Comparative Analysis Of 2.5Kva Inverter, Locally Versus Foreign Made

1.0 INTRODUCTION

Due to today total dependence on electricity and because of the frequent power outage, backup power is becoming a necessity. Emergence backup system can provide electrical power to critical loads or the whole house during power outages. Emergence power system is types of system which may include lighting and other apparatus, to provide backup resources in a crisis or when regular system fails. They found uses in variety of setting from residential homes to hospitals, scientific laboratories and computerized systems. They can rely on generators or uninterrupted power supplies. In our society today, the need for power supply cannot be overemphasized because the provision of goods and services could be completely cut off without power supply.

Power electronic systems are used widely to convert electric energy from one form to the other using electronic devices. Four basic power electronics functions are AC to DC conversion, DC to AC conversion, DC to DC conversion and AC to AC conversion. These basic functions are used to build power supplies, DC transmission systems, electric drives and others. In today’s scenario the demand of electricity has increased tremendously. The cause of it is increase in population day by day, economic development of a country and diminution of fossil based fuels. So alternative energy sources i.e., renewable energy sources are the best option without any harm to the nature. With the advancement in technology in the field of power electronics more than past few years and rising crises for energy have led to increase progress in generating power using renewable energy sources like Photovoltaic (PV), Wind, Fuel cell (FC) based renewable energy technologies. Among all renewable energy sources, solar photovoltaic (PV) electricity generation is the fastest growing source now are days throughout the world. In a PV system, a PV array converts solar power to electrical power and a grid connected inverter is required for inverting the electrical power to ac power then it is fed back to the grid. The power electronics device which converts DC power to AC power at required output voltage and frequency level is known as inverter.

At present time almost all instruments whether electrical or electronic require power inverter. The instruments which use ups (uninterruptible power supply) are mostly square or quasi sine wave inverters. They have large harmonics in their output and may damage the devices or electronic instruments. For getting pure sine wave are posed with a major problem of power shortage especially here     in Nigeria. Although in developing countries, shortage of power is a problem commercially and domestically. New offices have tremendous load on already existing power generation sources. When added to rapidly increasing private and domestic demand, the situation, especially in certain urban areas becomes devastating. Simply stated, our ability to consume power is growing faster than our ability to supply power. Under such conditions, failure will occur unpredictably and without any warning due to stresses on the inadequate sources of power. Hence, there is need for the alternative source of power which could fill in the gap and cover the lapses of shortage in power supply. Overcoming this obstacle led to the invention of DC/AC power inverters. Short term solution of power disruption could be addressed through this project work. The system embraces the use of electronic means to generate electricity. It involves the conversion of direct current (DC) source from the battery to alternating current (AC) that can be used to power our house, offices, hospital, banks etc. This system also incorporates an AC to DC converter which serves as a charging system, responsible for recharging the batteries when they go below a threshold value of 18V. The aim of the study is to evaluate and analyse the performance of a foreign branded and locally constructed Modified 2.5kva Sine Wave Power Inverter for domestic electric power supply.

1.2 BACKGROUND OF THE STUDY

Over the years electricity has been generated through energy conversion from one form to another; solar, thermal, wind, electric generators these are some of the sources. They have all proved to be quite reliable and sufficient but due to inadequate source of energy to run the engines, faults in the systems, it self-poor maintenance, they fail the users at one time or the other. Apparently, man rely on power supply facet of their activities as in our houses, offices, computer, security systems, farming and so on, in the most third world countries, power supply is not reliable; Nigeria and majority of the Africa countries which are often termed “developing countries” are not exempted from this problem of unreliable power supply. So with the erratic power supply, it is quite evident that there is need for this alternative source of supply. As such the need for standby power supply is essential which brought into existence an alternative means called inverter.(Thorborg, 1988)

Inverter is power electronics devices which convert direct current (DC) into an alternating current (AC) its function is to change the DC input voltage to asymmetrical AC output voltage of the desire magnitude and frequency which is determined by inverting transformer. The output power is determined by drive MOSFET along side with inverting transformer. The possible inputs are batteries, fuel cell, solar cell or DC sources. And for one to fully enjoy the better part of this ‘continuously advancing’ world there should be an adequate stable source of power supply. As in our society today, the provision of goods and services could be completely cut off without power supply.

