Design, Construction And Experimental Performance Analysis Of 1.5KVA Variable DC To Constant AC Single Phase Inverter

ABSTRACT

Solar energy is considered as fastest growing renewable energy source after wind energy for electricity generation. Solar energy is a free, clean abundant sun energy considered as inexhaustible source for electricity generation. Solar photovoltaic system is characterized with variable output power due to its operation dependency on solar irradiance and cell temperature. To maximize the energy generation potential of solar PV, research effort is focused on solar cell manufacturing technology to increase its generation efficiency and exploring advancement in power electronic devices for small and large scale deployment. Presented in this paper is a single phase inverter with no transformer which have a variable input voltage with a constant AC output voltage for solar PV application .

TABLE OF CONTENTS

COVER PAGE

TITLE PAGE

APPROVAL PAGE

DEDICATION

ACKNOWELDGEMENT

ABSTRACT

CHAPTER ONE

INTRODUCTION

1.1      BACKGROUND OF THE PROJECT

• PROBLEM STATEMENT
• AIM/OBJECTIVE OF THE PROJECT
• ADVANTAGES OF THE PROJECT
• SCOPE OF THE STUDY
• LIMITATION OF THE STUDY
• SIGNIFICANCE OF THE STUDY
• RESEARCH METHODOLOGY
• PROJECT ORGANISATION

CHAPTER TWO

LITERATURE REVIEW

• OVERVIEW OF THE STUDY
• LITERATURE SURVEY OF THE STUDY
• SINGLE PHASE PULSE WIDTH MODULATED INVERTERS
• VOLTAGE CONTROL IN SINGLE – PHASE INVERTERS

CHAPTER THREE

METHODOLOGY

• PROPOSED DC TO AC CONVERTER
• SYSTEM BLOCK DIAGRAM
• SYSTEM CIRCUIT DIAGRAM
• WORKING PRINCIPLE

CHAPTER FOUR

RESULT ANALYSIS

• RESULTS

CHAPTER FIVE

• CONCLUSION
• SCOPE OF FUTURE WORK
• REFERENCES

CHAPTER ONE

1.0                                                       INTRODUCTION

1.1                                          BACKGROUND OF THE STUDY

In order to meet the rising global energy demand from sustainable environmental friendly sources, various renewable energy is now given adequate attention. Renewable energy comes from energy sources that naturally regenerate over a short period of time. Some are derived from the sun like thermal and photoelectric and other from natural movements of the environment like the wind, rain fall, and geothermal energy [T. G.Wilson, 2000]. In the nearest feature, solar and wind energy are expected to contribute more than 30 % of renewable energy within the power industries [Channaveer, 2012]. Solar energy is presently considered as fastest growing renewable energy source after wind energy for electricity generation [Channaveer, 2012]. In a span of five years, the world solar PV electricity generation increased from below 10 GW in 2007 to over 100 GW operating capacity in year 2012 [Roman, 2013]. Research efforts towards maximizing solar energy advantage are now focused on how to increase efficiency of solar cells via manufacturing technologies and to explore the advancement in power electronic devices to be able to adapt the solar PV generation for small and large scale power system application.

The link between solar energy generator and the loads is an efficient power converter that delivers the generated energy. Power converters are used to improve the power quality of solar photovoltaic system because of associated intermittency and continuous variation. The generated power from solar PV are DC component and mostly at different level from the load demand, so there is a need for voltage regulation and conversion to AC component for AC loads application.

Presented in this paper is a design and simulation of single phase inverter with wide input voltage range which is suitable for variable solar photovoltaic source. Supply voltage from the solar panel is first regulated and boosted to high DC voltage which is then subsequently converted to AC voltage for AC load supply. After filtering, the output voltage of the inverter shows that the system is suitable for local AC load and grid connection has a very low total harmonic distortion of less than 1 %.

1.2                                           PROBLEM STATEMENT

Conventionally, inverter input voltage always affect the out of the inverter. The variation of the input voltage always varies the frequency of the inverter thereby making it difficult for the inverter to carry a load with its optimum capacity and also makes it difficult to be used with renewable energy because renewable energy voltage like solar varies according to sun radiance. To overcome this problem, an inverter with a variable dc source to a constant ac output was built.

1.3                            AIM AND OBJECTIVE OF THE STUDY

The main aim of this work is to design and to carry out an analysis of a single phase inverter with a variable dc source and constant output ac. The objectives of the study are:

1. To build a low cost inverter that is supplied with a variable input voltage which can be used for small Distributed generation
2. To provide a solid state, low cost variable input voltage inverter featuring an improved commutation circuit that produces reliable commutation over a wide range of output voltage.

• To conduct a design and analysis of single phase inverter with wide input voltage range which is suitable for variable solar photovoltaic source

1.4                                  ADVANTAGES OF THE PROJECT

The functions of inverters for small Distributed generation (DG) systems can be summarized as follows [Channaveer.P.Malad , K.Uma Rao, 2012].

• It converts power conversion from variable dc voltage into fixed ac voltage for stand-alone applications and ac output in synchronism with the grid voltage and frequency for grid-connected
• Variable dc voltage can be higher or lower than the ac voltage in a system, which is observed normally in a solar energy and wind turbine systems. Thus, there is a need to buck boost the inverter

1.5                                                                SCOPE OF THE STUDY

Inverters are the devices usually solid state which change the array DC output to AC suitable voltage, frequency and phase to feed photo voltaic ally generated power into the power grid or local load. Solar energy is time dependent and intermittent energy resources. Inverter may also contain a suitable output step up transformer perhaps some filtering and power factor correction circuits and some power conditioning circuitry to initiate the battery charging and to prevent overcharging .Inverters of PV system based distributed generation (DG) are subjected to wide changes in the inverter input voltage, thus demanding a buck-boost operation of inverters . Further the inverter size, weight and cost is increased. It is designed transformer less inverter that can be operated over a wide dc input voltage range making it suitable for distributed generation applications. Depending on the reference signal the inverter output voltage can be either boosted or bucked with respect input voltage.

1.6                                                        LIMITATION OF THE STUDY

As we all know that no human effort to achieve a set of goals goes without difficulties, certain constraints were encountered in the course of carrying out this project and they are as follows:-

1. Difficulty in information collection: I found it too difficult in laying hands of useful information regarding this work and this course me to visit different libraries and internet for solution.
2. Difficulty in parts gathering: I found it too difficult when gathering electronics parts used for the prototype.

1.7                                                      SIGNIFICANCE OF THE STUDY

This research work will throw more light on the best techniques for using solar energy with an inverter.

It will also serve as a guide to whoever that is into solar installation and inverter production

Finally, it will also serve as a useful piece of information for both producers and users of renewable energy.

1.8                                             RESEARCH METHODOLOGY

In the course of carrying this study, numerous sources were used which most of them are by visiting libraries, consulting journal and news papers and online research which Google was the major source that was used.

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.