Solar Battery Charger - Mapúa Institute of Technology
Contents
1. l Regulator Switch amp to use Z i the voltage regulator gt to i bypass the regulator OOFF I Voltage Regulatoruseto poo adjust the voltage being Supply to the device I i p sssssusansssamamanaso A i Source Switch 010 use 774 solar panel as source to use i i internal battery as source i PES IT ndicator i I internal battery is i ri charging rig Green there is voltaqe i PARDEE Ji poem n L Y 21 rae Built In VOM Display use i omouamumonoumamonanaumaumnanaumamononoumumonoumanonouaamumoncumnamnonanoumumonoumamomn to display the voltaqe beinq i read by the PIC 61 Solar Panel Charging Using the Solar Panel 1 Connect the solar panel to the jack Expose it to the sunlight 2 Switch the source switch 3 Switch the regulator switch according to your choice the green indicator must turn on this indicates that there is voltage being supplied to the system 4 Connect the cellphone battery charger or any charger that is suitable to the cigarette phone jack 5 If you choose to regulate the voltage adjust the voltage regul2. fimectcounter with be during SLEEP wis exis crystaliciocs Timez 31 timencourier with 8 bE pera register prescaer and postscaler Two capture Compas modules Capture 15 reson Is 12 5 Compare 15 1E H resolution is 200 ns FAM max resolution 15 10 12 0 mulll chancel Analogo comverier Eynchrenacs Sera Part 952 wih Se Masher modas and ashen Sieve Universal Synchronous Asynchronous Transmitter SAAT ST wih Sof address Slave Fort FEE 8312 akie wih RD WR and CS controls 404 any detectian for Reset OR 51 PIC16F87X Pin Diagrams PDIP S000 Ee L e og os wow O K KG ROLL REO E ee RECIEN 012 PICIEFBTA OSCIHCLERB _ 14 i aa 16 1 SE Bas 2 nrppspz ZXSIDL e soit ma APS PO aes a a oe 7 ase Oo fees an mr SOO oe 39 mp APS OO AZ CH2CH epi a REAKTE RETREAT EAR Zi ED Rap aT
3. 10 PO 11 10 n access Ba nk to 7FH 96 bytes to 6FH 80 bytes to 6FH 96 bytes to 6FH 96 bytes STATUS reg RP1 RPO x x to Bank 3 70H to KIRK OK EE OE E RRR RRR RRR RIK KR RBA BOR BRK RR RK RRR RRR RR ARIK ADCO_HI ADCO LO Hundred Ten Unit Disp Ctr Temp1 Temp2 equ equ equ equ equ equ equ equ Variable Declaration 0 1 11 2t 13 14 78 79 temporary variable 43 Temp3 equ Temp 4 equ H 7A H 7B Se RA RA KK OR SK UK UR RRR IARI BARR RIK RSE HR ASA j Reset Vector Starts at Address 0x0000 org goto org routine goto 0x0000 Initialize 0x0004 ISR routine 7 7 7 start of reset vector start of interrupt service BIRR RRR IR BAKER RRR bsa UK ICR BORER BD KER Initialization Routine CRRA EAR ARERR BARRED RAR RR UK KR QR RA RK RRR KCN RRR KBAR NUR OR ROW RRA BER KORA org Initialize clrf bcf bsf movilw movwf movlw movwf movilw movwf movlw 0x0008 TMRO INTCON STATUS RP1 STATUS RPO B 11000011 OPTION REG B 00001110 ADCON1 BELL TRISA B 00000000 7 7 7 7 7 Clear TMRO Disable Inte
4. substantial possible solution to the problem was outlined This was followed by gathering information about the materials and components to be used and checked again as to its usefulness and suitability as far as the design was concerned When all the needed materials and components were gathered the development and creation of the design started 17 Identifying of the problem Creating a draft of p Gathering information for the materials and components appropriate for the research design Developing the research design End Figure 2 Design Procedure 18 Design Procedure for Actual Design The design was started by researching on and finding the materials components suitable for the creation of the prototype The appropriate products to be used were identified through data sheets researched on other related documents The detailed steps in constructing the research design are as follows Develop the PCB layout of the solar battery charger using the PCB Wizard software Print the PCB layout in acetate Cut the printed circuit board in 3 x3 5 Place the printed acetate with PCB layout at the top of printed circuit board Expose it to UV light for about 30 seconds up to 1 minute Dissolve right amount of developer in water and place the exposed printed circuit board etch the circuit layout When the circuit layout is clear and visible wash the printed circuit board with water to avoid cont
