Design And Construction Of Current Boost Power Supply From 80-220V

ABSTRACT

This project involved the design of a high-voltage DC-DC booster capable of converting 80VDC into 220VDC. The design is based on a half bridge topology utilizing power MOSFET switches, a custom center-tapped transformer, and an all- analog feedback control system. The control circuitry worked as expected, however the power-side switching posed several issues that remain to be resolve.

TABLE OF CONTENTS

COVER PAGE

TITLE PAGE

APPROVAL PAGE

DEDICATION

ACKNOWELDGEMENT

ABSTRACT

CHAPTER ONE

INTRODUCTION

1.1      BACKGROUND OF THE PROJECT

• PROBLEM STATEMENT
• OBJECTIVE OF THE PROJECT
• SIGNIFICANCE OF THE PROJECT
• LIMITATION OF THE PROJECT
• APPLICATION OF THE PROJECT
• DEFINITION OF TERMS
• METHODOLOGY
• PROJECT ORGANISATION

CHAPTER TWO

LITERATURE REVIEW

• OVERVIEW OF HIGH-VOLTAGE DIRECT CURRENT
• APPLICATIONS OF HVDC IN POWER TRANSMISSION
• HISTORICAL BACKGROUND OF HVDC

CHAPTER THREE

SYSTEM METHODOLOGY

• SYSTEM REQUIREMWNT
• METHOD OF IMPLEMENTATION
• SYSTEM BLOCK DIAGRAM
• CIRCUIT DIAGRAM AND DESCRIPTION
• CIRCUIT DIAGRAM AND DESCRIPTION
• PARTS LIST

CHAPTER FOUR

• CONSTRUCTION PROCEDURE AND TESTING
• CASING AND PACKAGING
• ASSEMBLING OF SECTIONS
• TESTING OF SYSTEM OPERATION
• COST ANALYSIS

CHAPTER FIVE

• CONCLUSION
• RECOMMENDATION
• REFERENCES

CHAPTER ONE

• INTRODUCTION

1.1                                           BACKGROUND OF THE STUDY

A boost converter is a DC to DC converter with an output voltage greater than the source voltage. A boost converter is sometimes called a step-up converter since it “steps up” the source voltage. A process that changes one DC voltage to a different DC voltage is called DC to DC conversion. A boost converter is a DC to DC converter with an output voltage greater than the source voltage. A boost converter is sometimes called a step-up converter since it “steps up” the source voltage.

It is a class of switched-mode power supply (SMPS) containing at least two semiconductors (a diode and a transistor) and at least one energy storage element: a capacitor, inductor, or the two in combination. To reduce voltage ripple, filters made of capacitors (sometimes in combination with inductors) are normally added to such a converter’s output (load-side filter) and input (supply-side filter).

1.2                                   PROBLEM STATEMENT

Engineers working in today’s high tech environment have to deal with a rapidly changing market of electronic products and equipments. As new technologies are invented, integrated circuits function faster and are smaller in size and shape. But, many integrated circuits still require a voltage of 80 volts to function. The DC-DC Switching Boost Converter will take a 80 Volt DC voltage supply with ±10 % tolerance and deliver 220 Volts to the load.

1.3                                               OBJECTIVE OF THE PROJECT

The main aim of this work is to construct an electronic circuit that converts a source of direct current (DC) from low voltage level to a higher voltage. It is a type of electric power converter. At the end of this work, student involved shall be able to design this device which when powered with 80v will produce an output of 220vdc.

1.4                                              SIGNIFICANCE OF THE STUDY

This device offers a method to increase voltage from a partially lowered voltage thereby saving space instead of using multiple circuits to accomplish the same thing.

1.5                                              LIMITATION OF THE PROJECT

This device has a number of disadvantages:

1. High ripple currents occur at the input and output.
2. A large inductor is required, since large amounts of energy must be temporarily stored.

• The load on the semiconductors is high.

1. The efficiency is poor.

Overall, the use of a boost converter is associated with additional costs, weight and volume. Furthermore, the overall efficiency of the inverter circuit is decreased by the additional losses in the boost converter.

High voltage modules present a serious risk of injury if the operator is not fully aware of the inherent dangers presented by the use of high voltages in circuit design. If untrained or unqualified personnel do not properly adhere to the proper handling, design, or testing of high voltage devices there is a risk of electrical shock. All instructions, circuit designs as well as industry standard safe handling procedures must be followed for high voltage usage.

1.6                                            APPLICATION OF THE PROJECT

i.                   Aerospace

ii.                 Industrial/Semiconductor Fabrication

iii.              Medical

iv.              Military/Defense

v.                 Scientific

1.7                                                    DEFINITION OF TERMS

Step-down: A converter where output voltage is lower than the input voltage (such as a buck converter).

Step-up: A converter that outputs a voltage higher than the input voltage (such as a boost converter).

Continuous current mode: Current and thus the magnetic field in the inductive energy storage never reach zero.

Discontinuous current mode: Current and thus the magnetic field in the inductive energy storage may reach or cross zero.

Noise: Unwanted electrical and electromagnetic signal noise, typically switching artifacts.

Input noise: The input voltage may have non-negligible noise. Additionally, if the converter loads the input with sharp load edges, the converter can emit RF noise from the supplying power lines. This should be prevented with proper filtering in the input stage of the converter.

Output noise: The output of an ideal DC-to-DC converter is a flat, constant output voltage. However, real converters produce a DC output upon which is superimposed some level of electrical noise. Switching converters produce switching noise at the switching frequency and its harmonics. Additionally, all electronic circuits have some thermal noise. Some sensitive radio-frequency and analog circuits require a power supply with so little noise that it can only be provided by a linear regulator. Some analog circuits which require a power supply with relatively low noise can tolerate some of the less-noisy switching converters, e.g. using continuous triangular waveforms rather than square waves.

1.8                                         METHODOLOGY

To achieve the aim and objectives of this work, the following are the steps involved:

1. Study of the previous work on the project so as to improve it efficiency.
2. Draw a block diagram.

• Test for continuity of components and devices,

1. Design was carried out.
2. Studying of various component used in circuit.
3. Construct the circuit.

• Finally, the whole device was cased and final test was carried out.

1.9                                                         PROJECT ORGANISATION

The work is organized as follows: chapter one discuses the introductory part of the work, chapter two presents the literature review of the study, chapter three describes the methods applied, chapter four discusses the results of the work, chapter five summarizes the research outcomes and the recommendations.