technical project

Department of Electrical and Computer Engineering

Session: Sem B, 2016-17

BENG (Honours) in Telecommunication Engineering

MHH121511: Technical Project Report

Project Title: Solar power supply (power bank)

Student Name: Sara Salah Al.deenA.moniem

Student Number: 120318

Supervisor Name: Mr. Ali Almahruqi

I declare that this project report / dissertation titled Solar Power Supply (Power Bank) is my own work and has not been submitted in any form for another degree or diploma at any university or other institutions of tertiary education. Information derived from the published work of others has been acknowledged in the text and a list of references is given. I am fully aware of the College’s policy on plagiarism and cheating, and that the penalty for submission of plagiarized report could result in a ‘fail’ in Technical Project / Dissertation. I have submitted a copy of this full report in electronic form to my supervisor.

Signature Date

Name Sara Salah Aldeen A.Moniem

Student Number 120318

CERTIFICATE BY THE SUPERVISOR

The project report / dissertation titled Solar Power Supply (Power Bank) is the bonafide work of Sara Salah Alden, carried out under my supervision. I certify that the work presented in the project report / dissertation is carried out by him / her, and that he / she has achieved the set objectives of the project / dissertation. Information derived from the published work of others has been acknowledged in the text and a list of references is given at the end of the report. I have personally checked this final report for originality / plagiarism through the Turnitin website and, to the best of my knowledge and belief, satisfied that the report is free from plagiarism.

Signature Date

Name

Countersigned by HoD

This project has helped me to expand my knowledge about clean energy sources and how to use them since it has been an area of interest for me since high school. It also helped me to relate between this field and my specialization in telecommunications engineering.

First of all, I would like to send my thanking prayers to Allah the whole mighty, first and foremost for helping me to complete this project successfully and within the needed time and blessing my time and effort. Furthermore, I would like to express my deepest appreciation to the project supervisor MR. Ali Almahruqi for his constant and ultimate help in support that guided me to complete the project successfully. Last but not least, special thanks to my family and friends whom I wouldn’t complete my work professionally without their endless support and prayers.

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As we live in a fast and growing world today, it’s the human’s responsibility to keep their planet safe and their environment clean not only for themselves, but for next generations as well. In this field of using renewable and clean sources of energy, a lot of devices and systems were developed using natural and clean sources to be used in different industries replacing the ones that harm the environment in any way with suitable ones. This project has included the design and implementation of a solar energy portable power supply that charges phones and other USB charged devices using photovoltaic (PV) solar cells. This project solved the problem of disconnection of power in phones or other small devices in any time or place, but using a clean source of energy that doesn’t harm the environment, supporting the idea of designing a practical and small size power supply using solar cells. This device works on capture and store methodology where it captures the energy from the sun and uses a storage battery for storing the absorbed energy for further usage and can be used at any spot that has good sunlight and can be used to charge for different times. It has another important feature which is charging wirelessly. The study includes a number of literature reviews showing same device already available with different techniques like capture, save, and charge method, as well as wireless charging capability. The design includes a set of shaped solar cells with specification in size length and width that can supply power of 5V, as well as a primary circuit with a DC converter, and a USB port, and a wireless charging model mainly. The results obtained from testing of the device showed that it works effectively in the time between 12-4 PM where the sun is perpendicular to the earth and solar cells can work better, and it takes 6-7 for the device to charge a phone till 60%, and 11-10 hours to fully charge a Smartphone. Future of such devices is very bright especially now days where people started to realize the importance of clean energy for the environment. In this project, the same method of capture and store is implemented with some modifications like the shape of solar cell and the wireless charging model used.

Key words

PV cells, USB port, DC converters, solar charger

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TABLE OF CONTENTS DECLARATION BY THE STUDENT i ACKNOWLEDGEMENT ii ABSTRACT iii TABLE OF CONTENTS iv LIST OF FIGURES vii LIST OF Table vii ABBREVIATIONS ix CHAPTER 1 INTRODUCTION 1 1.2 Project Objectives 2 1.3 Project Scope 3 1.4 Project Feasibility 3 1.5 Project Methodology 4 1.6 Project Challenges 4 1.7 System Features 5 1.8 Project Motivation 5 1.9 Report Structure 5 1.10 Summary 6 CHAPTER 2 LITERATURE REVIEW 7 2.1 Development of a solar Portable Power Charger for a Green Energy Initiative 7 2.2 Utilization of Battery Bank using Solar PV System in small devices 11 2.3 A battery powered and solar powered wireless sensor node 13 2.4 Solar-powered Phone Charger is as efficient as the Wall Phone Charger 16 2.5 Solar based mobile charger in rural areas 18 2.6 A solar mobile charger with a buck converter 20 2.7 Summary 22 CHAPTER 3 SYSTEM PRE DESIGN 24 3.1 System Block Diagram 24 3.2 Hardware Components 25 3.2.1 Photovoltaic Solar Cell 25 3.2.2 DC Converter 26 3.2.3 USB Hubs 26 3.2.4 Lithium-Battery 27 3.2.5 Switch 27 3.2.6 Voltage Regulator 28 3.2.7 LED 29 3.2.8 Wireless Charging Model 29 3.3 Flow Chart 30 3.4 Summary 31 CHAPTER 4 METHODOLOGY 32 4.1 Project Planning 32 4.2 Research Phase 33 4.3 Design Phase 34 4.4 Software Design 34 4.5 Hardware Design 34 4.6 Development Phase 35 4.7 Testing and Analysis Phase 35 4.8 Summary 35 CHAPTER 5 SYSTEM DESIGN AND IMPLEMENTATION 36 5.1 Software Implementation 36 5.3 Software Simulation Expectation 37 5.4 Hardware Implementation 40 5.5 Hardware Testing 42 5.5.1 Requirement Testing 43 5.5.2 Device Subsystems testing 44 5.5.3 Testing of the device 45 5.6 System Implementation in Printed Circuit Board (PCB) 46 5.7 Summary 46 CHAPTER 6 RESULTS AND DISCUSSIONS 54 6.1 Software Analysis 54 6.2 Hardware Analysis 55 6.3 comparisons between hardware and software results 56 6.4 comparisons between the result of the device and previous systems result 57 6.5 Summary 58 CHAPTER 7 CONCLUSION 59 CHAPTER 8 RECOMMENDATIONS/ FUTURE WORK 61 8.1 Recommendations 61 8.2 Future work 61 REFERENCE 62 GANTT CHART 64 APPENDIX I - FORMAL PROJECT PROPOSAL FORM 65 APPENDIX II-PROJECT RISK ASSESSMENT FORM 70 APPENDIX III-DATA SHEETS 73