5. ADRESH W movwf ADCO HI movlw B 00000001 gt Test if ADC conversion Done get A D result 48 Start_ADC Read_ADCX movwf bsf return ADCONO ADCONO 2 7 7 ensure A D is active start A D conversion BRIER IER ISR RR BEAD BE FOR UR BIN2BCD Inc 100 Inc 010 Inc 001 cl rf clrf LET movlw subwf btfss goto movwf incf goto movlw subwf btfss goto movwf incf goto movf movwf Hundred Ten Unit D 100 Temp2 W STATUS C Inc_010 Temp2 Hundred Inc_100 D 10 Temp2 W STATUS C Inc 001 Temp2 Ten Inc_010 Temp2 W Unit 49 return PARRA REAR KIER KAREN RAR REMI IR RSE UR GEEK OE EK UR CA ERASER BRK AKER aspa RSA BEER hka Delay movlw D 250 movwf Templ H Dly Loop decf Templ F movf Templ W btfss STATUS Z gt goto Dly Loop return FERRER ACEI KBAR BERRI BRR ORDRE RB RSE UR UK GIC UR BR RRR GR COR GR UNT BEE KER AER UR end QUK KR AAR RUE ORDRE EGER kiku E IIR ASE BR 50 APPENDIX C MICROCHIP PIC16F8 X 28 40 Pin Bit CMOS FLASH Microcontrollers Devices Included thie Data Shaet FIGISFET PICIEFETE aa PID15F877 Microcontroliar Core Faatures High perfoma
6. FAST DICK ROP b Coir rr PME MIO DTI G RANAR RADAROM eb ter ELS PIC16F87X Kay Fax Urez 2 Cmlora Mid Range Rafersnos FIC38FBT3 FK 18FH74 FICTEFETA FICTBFE7T 1 2223 20 MHz RE SETS Deinysi i FOR BR 1 I M 1 GET Fi FLASH Program Memory A 32 38 8 z eS ee k ee ee 5 Pom je DUE e s S 3 T J Parse communicado mee E eec cep PEF 35 inaction auctona metuctons 53 APPENDIX D vationat Semiconductor LM78XX Series Voltage Regulators General Description Thao LM EX X sonhos of Too Sorrminal regulators soroa iad output woltsges making Tem useful in a wide rango of appicason Oma of these balon card oliminaing te distibuton probos singa ragulaton Tho wohages malabo alow fuso raguiatons to ba used in bgo saima ins urmonia fon HiFi and offer solid state abectronic AL ough dasignad primarily zs vonage mgulatars thoso cdevicos weed wit odana componant to obian adju woltagos and coumans Tho LMT 8X X sores in an alumnum TC 3 pack ago wh
7. infrared radiation escaping from the collector specially coated glass covers can be used This coating should be on the inside of the covers Dixon and Leslie 1979 CdS Thin Film Solar Cell The CdS thin film solar cell is photovoltaic device made from a thin polycrystalline film of semiconducting CdS which is deposited on a suitable substrate The essential features are a substrate a CdS layer a barrier layer and contacts The substrate may be conducting or insulating thin and flexible or thick and inflexible transparent or opaque The CdS layer is usually formed by vacuum deposition and is generally but not necessarily between about 10 and 30 mhu in thickness with an average grain diameter on the same order The grains are normally disposed with the optical axis approximately perpendicular to the substrate with fibre axis orientation The CdS film is invariably n type semiconducting with resistivity usually within about one order of 10 ohm cm and hall mobility in the plane of the film within about one order of 10 cm V sec Shirland 1966 Film Cell Construction 1 Backwall cells Backwall CdS film cells can be made using either opaque or transparent substrates With an opaque substrate the rectifying electrode or the barrier layer must be deposited first and the CdS film is deposited as an over layer A ceramic substrate is coated with a layer of 5 and the CdS film evaporated onto it and contracted with a collector elect
8. solar panel The solar panel could provide up to 17 3 V depending on the intensity of sunlight 21 The voltage regulator would controlled the voltage entering the device The voltage rate would be read by the microcontroller and would act as the voltmeter that would display the voltage reading through seven segment displays Voltage Regulator Figure 3 Block Diagram of the Hardware Design 22 List of Materials Description Quantity Price per Total Unit PIC16F877 Php 530 00 Php 530 00 10K Array Resistor Php 12 00 Php 24 00 4MHZ External Resonator Php 35 00 Php 35 00 W10G Rectifier Diode Php 10 00 Php 10 00 2 Pins Terminal Block Php 15 00 Php 15 00 7805 Voltage Regulator Php 15 00 Php 15 00 Heatsink Php 20 00 Php 20 00 16V Capacitor Php 3 00 Php 3 00 2907 Transistor Php 3 00 Php 18 00 12001 16V Capacitor Php 6 00 Php 6 00 Assorted 1 4 W Resistor Php 0 25 Php 3 75 Toggle Switch Php 18 00 Php 36 00 Potentiometer Php 38 00 Php 38 00 3 Digits 7 Segment LED Php 65 00 Php 65 00 Battery Holder 3x3 Php 45 00 Php 45 00 Battery Holder 2x2 Php 30 00 Php 30 00 Plastic Case Php 125 00 Php 125 00 olar Pane Php 4 000 00 Php 4 000 00 Cigarette Phone Jack Php 80 00 80 00 Cigarette to Battery Alligator Php 50 00 Php 50 00 Cigarette to Battery Nokia Charger Php 100 00 Php 100 00 Cigarette to Battery USB Php 100 00 Php 100 00 Connecting Wires Php 25 00 Php 25 00 Printed Circuit Board Php 50 00 Php 50 00 un
