turn, activate single coil three contactors, which switch the phases. Manaha (2008) A control/switching circuit is also integrated, which handles the switching of the generator whenever at least one phase from the mains is low/faulty.

1.1.                GENERAL DESCRIPTION OF THE PROJECT

The project design and implementation of automatic three-phase changeover with generator switching is made up of several functional blocks that are all combined to form one functional unit. The first consists of a regulated DC voltage power supply unit, the output of which is compared and fed into the 74 LS11, which generates the control logic. This logic is used to bias the driver stage, which is responsible for energizing the electromagnetic relay. These relays supplement a single coil 3 – contact contactor of appropriate rating. The process is handled by the Gen set switching module, which includes a delay timer and a solid state relay.

For compatibility, the project is packaged in a plastic casing. Three 100k vol/pot are located on the package’s surface. Low voltage in a given phase is used to demonstrate this. Three amber LEDs represent the mains, while three blue LEDs represent the generator. And these comprise the panel indicator.

1.2.          OBJECTIVES OF THE PROJECT

One of the goals of this project is to design and build an automatic three-phase changeover with gen set switching capability that will automatically switch ON/OFF the gen set and switch between PHCN and the gen set. It also aims to expose graduating students to electronics system design using random logic, particularly in industries and power electronics. Another goal of this research is to provide graduating students with a solid foundation in engineering, scientific, and technical writing, which is essential in their professional practice.

1.3.  SIGNIFICANCE OF THE PROJECT

This project work is significant in the fields of industrial automation and power electronics. It is extremely useful in the wood processing industry, oil rig equipment, and other manufacturing industries that use three-phase machines. This project can be modified to function as an automatic phase selector that can be used anywhere.

1.4.  SCOPE OF THE PROJECT

This project work includes transistor drivers, electromagnetic relays, contractors, a three-input AND gate encoder, shunt regulation and a comparator using a Zener diode, a delay/un-delay timer, and other system components. It examines the basic circuit parameters and system application areas’ design calculations.

1.5.  PROJECT REPORT ORGANIZATION

This project report is divided into six chapters to better illustrate the steps involved in its execution.

The first chapter introduces the project’s objectives and significance. The chapter consists primarily of a literature review and some design-related theories. The methodology and analysis are examined in Chapter 3, while the system design and description are covered in Chapter 4. The fifth chapter goes over the implementation, testing, and results. Finally, chapter six is a summary of all theories and recommendations.