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LIST OF FIGURES Figure 2.1 The Flow Chart Of The Power Supply. (Singh, Bhardwaj, Singh, 2014) 9 Figure 2.2 Arrangement Of The Direct Current And Circuit Implementation.(Pradhan, Ali, Puspapriyabehera, 2012) 12 Figure 2.3 The Sensor Node Circuit. (Fayeez, Gannapath & Mdisanorazyze, 2015) 14 Figure 2.4 Efficiency Of Solar Charger (Blue) Verses Wall Charger (Orange). (Cabrillos Et Al, 2013). 17 Figure 2.5 Block Diagram Of The Implemented Device. (Sudarshanreddy ,2014) 19 Figure 2.3 Block Diagram Of The Solar Power Charger (Theresa, Reba, Neetha, 2014)…………………………………………………………………………………………..21 Figure 3.1 System Block Diagram 24 Figure 3.2 Photovoltaic Solar Cell ………………………….……………………….……25 Figure 3.3 DC Converter 26 Figure 3.4 USB Hub……………………………………...………………………......……..26 Figure 3.5 Lithium Batteries……………………………………………………………......27 Figure 3.6 Switch 27 Figure 3.7 Voltage Regulator………………………………………………………………28 Figure 3.8 Led……………………………………………………………………………….29 Figure 3.9 Wireless Charging Model 29 Figure 4.1 Project Planning…………………………………………………………………33 Figure 5.1 Software Implementation of the Circuit Using Proteus Software (Part 1) 36 Figure 5.2 Software Implementation of the Circuit Using Proteus Software (Part 2) 37 Figure 5.3 When Voltage Is Low 38 Figure 5.4 When Voltage Is Medium 39 Figure 5.5 When Voltage Is Almost High 39 Figure 5.6 When Voltage Is High 40 Figure 5.7 Hardware Implementation 41 Figure 5.8 Device Subsystems 42 Figure 5.9 Subsystems Testing 44 Figure 5.10 Device Testing 45 Figure 5.11 Final Circuit after Implementation in PCB 46 Figure 6.1 Software Expected Result When Charging Level Is Low (Red LED)…….54 Figure 6.2 Software Expected Result When Voltage Level Is High (Green LED)……55 Figure 6.3 Hardware Result out Put 56 Figure 6.4 Solar Power Bank with Wireless Charge Model. 58

List of Figures

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Table 5.1 Testing Requirements Table …………………………………………………. 43

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PV- photovoltaic

USB- universal serial bus

LED- light emitting diode

PCB- printed circuit board

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As it is well known, we live in a fast growing world which became as small as a village because of the different communication methods and practical inventions in most of the fields which made life much easier and with fast rhythm. These methods and inventions on the other hand have its cons, not only for the human beings, but also for the planet that we live in, so it’s the human’s responsibility to keep their planet safe and their environment clean not only for themselves, but for next generations as well. In this field of using renewable and clean sources of energy that has less harmful effects on the environment and lead to less climate changes, a lot of studies were made related to this field like Singh, Bhardwaj,&Singh(2014) literatures that has been discussed in the literature review chapter explained about how to keep the planet alive simply, and reduce its main environmental problems such as pollution, climate changes, global warming, extinction of animals and plants, and a lot of more issues.

Additionally, a lot of devices and systems were developed using natural and clean sources to be used in different industries replacing the ones that harm the environment with suitable ones. Especially in power supplying fields, where the more the world develops, the more power is needed to be consumed in many areas. And since everything is computerized and digitalized now a days, people can do most of their activities online through their computers, smart phones, smart TV’s… etc. here comes the need of a fast and practical solution for the power disconnection problem that can be efficient, fast, reliable, and environmentally friendly for this problem, which comes in the form of power supplies uses solar cells which capture its power from the most important source of clean energy on the planet which is the sun.

There are a lot of existing power supplies depending on solar cells and photovoltaic cells for industrial and residential usages where for instance, china comes in the top of the countries that uses it and it produce around (22.5) MW of it total power production. As well as their high recommendations of using simple solar power supplies to charge laptops, phones, and other USB port charger devices, where Chinese educated their people about the importance of having a clean environment, even in some schools they started banding using electrical charges for phones or laptops and replaced it solar charging methods. On the other hand, such devices were good and efficient, but it has many limitations and gaps especially in the form of using wired methods to charge the devices with, and its expensive batteries used in these types of power supplies. However, on this part of the world, there was a need of a similar device used for the same mentioned purposes and filling the gaps of the already existing devices that work as power suppliers.

The idea of a portable solar power supply or (power bank) in simple words was proposed in this project aiming for solving the problem of the power disconnections where people can use this charger everywhere and at any time of the day to use their phones and laptops because as it is known everything is mobile based as its stated earlier. Also, having a small size portable device with high power intensity and good efficiency is truly bless especially for people who work outdoors and for long hours. Finally, make something that is humanely important but it does not harm Mother Nature at any kind or way. The next few pages will explain more about the device and its main objectives, the concept of working, methods used for implantation, feasibility of the project, problem description, challenges faced, and a scope of overall work has been done in this his project.

The main aim of the project is to design, implement, and test a solar power supply for charging different devices like smart phones and MP3 through two methods, either wired through a USB cable, or wireless through its wireless charging circuit.

1.1 Project Aim To design, implement, and test a solar power supply for charging different devices using two methods, either wired through a USB cable, or wireless through its wireless charging circuit.

· Study and review large amount of previous papers, studies, literatures and methods of popular power supplies used in the world currently and their working principle, and try to expand theoretical and practical knowledge on this field in order to successfully implement the design with no failures.

· Design a portable power supply with specifications like wireless charging ability, small pocket size device using solar cells technology to charge phones and other small devices that gets charged with USB ports.

· Software implementation of the device circuit using Proteus program.

· Hardware implementation of the device using the required components.

· Testing the solar power bank after charging the solar cells.

· Analysis of the results obtained from testing the solar power bank

This project has considered proposing a simple solution and some pros for most of the limitations like high power consumption, high feasibility, heavy weight, and time consuming. The solution depends basically on using the solar cells that solves almost everything related to reducing power consumption, reducing feasibility, and reducing environmental friendly and light weight sides.

The main concept of the project is built on having basic knowledge about electrical circuits connections and hardware components used in the project, as well as some brief background about how the solar cells usual work and what’s the strength and weaknesses of these components. So it can critically analyzed and give correct result and analysis and conclusion section in the project. Then comes the software implementation part that starts with having a primary circuit of the project will be drawn used Proteus software and getting the simulation for the wanted output. Finally, the hardware implementation and testing phase that should be done successfully to find the correct results and achieve the wanted goal aimed for.

All of the hardware and software components used to implement this device are locally available inside the country which helps to cut the expenses of cargo and importing it from outside. Additionally, the implementation of the software simulation circuit and design is done using Proteus software which is available and easy to approach and costly affective. Finally, the literature reviews like journals, articles, and books used in this project are available online through internet browsers and using different search engines or via college library books which are available, feasible and affordable for everyone.

As it was stated earlier in the project scope, the device will be carried out using the following steps first of all expand knowledge and read more about the solar cells and the primary circuit component specially the PV solar cells used in the system and read more literature reviews about this part, focusing on weakness and strength points, as well as read about the wireless and wired charging methods now and then , additional to read about the USB port devices and the amount of power needed to charge through them. Based on these studies the device will be implemented with the software stage first, then the hardware phase secondly, and based on this the result and analysis will be stated and proper conclusion and recommendations of the operation will be given.

As any other technical project, this project is expected to have some few challenges in implementation and designing phase, for instance, the PV solar cells must be connected in a special pattern in such devices , as well as connecting the hardware components itself is a time consuming operation which must be done before the beginning of the semester. Also, the testing phase is expected to have one extra challenge since the solar cell only can work on the day light, so testing it in the afternoon or at night is not possible. Most of these challenges can be avoided by working on the project due the given time, meet the deadlines and achieve the outcomes and objectives expected from this project.

The solar power supply will have features like having two methods of charging either by wireless charging circuit or wired via USB output port. Also, the power supply will be in the size of the pocket which makes is easy to carry around. Finally, it will have a set of LEDs to show the level of charging and notify the user when the device is fully charged.

The idea of the project has come up due to the problem of powered off devices always in the roads or outdoor places and disconnection of devices because of low charge battery, so solving this problem as an engineering included using previous knowledge in environmental science and basics of electrical circuitries to design and implement the mentioned device to be used in many sectors not only telecommunication devices. This will give the opportunity to implement the theoretical knowledge has been gained in a practical way, as well as helping to improve other skills like critically analysis, problem solving and time management.