9. that the researcher created solar energy could now partially resolve the problem in electricity usage Objective The objective of this project design was to create a prototype of a solar battery charger preferably for AA rechargeable batteries and some mobile devices A USB port adaptor was included in order to charge mobile devices such 11 as Nokia cellphones MP3 players and other devices utilizing the same voltage range and ports Due to the uncertainty of receiving full charging capacity from the sun an internal battery would be charged to supply additional emergency voltage Using a PIC microcontroller the team would designed a voltmeter The voltmeter would be used to indicate the voltage output of the charger to the user Together with a voltage regulator this would prevent supplying the load with incorrect voltage Utilizing solar panels with a charger would make the voltmeter very versatile and mobile device It can be charged almost anywhere for as long as it is exposed to direct sunlight over a period of time If under less optimal weather condition internal batteries will still ensure that the charging continues The research team worked on this study for the benefit of mobile appliance owners The study was meant to supply the owners with information that could benefit them The study would provide them with an almost unlimited source of energy for their electronic devices even during less sunny days or under b
10. the device If the user prefers to use the energy from the solar panel the converted solar energy will be transferred directly to the device During charging either the user prefer to use the internal battery or the solar panel as the source the microcontroller will respond and will be used as the voltmeter that will read the voltage being supplied to the device The potentiometer will serve as the voltage selector Using the switch the user can select the voltage supply either fixed or varied 10 As the output the seven segment will display the voltage read by the voltmeter The processed energy will charge the device If the user prefers to charge the internal battery alone a LED will activate this indicates that the internal battery is being charged In case the user prefers to use the internal battery or the solar panel as the source yet there is no enough energy definitely the device will not charge Statement of the Problem As of today the most prominent problem that the country faces is the price increase of basic necessities such as petroleum water food and electricity With the price increase people resort to alternatives to make the cost of living cheaper Given this premise the research team desired to help people cheapen their cost of living by reintroducing solar energy as an alternative to electrical energy in some cases Solar energy is a great alternative for power because it is renewable and free With the device
11. the user still has the option whether he wants to use fixed value of voltage from the solar panel or vary it according to his requirements Basically the solar battery charger can function without the microcontroller The microcontroller functions as the voltmeter for the system It detects the voltage that is being supplied to the device The electric energy as the input is converted in binary code that is done inside the microcontroller and the program will manage how the data will be arranged to have the expected result or display 26 Hardware Implementation Upon completing the research study the team designed the prototype carefully chose devices needed to implement the prototype After completing the prototype the members troubleshot and tested the design They used different cell phone units to charge using the solar battery charger MP3 MP4 and iPod were also used to test the charger All units were successfully charged Software Design The program for the microcontroller was meant just for the built in voltmeter that could be found in the prototype The program was created using assembly language programming a low level language that implements numeric machine code and other constants needed to program computer architecture Actually the PIC microcontroller could be program using other languages but it is only assembly language that has the free downloadable compiler available in the internet The compiler which is the MPASM i