1.3 PROBLEM STATEMENT

There has been a problem of making choice when it comes to buying of inverter and the choice is between locally made and foreign/imported inverter. This study was written to address this problem. At the end of this study the advantages of the locally and foreign made and their differences shall be discussed which will serve as points that will be looking at when it comes to choice to an inverter.

1.4 AIM AND OBJECTIVES OF PROJECT/RESEARCH
1.4.1 Aim
The aim of this project is to design and construct a 2.5kva locally made inverter and compare it performance analysis with an already made 2.5kva inverter.

1.4.2 Objectives

• To research about design method of a 2.5kva inverter circuits and come out with a workable, implementable, and cost effective circuit
• To create backup power supply system which is eco-friendly
• To implement hardware (solder the components together) for the project.
• To design an alternative source of electricity which is save and suitable to run most electrical/electronic appliances

1.5    MOTIVATION OF THE STUDY
Many electronics equipment and appliances were being fed with an alternating current but the conventional power supply 220V phase voltage and 415V line voltage in the country by Abuja electricity distribution company (AEDC) is not reliable. In fact, not all sites are connected to the grid.

Due to the frequent power outages in the country, there is growing needs for backup supply that can supply alternative current suitable to basic electrical and electronics appliance like the television, lighting system, fan, computer, audio system etc. The most common backup supply system available in the market are automotive generator sets (convert mechanical energy into electrical energy by means of burning fossil fuel) and UPS (uninterrupted power supply). Even though all this backup supply system turns to pose challenges; the generator produces carbon monoxide which pollutes the environment making it non-environmental friendly. The cost of running such backup system turns to be expensive since they run on fuel.

UPS is eco-friendly but is also design to provide backup for a short period of time, which makes it not ideal for backup systems intended to run appliances for long periods of time. All of these thence give rise to the designs and constructions of inverters of different power ratings both locally made and foreign by many technologist, nowadays inverters are so much versatile but still a bit expensive at which one has to think twice to get one. Nonetheless people tend to purchase that of foreign made and thus left the locally made once handicap. This project work is aim at analytically comparing the corresponding performance of these inverters; the specifications majorly on both terms (local versus foreign), 2.5KVA to be specific.

1.6 CONTRIBUTION TO KNOWLEDGE
This project seeks to improve on the existing power inverters and bring forth new innovative features and upgrades such as;

1. The availability of a low cost constant power source (areas of frequent power outage).
2. Low cost modified sine wave inverter.
3. Battery charging system (for external voltage source).
4. Cooling system which allows the inverter to run continuously without any out-heating.
5. Automatic load transfer and switching to avoid computer based system from restarting.
6. Low power consumption.

1.7 SCOPE AND LIMITATION OF PROJECT

This locally made inverter is designed to;

1. Create an inverter which is reliable, durable and thunder resistive compare to some imported once.
2. Increase the supply rate of electricity for home and industrial usage.
3. Reduce the high rate of importation of already made inverters (foreign).
4. Create an enabling environment to enlighten interested indigenes on how to design and construct an inverter inform of orientation/seminar.
5. Create employment opportunity.

1.7 STRUCTURE OF THE REPORT
The comparative study and evaluation of the design and performance of a 2.5kva inverter is divided into chapters, the chapters are;

Chapter 1; Generally an introduction on inverter using 2.5kva locally source made as a case study.

Chapter 2; looks at the literature on the design of 2.5kva inverter, the component use and principal of construction will also be discussed here.

Chapter 3; Involves adopting engineering methodology, on the design and construction of a 2.5kva locally made inverter. This will include the design parameters and the various rating of the component used.

Chapter 4; Deals with the performance analysis that is; testing the locally made 2.5kva and comparing it with an imported/already made 2.5kva (foreign) and plotting their various graphs with table of value at the various loads connected.

Chapter 5; Includes the conclusion, summary and recommendation. There after follows the references.