The report consists of 8 chapters starting with introduction which is the first chapter; it contains aim and objectives of the project, problem to be solved by the project, feasibility of project, project scope and methodology, motivation and challenges of the project. The second chapter which is literature review chapter and it includes previous studies and cases similar to the project. Then, the 3rd, 4th, 5thchapter which contains the methodology and experimental setup of the device in terms of software, hardware implementation and its core components and working criteria. Then, the 6thchapterthat includes results and analysis of the output of the device. Finally, 7thchapter which has the conclusion and 8thchapter which has the recommendations and future work that can be implemented to improve such devices.

To sum up with, this chapter explains the main concept of the project and how it’s designed and how it should be carried out eventually, giving the reader the basic understanding of the project and its flow. It also explains the methodology of making the solar power supply starting from software implementation in Proteus program, then hardware implementation of the components that will be stated later, finally test the device and analyze the output of the device.

Chapter 1 Introduction

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Overview

This is the second chapter in the report which represents the previous literatures about the solar energy and its usage in general, and power supplies based on this system specifically. The previous literatures and studies represent a very important source for expanding fundamental knowledge and positively contribute in the final execution of the project itself by working as a main guide for implementing the project. Most of the studies and literatures that have been used in this chapter are related articles and journals to the same field of the project.

Singh, Bhardwaj, & Singh (2014) they presented in their paper the design and the development of a solar Portable Power Charger for A Green Energy Initiative. In their paper, they stated that the main aim of this device is to have a small size, cheap, available, and modern power supply that uses one of biggest sources of the clean energy that we are blessed with which is solar radiations from the sun. As well as solving battery charging problem in an easy and efficient way, since charging phones and other smart devices is a must nowadays because most of the things people do in their lives are through phones or computers. And running out of power is a headache people want to avoid. Additionally, work on inventing an environmentally friendly device that depends on clean powering and does not affect the environment in any way. The authors presented an easy and sufficient plan to implement this power bank in minimum time to help people avoid or reduce the problem of power disconnections due to low batteries. The authors also reviewed the previous studies and methodologies have been introduced related to this field in previous recent years and they explained how these studies are important and relevant to their work, and supported and proved that with a number of statistics about the usage of solar cells in the powering field recently (Singh, Bhardwaj, Singh, 2014).

The implementation of the proposed device involved the method of using flexible hardware and software components which gave it a lot of abilities unlike normal devices in this field. The hardware requirement includes PV solar cells, as well as wind module adapters, USB module, LCD display, PIC8f452 microcontroller(op-amp), DC-DC boost converter, li-ion battery( 2000mAh,3.7V). While software components are powers (PSIM), and micro CPRO for PIC (Singh, Bhardwaj, Singh, 2014).

The implementation of the device depended on capture+ store+ charge , where the device parts was practically implemented inside the campus by placing the hardware components as the circuit shows, and put the solar cell to charge for 3-5 hours to get the wanted result (Singh, Bhardwaj, Singh, 2014).

Then the result derived from the implementation was that the device affectively works faster during mid-time of the day (12-4) pm, and that it stores the energy faster at that time (Singh, Bhardwaj, Singh, 2014).

These authors successfully presented an effective and efficient device that supplies the needed power to keep a device alive using solar energy.

Figure 2.1 The Flow Chart Of The Power Supply. (Singh, Bhardwaj, Singh, 2014)

Figure 2.1 shows the flow chart of the power supply taken from authors (Singh, Bhardwaj, Singh, 2014) which was explaining the methodology authors adopted to explain how their device is going to work to overcome the problems has been stated earlier. The flow chart begins with start of phenomena of capturing the power from the main source which is the sun, and they had another option of a wind source usage of a wall plug adapter device which works for the same purpose in case the sun is not sufficient in some areas or the sun energy is less then wind energy. Then the chart contains storage of energy from one of the previous sources in a li-ion battery, and then sends the stored energy to a DC-DC boost convertor which sends the power directly to the USB output port. Then the end shape of operation which tells that the end of this procedure is over.(Singh, Bhardwaj, Singh, 2014)

The proposed device mainly consists from PV solar cells, a microcontroller PIC18f452 block, DC boost converter, and a li-ion battery. The system works as following; the PV solar cells are used as one source of energy, and this energy is applied to the DC boost converter to set up the input voltage of the PV cell to be sufficient for the USB wanted output. Then, the USB port can be used for the purpose of charging any type of devices. Moreover, the PV cell can stop its USB voltage level that is equal to 5V; due to small amount of power level provided which makes the device limited. Additionally, the PV cells energy is sent to dc-dc boost converter along with li-ion battery to supply enough power and voltage to the USB port. Therefore, the required energy is ready for the portable device to charge its battery. (Singh, Bhardwaj, Singh, 2014)

The main difficulties that the authors faced as they stated was “having some small gaps in implementing the practical phenomena of capture, store, and charge in some areas, where it’s all depending on the amount of sun the device can capture in that area, as well as the efficiency of the PV cells used where it works with different capabilities.” (Singh, Bhardwaj, Singh, 2014)

Though the device is good and highly recommended to use, but it has some limitations such as its wired, which means that the use will always need wiring to charge and thus the wireless charging technology can be added to the device, also the journal missed some main technical aspects like the detailed methodology of how it works and the future applications can be derived from this system. (Singh, Bhardwaj, Singh, 2014)

For the author point of view, the device would be improved by using a nickel-cadmium (NiCad) battery due to its ability of rapid charging and fast absorption of the needed power more than the li-ion battery, as well as its ability to live linger because it doesn’t get affected by the environmental changes and has less aging ability. Also, it can use an MSP430 microcontroller due to its easy configurations and programming abilities.

To conclude with, using the natural sources of energy that this planet is blessed with is the main purpose of this project. The proposed system of the device was highly useful, with significant features like high performance in supplying the needed power, environmentally friendly, economical and has an affordable coast the results of this device was quite good compared to other devices in the same field where it has the ability to be powered wither from the sun or by wind power which made it more efficient, as well as not harming the environment in any way. And this device can be used to charge several electronics gadgets such as mobile phones, Mp3 players, etc.

Pradhan, Ali &PuspapriyaBehera (2012). These authors presented in there paper Utilization of Battery Bank using Solar PV System in small devices that has less power conception, And some Classification of Various Storage Batteries. They have stated that the main aim of this proposal is to make a battery bank utilized and using Solar PV system and also gives an idea about various types of batteries and their comparison. As well as reducing the usage of electrical batteries that harmfully effect on the environment. Moreover, give sub solutions for charging small electrically powered system faster and more affectively especially for regions located near the earth equator .The authors used some of the previous studies related to this field in previous recent years and they explained how these studies are important and relevant to their work. (Pradhan, Ali, PuspapriyaBehera, 2012)

The implementation of the device included the following hardware components PV modules, DC interface and regulation device, power supply, meter, power conditioner, solar module adapter, and a battery bank. While it did not have any mentioned software components or programs. Additionally, the method they used to implement their system is connecting the PV module shaped in a rectangular way to the DC interface and regulator, then to the battery bank. And the other PV module is connected to a power conditioner then send to a meter that measure the power absorbed by the PV modules. Finally, connect the output from this connection to a load that sends the absorbed power to the needed device. (Pradhan, Ali, PuspapriyaBehera, 2012)

The result derived from this system was that batteries perform the following function on a PV system firstly, dependence–by meeting the load requirements at all times, including the night times, during overcast periods, or during the winter when PV input is low or deficient. Secondly, offer current capability and it’s done by supplying when needed currents higher than the PV array can deliver, especially to start motors or other inductive equipment. These authors productively presented an effective and efficient device used to generate power for small devices such as fridges or freezers.(Pradhan, Ali, PuspapriyaBehera, 2012)

Figure 2.2 Arrangement Of The Direct Current And Circuit Implementation.(Pradhan, Ali, Puspapriyabehera, 2012)

Figure 2.2 above illustrates the arrangements for a direct current off-grid, and an alternating current grid- connected for a residential PV system, and as stated earlier, the implementation was done by connecting the PV module shaped in a rectangular way to the DC interface and regulator, then to the battery bank. And the other PV module is connected to a power conditioner then send to a meter that measure the power absorbed by the PV modules. Finally, connect the output from this connection to a load that sends the absorbed power to the needed device. (Pradhan, Ali, PuspapriyaBehera, 2012)

Moving on the difficulties faced by authors while implanting there device which is summarized as following first of all, continuous discharge of the battery which is due to high temperature or over using at a time. Secondly, the power conditioner and the PV module were financially expensive.(Pradhan, Ali, PuspapriyaBehera, 2012)

Additionally, the device implemented was efficient and fast, but has a limitation which is instability, which means it can disconnect if any problem appeared in the battery bank or the power conditioner, which can limit its performance.(Pradhan, Ali, PuspapriyaBehera, 2012)

In the author point of view, the system proposed in this literature can be developed by increase the size of the battery bank or put two banks; in case one is not working the other can work efficiently. Also, add a feature of making the PV module movable automatically with the direction of the sun, to absorb more radiation.

To sum up, the proposed system of the device was useful, with features like good performance in supplying the needed power for small systems, environmentally friendly, economical and affordable. Also, energy created by PV system and stores it will be used at night or when there is no other energy input which gives this system one more positive feature.

Fayeez, Gannapath&MdIsaNorAzyze (2015). In this literature, authors discussed about a battery powered and solar powered wireless sensor node. The authors mentioned that the aim of the literature done is to compare the use of solar cells verses normal batteries for powering the wireless sensor node, in terms of quality, ability, characteristics of charging, and capacity or volume. As well as knowing the usage of solar cells in the powering field nowadays. Additionally, the authors reviewed and displayed the previous studies related to this field in previous years and they explained how these studies are important and relevant to their work, and supported and proved that with a number of graphs and circuit diagrams about the solar cells in the powering field recently. (Fayeez,Gannapath, MdIsaNorAzyze, 2015)

The actual implementation of the wireless node consists from hardware components as well as internet access. Hardware components include sensor, power supply, memory, and controller. And they have stated that internet access must be there to examine the working of sensor.(Fayeez, Gannapath & Mdisanorazyze, 2015)

The implementation of the device was done by connecting the architecture of the wireless sensor node to the two types of power supply sources, a normal battery and a solar PV cell. The architecture of the node consists from the communication block, connected to the controller block, and the controller then connected to memory, then the output of this connection was connected to the two power supply sources each at a time, to discover which is the best, and finally power goes to the sensor. (Fayeez, Gannapath & Mdisanorazyze, 2015)

The result that is derived from this implantation was that both types of power supply is effective, the PV cells takes longer time to charge but it stays for longer period of times, and the electrical batteries stay for shorter time and cheaper. The authors agreed that people should use more of clean energy sources and less electrical sources of energy. They have shown an effective methods to charge the wireless node and in a sufficient way. (Fayeez, Gannapath & Mdisanorazyze, 2015)

Figure 2.3 The Sensor Node Circuit. (Fayeez, Gannapath & Mdisanorazyze, 2015)

Figure 2.3 above shows the sensing block which includes one or more sensors. Analogue processing matches the sensor output to the digital processor usually and uses a lower cost microcontroller and commercial transceivers also are used for wireless communication. Meanwhile, the power supply has to be provided to the different stages as the graph shows and it was changed from electrical to PV solar cells.(Fayeez, Gannapath & Mdisanorazyze, 2015)

Moving on to the main difficulty the authors faced while implantation of their experiment which was the lake of time, where they had to finish their experiment due specific date, but otherwise everything was good.(Fayeez, Gannapath & Mdisanorazyze, 2015)

The authors presented a small comparison of the advantages and disadvantages of each battery source which is summarized as following

Rechargeable battery the pros is the Cost is paid back quickly for high utilization applications which Increase economic and environmental benefits, and the cons is Cost of charger - for low cost applications the charger can cost much more than the actual product Lower energy density overcharging can damaging the battery. (Fayeez,Gannapath & MdIsaNorAzyze, 2015)

Solar cells pros that solar power not only be used for outdoor applications, but can be used for indoor applications since Solar energy does not cause pollution. Low electricity bills unlimited supply of solar batteries can use storage device to storage the energy, and the cons are High Cost Require a battery charge, to use solar power at night. (Fayeez, Gannapath & Mdisanorazyze, 2015)

The experiment done was good and shows the affectivity of the solar cells in power supplying in such systems, but it has some gaps or limitations such as not enough explanation of the wireless sensor node circuit and how it was connected, as well as the type of battery used as electrically charging source. (Fayeez, Gannapath & Mdisanorazyze, 2015)

For Author point of view, the experiment done on the device would be improved by always using a nickel-cadmium battery along with the solar cells due to its ability of fast charging and fast absorption of the needed power more than the other types of battery.

As a conclusion, the highest power density from the solar cells is the best alternative that will provide the best option in terms of size and weight. So, for power density of solar cells powered mainly depends on size, manufacturer and also type of cells technology used. Meanwhile, the solar cell powered has constantly increasing usage in this area and still predicted to have a brighter future. (Fayeez, Gannapath & Mdisanorazyze, 2015)

Cabrillos et al. (2013). The title of the literature was “ Solar-powered Phone Charger is as efficient as the Wall Phone Charger “, where it discussed about how a solar charger of phones can be as effective as a normal wall electrical charger. The authors presented in their research a simple and easy design of the implementation of this device and a small comparison between wall charger and solar charger. They have also stated that the aim of this device is to proof the efficiency of solar charger and examine its advantages which as they said is more than its advantages and way better than a wall electrical charger. The authors also displayed and discussed the previous literatures in this field in previous years and they explained how these studies are important and relevant to their work, and proved that with a number of literature attached to their work. (Cabrillos et al, 2013).

The implementation of the device after finishing its hardware connections includes two parts, first part was the efficiency test and second part was the calculation for the time in which batteries will be completely charged. In efficiency test, currents and voltages were measured for the output side of the chargers. The test for the solar charger was conducted with a direct sunlight and with a shade to compare the output power. The test for solar charger was conducted in four trials with a time gap of one hour starting at 11 o’clock in the morning. The test for the wall charger was also conducted at the same time. The test was replicated four times to determine its average power. (Cabrillos et al, 2013).

Then the result derived from the implementation was that the solar charger under direct light gives off a larger current than the solar charger under indirect light that just only gives an average of 752.25 mA. Also, the output voltage for the solar charger placed directly into sunlight has a higher value with 5.43 V compared with the solar charger under indirect sunlight that just only has 5.33 V value. The wall charger has a high output current of 957 mA but a low output voltage of only 4.88 V. additionally, these authors successfully presented an effective and efficient device that works with solar clean energy and proofed it can be as good as an electrical charger or even better. (Cabrillos et al, 2013).

Figure 2.4 Efficiency Of Solar Charger (Blue) Verses Wall Charger (Orange). (Cabrillos Et Al, 2013).

Figure 2.4 shows the Efficiency of the solar charger (blue) and the wall charger (orange), where it shows the linear relationship between the output and the input power of a solar charger and wall charger. It also shows that solar charger can have almost as same efficiency as the wall charger the difference between them is only 5 %.(Cabrillos et al, 2013).

The main difficulties the authors mentioned that the while testing the solar device, the sun was not as strong as they expected it to be, because it was during spring and the sun is not perpendicular. Also, a lot of calculations were done which made the result and analysis longer. (Cabrillos et al, 2013).

Though the device has good efficiency, and highly recommended to use, but it has some limitations such as its ability to work only under direct sunlight, and makes it hard to use in countries with less or no enough sun radiations.(Cabrillos et al, 2013).

In a personal point of view, the device would be improved by adding a wireless feature so that it can charge with no wires, as well as use square shaped solar cells for more absorption.

To conclude with, the findings of this research indicate a positive response that solar-powered charger is as efficient as a wall charger, and the portable solar-powered phone charger is indeed as efficient as the wall phone charger. While the use of the wall charger takes only 2hours to charge the same battery. (Cabrillos et al, 2013).

sudarshanreddy (2014). The title of this literature was “solar based mobile charger in rural areas”, were it contained a small explanation about how to implement a solar power supply for mobile phones specifically, and used in rural areas precisely. The author displayed his method of implanting such device. And he stated that how beneficial it is for on road people or people who work in rural areas with no place for electrically charge their phones through a wall charger, which represent the aim of his project. The author also discussed the previous literatures related to his project and where he god the inspiration from. And he added some Figure is showing his implantation method. (sudarshanreddy ,2014).

The implementation of his device was as following A normal PN junction diode is used for unidirectional flow of charge current and connected to the cell, then connected to the DC converter, and finally to the device. The output of the solar Cell depends on the intensity of the solar light. A rechargeable battery, storage battery, secondary battery or accumulator is a type of electrical battery can be used, and the regulator circuit is designed to get a fixed voltage of 5v. (sudarshanreddy ,2014).

Then the result derived from the implementation was that the device affectively works faster when the light intensity is higher. And the device was working effectively as planned. (sudarshanreddy ,2014).

Figure 2.5 Block Diagram Of The Implemented Device. (Sudarshanreddy, 2014).

The Figure 2.5 above shows the block diagram of how the circuit of this device will be implemented where, the solar Cell is connected to the current control device, then to the rechargeable battery through wires, then energy is sent to power supply, where it sends it to the microcontroller, relay, multi charger pins, finally to the mobile phone. (sudarshanreddy ,2014).

The only difficulty the author faced was programming the microcontroller used where it was complicated and time consuming. (sudarshanreddy ,2014).

The device was good and affective to use, especially in rural areas, but it has few limitations like no specific battery was used, where the author used more than one battery without referring to them with much information. And also, the microcontroller used was difficult to deal with and unnecessary for such simple implementation (sudarshanreddy, 2014).

For author point of view, the device would be improved by using a simpler circuitry, and replace the multi charging pins with a normal USB hub for a simpler and faster connection, as well as eliminate the usage of relays because it fasters the aging of the electrical circuit in simple devices as given.

To conclude with, the output from this proposal for such devices was to replace electrical power supplies with other clean sources for energy as given in this paper. And the author proved that sola charges are affective as well and people can depend on (sudarshanreddy, 2014).

Theresa, Reba, &Neetha (2015) provided in their journal an actual implementation and a study about a solar mobile charger with a buck converter. In their paper, they have mentioned that the aim of this charger is to have a device that can be used in travelling and easy to carry around, as well as its environmental positive impact compared to other similar devices. Also, its constant input and output voltage that increase its efficiency. The authors explained a clear method of implementing this device to achieve the aim mentioned earlier. Moreover, the authors reviewed the oldest literatures in this field and stated how it’s related to their work, and added some graphs and charts supporting this work (Theresa, reba, neetha, 2014).

The implementation of this device contained hardware components like 12v solar Cell, linear regulator, processor, buck converter, PIC microcontroller, and battery. On the other hand no software program was mentioned. Furthermore, the method used by the authors to implement their device was connecting the solar cells that convert solar energy to electrical to the converter, which then step down the voltage input. Then the buck converter is connected to convert the output voltage to the wanted value. Then the output is sent to the PIC microcontroller to produce higher PWM. Then the final output charges the wanted device (Theresa, reba, neetha, 2014).

The result obtained after implementation of this device was that the maximum solar power falls on the surface of the earth at middle f the day gives maximum output voltage to use in the device. These authors effectively presented efficient device used to charge mobile phones and portable with light weight (Theresa, reba, neetha, 2014).

Figure 2.3 Block Diagram Of The Solar Power Charger (Theresa, Reba, Neetha, 2014).

Figure 2.3 above shows the arrangements for the block diagram of the solar charger, where the solar Cell and the power supply was connected to the buck converter ( buck charger controller) , then to battery, and finally to the device (Theresa, reba, neetha, 2014).

Moving on the difficulties faced by authors while implementing there device which is summarized as following first of all, the rareness of the wanted microcontroller and its high coast. Secondly, the experimentation of the device was made three times and in two levels to achieve the correct wanted working criteria which were time consuming (Theresa, reba, neetha, 2014).

The previous mentioned device was very efficient and practical to use due to its high output power and light weight, but it has few drawbacks such as the short life time of the buck converter, as well as the lake of information provided in the research about this device and its working criteria (Theresa, reba, neetha, 2014).

In the author point of view, the device would be improved by using PV solar cells which can be more effective in such devices due to its high absorbance of sunlight during the different time of the day, as well as use more resistors to protect the components from damage. Also, use a MOSFET switch to generate continuous voltage at the output.

To conclude with, the output from this proposal of such devices was to support and confirm that solar mobile chargers can be a better and cheaper option for charging the phone to normal electrical phone charger (Theresa, reba, neetha, 2014).

As it was stated earlier, previous literatures are important source of knowledge and experience in the wanted field, where it gives a general overview about the work has been done in the same field of the presented project. As well as knowing the procedures other people did and the gaps were made. Now, representing a small brief about each of the literatures as following;

Singh, Bhardwaj & Singh (2014) aimed to have a small size, cheap, available, and modern power supply that uses one of biggest sources of the clean energy. The result derived from the implementation was that the device affectively works faster during mid-time of the day (12-4) pm, and that it stores the energy faster at that time. These authors successfully presented an effective and efficient device that supplies the needed power to keep a device alive using solar energy.(Singh, Bhardwaj, Singh, 2014)

Pradhan, Ali &PuspapriyaBehera (2012) Aimed to make a battery bank utilized and using Solar PV system and also gives an idea about various types of batteries and their comparison. The Result derived from this system was that batteries perform the following function on a PV system. firstly, dependence–by meeting the load requirements at all times, including the night times, during overcast periods, or during the winter when PV input is low or deficient.These authors productively presented an effective and efficient device used to generate power for small devices such as fridges or freezers.(Pradhan, Ali, PuspapriyaBehera, 2012)

Fayeez, Gannapath & Mdisanorazyze (2015) aimed to compare the use of solar cells verses normal batteries for powering the wireless sensor node, in terms of quality, ability, characteristics of charging, and capacity or volume. The result that is derived from this implantation was that both types of power supply is effective, the PV cells takes longer time to charge but it stays for longer period of times, and the electrical batteries stay for shorter time and cheaper. The authors agreed that people should use more of clean energy sources and less electrical sources of energy. They have shown an effective methods to charge the wireless node and in a sufficient way. (Fayeez,Gannapath and MdIsaNorAzyze, 2015)

Cabrillos et al. (2013) aimed for this device is to proof the efficiency of solar charger and examine its advantages which as they said is more than its advantages and way better than a wall electrical charger. The Result derived from the implementation was that the solar charger under direct light gives off a larger current than the solar charger under indirect light that just only gives an average of 752.25 mA. Also, the output voltage for the solar charger placed directly into sunlight has a higher value with 5.43 V compared with the solar charger under indirect sunlight that just only has 5.33 V value.These authors successfully presented an effective and efficient device that works with solar clean energy and proofed it can be as good as an electrical charger or even better. (Cabrillo’s, 2013)

sudarshanreddy, (2014). Stated that this device is Beneficial for on road people or people who work in rural areas with no place for electrically charge their phones through a wall charger, which represent the aim of his project. The Result derived from the implementation was that the device affectively works faster when the light intensity is higher. And the device was working effectively as planned. (sudarshanreddy, 2014).

Theresa, Reba, &Neetha (2015) provided in their journal an actual implementation and a study about a solar mobile charger with a buck converter. In their paper, they have mentioned that the aim of this charger is to have a device that can be used in travelling and easy to carry around, as well as its environmental positive impact compared to other similar devices. Also, its constant input and output voltage increase its efficiency. The authors explained a clear method of implementing this device to achieve the aim mentioned earlier (Theresa, reba, neetha, 2014).

All of the previous literatures are related to this project either in its working methodology, hardware components, or its circuitry implementations. However, the most related literature to this project is the first one Singh, Bhardwaj, & Singh (2014) .The project uses almost the same concept for charging the cell phones, as well as other USB charged devices and the same components, the difference is in the power storage battery, and the implementation methodology. Thus, more features will be considered to be added to the project next semester and the proper modifications will be stated in the final report.

Chapter 2 Literature Review

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Overview

System pre design explains block diagram that represents how the parts of the device will be connected and gives a brief explanation about how every subsystem is connected to the other to make the final system works effectively. Also, will explain Hardware requirements and a small brief about it and how it’s used in the device and the flow chart of the device in its final phase with a miner explanation on it.

Figure 3.1 System Block Diagram

This system block diagram shows the main blocks which represent the parts and the connection of this device, where by the main block in this device is the solar Cell. This solar Cell block is connected to the IC charger block that works as a connector between the solar Cell block and the lithium battery block in order to store the energy for later usage. Moving on to the next important block of this device which is the wireless charging model, this block enables the wireless charging ability if the wired charging method is not used. Moreover, the USB blocks transfers the power from the source to destination that must be charged if the normal wired method is used.

Figure 3.2 Photovoltaic Solar Cell

These are devices that basically produce electric energy directly from the sun radiation through electronic operations that appears naturally in some type of materials known as semiconductors. Physically, electrons inside these materials are freed by the energy radiations from the sun, and can transfer through electrical circuits, and send the electrical power to the wanted grids. (Electronics for you, 2012) Typical PV Cell absorbs the sunlight and convert it into electrical power. It can be placed ground, on mountains, or even used in electrical devices. In this device, the PV solar Cell used has 5V and 1W output capability making it suitable for such device usage. Also it has a diameter of 8cm and a square shaped.

Figure 3.3 DC Converter

This is an electronic component that basically converts the direct current source from a level of voltage to another. Also known as a device of electrical power converting, its power levels are between very low and very high, which make it usable for almost most of the circuitries.(Electronics for you, 2012) The type of DC converter type used in this device is buck-converter because the input to the device is 5 V and it gives output of 3.3 V to protect the rest of the components from burning or damage.

Figure 3.4 USB Hub

They are electrical simple devices that expand one universal serial bus ports into many ones, which give ability for more devices to be connected at the same time to the same host. And it’s working is similar to a power strip. They are usually used in monitors, keyboards, and computers. (Electronics for you, 2012)This USB used in this device to transfer the energy from source to destination through a USB cable, and is and it has source and destination ends.

Figure 3.5 Lithium Batteries

Figure 3.6 Switch

Figure 3.7 Voltage Regulator

Figure 3.8 Led

 Light-emitting diode (LED) is an electronic light source with two ends, positive (anode) and negative (cathode). It emits light when activated by applying a reasonable amount of voltage. It toggles to show the status of voltage and the color of light is determined by the energy band gap of the same semiconductor. (Wikipedia, 2011) In this project, LEDs are connected and controlled by voltage regulator, where it shows the status of voltage and power of device.

Figure 3.9 Wireless Charging Model

Wireless charging model is an electrical component consists from two parts, a transmitter and a receiver. It uses electromagnetic field to transfer the power from transmitter to receiver using electromagnetic induction. It is made from good conducting materials in general but mostly copper.(Electro Schematics, 2011) In this device, the wireless charging model transmitter is connected to the power bank, and the receiver is outside the circuit and can be connected to the device that need to be charged.

Figure 3.10 System Flowchart

This Figure shows the systems flow chart, where it shows the steps of working and process\steps of the device. First of all, the PV solar Cell absorbs the energy from the sun, and then it sends it to the storing battery (lithium batteries). Then the battery stores the energy for further use. Depending on the charging method, the energy will be distributed. If it used the wired charging methodology, the energy will be sent to DC converter and USB output port, if it used the wireless charging methodology, wired method will be disabled and the wireless charging circuit transmitter and receiver will work.

This chapter included the system of the device and criteria, where it includes the block diagram and its explanations, and its main blocks that is used in this device, hardware requirements and a small brief about it and how it’s used in the device, and the flow chart of the device in its final phase with a miner explanation on it.

Chapter 3 System Pre Design

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Overview

This chapter will represent the methodology used in this project, and explains the steps has been follow to successfully complete this project starting from choosing the idea of the project until its last step which is hardware implementation and testing. Moreover, it will include project planning phase, research phase, designing phase, software and hardware designing phase, development phase, result phase, and a chapter summery.

In order to do a project effectively and efficiently, a basic plan of the project must be done in order to perform aims and objectives from the project in the right way and time. This has been followed in the case of this specific project where by the following steps was done to get to the final phase of the work. The first thing is choose the project idea and get the approval from project committees. Secondly, read about the project and expand theoretical and practical knowledge by reading previous literature and analyze it. Thirdly, identify the requirements needed for this project in terms of software, hardware and other requirements. Fourthly, give a small costing explanation to show the feasibility of the project. Then comes the design of the project in its different phases which also includes hardware, software design. Finally, the implementation of the project will be carried and testing its working ability for recording results and analyze them.

Figure 4.1 Project Planning

This phase includes a primary and essential phase of project methodology; where by the knowledge about the project has been expanded by reading and analyzing from different sources like books, journals, websites, and previous literatures and paper related to the project. The research process helped in realizing the objectives and benefits from doing such project and recognizing the limitations of the current available devices similar to the one that will be implemented here. Moreover, this phase gave a clear overview about the requirements needed for this project whether it was a software program to make the circuit of the project, or hardware components used in the physical implementation of the device. For instance, a clear idea about the type of solar Cell used in the power banks of such abilities was taken, and the limitations of the solar cells in terms of storage ability and voltage-current toleration ability. Moreover, and based on the researches that have been reviewed, the following limitations were noticed

· Short lifetime of the device due to the type of solar cells used.

· Type of storage batteries used to store the energy from the sun.

· Types of wireless charging sender and receiver models.

The review was based on analysis of previous literatures as mentioned earlier, and the aim, objectives, scope were extracted. Also, the type of software was determined as well as specifications of hardware components.

This phase includes the device block diagram that explains how the connection of blocks representing the components was made. Then the components and subsystems that helped making the device, and the specifications and parameters of these components and how they are connected. Then the software and hardware design of the system. The basic software of the system was done with Proteus software program and with the help of the literatures that has been reviewed to extract the ideas from; as well hardware implementation which will give a clear idea about the connection and method of working of the hardware’s used in this device.

The software design of the circuit used in this project was drawn using Proteus software program which is electronic design automation software that is used for electronic and electrical circuit schemes, PCB layout, and simulation applications. It has been chosen to draw the circuit with due to its easiness of understanding and direct instructions of use. The used software give the circuit good abilities like changing the type of components used or renaming it according to the users need. It is also designed to show the circuits that contain LEDs by blinking to show if the connection is right.

Hardware design includes the components that has been used and connected together to give the needed output for this device, where by the specifications has been noted from the previous literatures with modification that suits the device used here. It included electrical different components and the main thing which is the solar Cell. More explanation will be included in the next chapters

This phase shows that based on the software design of the circuit of the portable power supply, the hardware components were connected successfully to give the desired output. The problem faced in hardware circuit was burned component due to heat and over use, and it has been fixed by changing the switch.

This phase included a very important part of the project, where the testing was done for the hardware components and the subsystems (sub circuits) to proof its efficiency and working ability. Then the output from hardware implementation was analyzed and explained with details, Figure s, statistics, and numbers. And the output has been noted after testing the device and recognizing its weakness and strengths areas. Also, a comparison between the output of this device and the output of other device in one of the literatures has been reviewed to recognize weakness and strength points.

This chapter has included the methodology used to complete the device used in this project and its main steps, as well as stating the phases that the project went through starting from choosing the topic till analysis of results.

Chapter 4 Methodology

Overview

The implementation phases of the given device started with understanding the flow chart and block diagram that explains the flow of the device working criteria as shown before in the third chapter, then comes the software and hardware implementation phases. Software implementation includes drawing the circuit in the Proteus software and dividing the circuit into three main sub circuits which will be explained later and showing the expected output from the hardware circuit. Moving on to the hardware phase which will include the physical implementation of the components of the device and how they are connected.

The software circuit of the device was drawn using Proteus software, in order to modify the circuit easily and add\ remove features to the circuit, since this software is easy to do these functions with.

Figure 5.1 Software Implementation of the Circuit Using Proteus Software (Part 1)

Figure 5.2 Software Implementation of the Circuit Using Proteus Software (Part 2)

As the previous Figure shows, the device contains three circuits that represent connection of the components, where all of the circuits are connected together. First sub circuit represents the circuit that measures the percentage of the device charging, where the IC KA2284 voltage level indicator is connected in series with the LEDS pins and in parallel with four LEDs pin and 2 resistors of 100 ohms, and 10K, Then connected to 220UF capacitors. This is then connected to resistance regulator. This circuit is connected to the solar Cell then solar Cell is the connected to the lithium battery in its both positive and negative terminals. The second circuit that controls the output voltage from the circuit to the desired device and has the USB output port that carries the voltage to the destination devices through USB cable. Finally the third circuit that controls the wireless charging, where two coils are connected one as Tx and one as Rx as the Figure shows, the receiver is connected to LED to show its working ability.

Since this device is not connected to any kind of microcontrollers, there is no simulation output, but expected output from this device has been predicted by drawing colors of toggle ling LEDs in the software circuit. Software circuit implementation showed the expected status of the voltage inside the device must be charged and when it’s fully charge. Each state shows the amount of voltage or the charging level, the red LED shows that the voltage level is low and the device battery is almost empty (less than 25 %), the yellow LED shows the average or medium voltage (25-50%), the white LED shows that the charge level is almost finished (75%) and the green LED shows that the voltage is high and the device is charged successfully (90-100%).

Figure 5.3 When Voltage Is Low

Figure 5.4 When Voltage Is Medium

Figure 5.5 When Voltage Is Almost High

Figure 5.6 When Voltage Is High

Hardware implementation of the device was done using major components that has been stated earlier like solar cells, transmitter and receiving wireless charging model, USB output port and other components. This section contains the connection of components and how each circuit is connected to others, and also the testing of the device which made several times to get the desired output.

Figure 5.7 Hardware Implementation

The Figure above shows the hardware implementation of the device. This connection based on the software circuit output. The circuit has three main parts represents the subsystems, first circuit represents the circuit that measures the percentage of the device charging, where the IC KA2284 voltage level indicator is connected in series with the LEDS pins red, yellow, white, and green to show the voltage status, and 2 resistors of 10K, and 100 ohms to protect the circuit from the damage. Then this part is connected to 220UF capacitors. This is then connected to resistance regulator, and to vr potentiometer of 10K value which act as adjustable voltage dividers to control\adjust the amount of voltage going to the circuit. This circuit is connected to the solar Cell then solar Cell is the connected to the lithium battery in its both positive and negative terminals. The second circuit controls the output voltage from the first circuit to the desired device and has the USB output port (adapter) that carries the voltage to the destination devices. It gives 5V voltage and 3.5 ampere. Finally the third circuit that controls the wireless charging method, where it consists from two parts transmitter and receiver, both made from copper coils rolled 20 times to give 33 UH(micro Henry). Two coils are connected one as TX and one as Rx as the next Figure shows, the receiver connected to white LED to show its ON status , then its connected to 1K, 10K, 10 ohm resistors and 3.3nF/16 V.

The testing process has been carried through the implementation of the project and has been done in several levels; first step was testing the hardware components individually before connecting them to the bread bored to make sure there working effectively. Then, testing of the subsystems which is further divided into three circuits individually, and then testing the device overall working capability after implementation and show its final output. The testing process helps to recognize the damaged components before implementation process, hence replace them in case of damage or malware.

Figure 5.8 Device Subsystems

Table 5.1 Testing Requirements Table

This section explains the three circuits after connecting them and test them each one individually in the bread bored.

Figure 5.9 Subsystems Testing

The Figure 5.8 above shows the detailed sub systems in this device which is of three types as noted; Measurement of voltage that shows charging percentage value, Wired Charging circuit and USB output port voltage controller, Wireless charging circuit. First circuit represents the circuit that measures the percentage of the device charging, where the IC KA2284 voltage level indicator is connected in series with the LEDS pins red, yellow, green, and white to show the voltage status, and 2 resistors of 10K, and 100 ohms to protect the circuit from the damage, and then connected to 220UF capacitors. This is then connected to resistance regulator, and to vr potentiometer of 10K value which act as adjustable voltage dividers. The second circuit controls the output voltage from the first circuit to the desired device and has the USB output port (adapter) that carries the voltage to the destination devices. It gives 5V voltage and 3.5 ampere. Finally, the third circuit controls the wireless charging method, where it consists from two parts transmitter and receiver. These sub systems are connected as required to do the needed function as specified, and each sub system is connected as the Figure above shows.

Figure 5.10 Device Testing

The Figure above shows the final testing of the device, where the three circuits were combined and work together to give the desired output. The solar cells worked effectively to charge the lithium batteries and store energy in it and it took 8 hours to charge in the time between 8-4 PM. The absorbed energy stored in the lithium batteries and then sent to the voltage regulator and LED shows the percentage of the charging successfully. It varies from red, yellow to green showing the charging percentage. Then the USB output port was connected to the device that must be charged through a USB cable, and the switch connected to the USB port to control the state of device from ON and OFF. Finally the wireless charging circuit will be used if the desired charging method is wireless to use, wireless charging use EM fields to securely convey power from a transmitting to a receiving destination for the aim of charging a battery. The main voltage is converted into AC and send to the TX by the transmitting circuit, this AC has a magnetic fields that approaches the receiver coil with distance of 40-44 mm = 1.1811- 1.5748 inches. Then energy is transmitted between the transmitter and receiver the converted into DC by the receiver at the same frequency and current will start flowing to the device has to be charged. The transmitter will be coupled to the power bank circuit itself, and the receiver will be coupled to the device, for instance a phone, the phone will be charged wirelessly if it supports the wireless charging method. This was tested and the distance has been verified practically between TX and Rx.

Figure 5.11 Final Circuit after Implementation in PCB

Chapter 5 System Design and Implementation

This chapter has explained the software system of the device and its expected output, the hardware implementation of the system and subsystem circuits with its explanations, and the testing process with its result. The software implementation was done using Proteus software, and Hardware implementation included connected the components in the mentioned stages. Finally the testing was done into three stages; testing of components, testing of subsystem circuits, and testing of the device in its final stage after finishing its implementation.

Overview

This chapter includes the result obtained from testing the device in different conditions and in many stages, and a comparison between both hardware and software implementation. Additionally, a comparison between the experimental result from this device and the output from other previous literatures that has the closest idea of this device which has the name of “design and the development of a solar Portable Power Charger for A Green Energy Initiative” by Singh, Bhardwaj, & Singh (2014).

The software implementation shows only the circuit drawing, and expectations of LED in the hardware testing as explained in the previous chapter, the circuits has shown the connections of components used in this device and what it gives as expected output, where by the level of charging will be defined by the LED color as explained in the past chapters.

Figure 6.1 Software Expected Result When Charging Level Is Low (Red LED)

Figure 6.1 shows the state in which the voltage level of the storage battery is very low; hence the red LED will toggle, and it is controlled by voltage regulator so it can be increased\ decreased as needed.

Figure 6.2 Software Expected Result When Voltage Level Is High (Green LED)

Figure 6.2 shows the state in which the voltage level of the storage battery is high and battery of the device must be charged is full, hence the green LED will toggle after, and it is controlled by voltage regulator so it can be increased\ decreased as needed.

The expected output of the software simulation result has been analyzed and was proofed to function correctly when compare it to the software as expected.

After testing the hardware of the device, it has been proved that the device works effectively and has been tested properly, the following pictures explains the hardware testing output. The three subsystems was working as planned where the circuit that measures the voltage (charging) level of the battery is working and LEDs was toggling one by one successfully controlled by the voltage regulator. Then the wireless charging circuits consists from the transmitter and receiver both worked affectively and the LED in the receiver was blinking. Finally the circuit of USB port showed the expected result where it charged a USB charged phone within the time expected.The device showed it can achieve high efficiency at the time between (11AM-4PM) where the sun is perpendicular to the earth, and the solar cells can absorb more energy at that time. While it has proofed that it takes 10-11 hours for the solar Cell to charge to its maximum ability and then to charge a Smartphone.

Figure 6.3 Hardware Result out Put

The hardware result has matched the software expected output. The output of the software result has been analyzed and explained in chapter 5, as well as the output of hardware which has been shown. Result carried out from both software expectations and hardware testing was proofed to function correctly as expected. And the device working was explained in the methodology section.

From the previous literatures that have been analyzed to support this project, development of a solar Portable Power Charger for A Green Energy Initiative by Singh, Bhardwaj, & Singh (2014) was the most related literature to the device in this project. Where by almost the same methodology has been used in this device that depends on capture, store, and then charge. The difference is in the hardware implementation where the authors of literature used PV solar cells, wind module adapters, USB module, LCD display, PIC8f452 microcontroller(op-amp),DC-DC boost converter, li-ion battery( 2000mAh,3.7V). (Singh, Bhardwaj, Singh, 2014).the result derived from the implementation was that the device affectively works faster during mid-time of the day (12-4) pm, and that it stores the energy faster at that time (Singh, Bhardwaj, Singh, 2014).

While in this solar wireless charger PV solar cells was used and there wasn’t any type of microcontrollers used. Also, wireless charging circuit is not included in the previous system, while it’s added in this device and proved it worked affectively. Finally, the result obtained after testing the device showed that it needs 10-11 hour to charge the and to charge a smartphone.

Figure 6.4 Solar Power Bank with Wireless Charge Model.

Chapter 6 Results And Discussions

This chapter included the result obtained from testing the device in different conditions and in many stages, and a comparison between both hardware and software implementation. Additionally, brief comparison between the experimental result from this device and the output from other previous literature device was mentioned.

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To conclude with, this project aimed to be useful for all kind of people anywhere and time, helping them to recharge their phones and devices with no need for wires constantly and using a clean energy source which is solar energy. It helps keep the environment clean and safe, as well as supporting the idea of designing a practical and small size power supply using solar cells. During the current semester, the project implementation was done successfully and the results and testing analysis has been stated in the previous chapters. This device can be used at any spot that has good sunlight and can be used to charge for different times. It aims basically to charge phones, MP3 players, pads, and other small devices charged by USB ports.

The idea of the system is summarized as following; solar cells capture the energy and give out capacity of 5V from the sun and store it in the lithium battery, then it is converted into electrical power and send to the USB port if the wired charging method is used, and the wireless charging circuit if its required to use it for charging.

The project has been done after several research phases about the topic from different sources like websites, e-books, journals, and previous literatures that has been reviewed in the second chapter. And from these sources, a clear idea about how to implement the project has been extracted like choosing the software program to draw the circuit of the device in, and recognizing the right hardware components to implement in such devices. Finally, implementing the device and getting the results and analyze them.

The design phase has started with making the device block diagram and flow chart that gives the reader good background about the device, then comes the software design in the Proteus software and has been modified several times, after that was the hardware implementation and testing phase which is final phase.

Software implementation has shown the connection of the devices as needed and shows the expected output in the hardware circuit, since there is no simulation output from this device.

Hardware implementation has matched the software expectations, where the circuit showed the expected output by the color of the toggling LED, and the toggling LED in the wireless receiver part.

Testing of the device has been done in different conditions and in many stages and a comparison between both hardware and software implementation was done. Additionally, a comparison between the experimental result from this device and the output from other previous literatures that has the closest idea of this device was done, the literature which has the name of “design and the development of a solar Portable Power Charger for A Green Energy Initiative” by Singh, Bhardwaj, & Singh (2014) was the closest one to this device.

The report included several chapters explaining about the working criteria of this device, beginning of the report included explanation of project aim and objectives, working method, feasibility, and main points related to this project, Followed by the previous literatures about the solar energy and its usage in general, then the pre-design and the methodology used in this project, and explanations of the steps have been follow to successfully complete this project. Moving on to the device design explanation and its block diagram, as well as hardware components included in the device, and implementation phases of the given device which are software and hardware implementation phases. Software implementation includes drawing the circuit in the Proteus software and dividing the circuit into three main sub circuits. Moving on to the hardware section which will include the implementation of the components of the device and the how it is connected in. After testing, results obtained from the device in different conditions and in many stages was shown, and a comparison between both hardware and software implementation was stated. Additionally, comparison between result from the device and the result from other previous literatures devices that shares the same idea like “design and the development of a solar Portable Power Charger for A Green Energy Initiative” by Singh, Bhardwaj, & Singh (2014). Finally, the conclusion was made that sums up the report structure and what each chapter contains briefly, as well as recommendation of how to improve the device will be stated and a peek on its future usages.

Chapter 7 Conclusions

This device will be used to replace a lot of similar working devices and has a lot of positive influence not only on the devices, for the environment in the first place.

According to the results obtained from the testing of the device, the following recommendations has been identified to improve working of the device and summed up into

· Using solar Cell that gives 8V output to improve the quality of absorption in the current cells.

· Maximize the lifetime of the device by using plastic anti thermal cover to the circuit of the device to protect it from high temperature while charging the solar cells.

· The device can be enhanced by using a microcontroller to improve its working ability such as MSP 430 microcontroller and an Arduino type MCU which can modify the whole applications of the device and improve features like extend the distance of the wireless charging method.

Chapter 8 Recommendations/ Future Work

As the world is developing so fast, people started to be aware of the importance of having clean energy sources and help keep the environment healthy for now and next generations. Clean energy field in expected to be a very active field in the next few years, which make this project one of the options to be used for charging instead of the environmentally harming one, and gives interested people from this side of the world to get the maximum benefit from the sun! This device can be enhanced by adding larger numbers of photovoltaic solar cells to give higher energy to the battery hence to the whole device. Also, this device has future applications to be used in schools and universities to apply more researches and modified results. Moreover, and for the maximum benefit from the solar energy, the use of solar charges should be compulsory in elementary schools and high schools so that the next generation will have enough awareness about the importance of clean energy sources.

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Project selection

litrrature analysis

Requirments

Implemintation and testing

Design phase

Costing

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