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13. 1111 PORTD 7 PORTD 6 PORTD 5 B 00000001 ADCON0 ADC0_HI ADCO LO Disp Ct BIN2BCD 01 11 01 00 11 00 r E 7 r 00 001 select ANO to convert QUIERO BRA BR BRIER RKB RR RK BIR BR BERK RR ICR SEE RUE BIRR aksa Display bsf PORTD 7 46 Disp_100 Disp 100X Disp 010 Disp 010X Disp 001 bsf bsf movf sublw btfss goto movf andlw call movwf bcf nop movf sublw btfss goto movf andlw call movwf bcf bcf nop movf sublw PORTD 6 PORTD 5 Disp Ctr W D 2 STATUS Z Disp 100 Hundred W H OF Seg Table PORTB PORTD 7 Disp Ctr W Dri STATUS Z 010 Ten W H OF Seg Table PORTB PORTB 2 PORTD 6 Disp Ctr W D O 47 Disp 001 DisplayX btfss STATUS Z H goto Disp 001X movf Unit W gt andlw H OF call Seg_Table 2 movwf PORTB bcf PORTD 5 incf Disp Ctr F movlw D 3 subwf Disp Ctr W btfss STATUS C gt goto DisplayX clrf Disp ctr H call Read ADC movf ADCO HI W movwf Temp2 gt call BIN2BCD return H eR OK RR A BAKER RRR UK DK RUE BRAK ish ORO EUR Read_ADC btfsc ADCONO 2 gt goto Read_ADCX movf
14. 5 maj Total Php 5 423 75 Table 2 List of Materials 23 Hardware Component The solar battery charger alone is basically composed of solar panel diode internal battery capacitor switch voltage regulator potentiometer and cigarette phone jack The solar panel collects solar energy and converts it to electric energy A diode is placed after the solar panel to avoid feedback effect of the electric charge Feedback effect may happen once the charge of internal battery is greater than the energy that the solar panel is providing The internal battery is placed to serve as storage and source of energy Capacitors are used to check if the energy flowing to the system is DC or AC Switches are used to switch ON or switch OFF the prototype and are also used to select the function of the charger select panel or internal battery as a source and select if the voltage produced can be varied or fixed Once the user prefer to use the charger with a specific voltage rate that is the time the voltage regulator is used thru the help of the potentiometer Finally the cigarette phone jack is used as the outlet for charger that the user prefers to use Aside from the charger the prototype also has built in voltmeter The voltmeter is basically composed of array resistors crystal capacitor microcontroller and the 7 segemnt display The array resistors convert the ac to dc The crystal defines the operating frequency of the mic
15. Dixon and Leslie 1979 Characteristics of the Components of Flat Plate Collectors A flat plate collector normally consists of an absorber which is made of blackened metal usually copper and a grid of pipes soldered to the absorber The assembly is placed in a box with insulation at the back of the absorber and one or two transparent covers at the top to allow sunlight in Approximate Thermal Material Density Conductivity kg m Wm Mineral wool clay fiberglass rock 12 14 0 0332 0 0404 Hair Felt 8 0 0389 Granulated Cork 120 0 0476 Re granulated cork 0 474 cm particles 30 0 04471 Compressed cork 136 176 0 0418 0 0462 Straw 10 13 0 0576 Sawdust 13 240 0 0649 Vermiculite granulated 128 0 0721 Polyurethane foam rigid 24 0 0245 Polystyrene expanded Table 1 Properties of Commonly Used Insulation Materials The properties of commonly used insulation materials are shown in Table 1 Plastic materials such as PVF and fiberglass sheets have been used in solar heaters but they are in general inferior to glass because they deteriorate with time and at high temperatures Moreover ultraviolet radiation discolors them The plastic cover is however easier to handle than the glass cover The theoretical analysis for a flat plate collector is well established and can be summarized in the equation Qo Qa QL where Qo is the power output Qa is the power absorbed by the collector and QL is the power l
16. Solar Battery Charger By Christian Peter C Antonio Jian B Madrona A Design Report Submitted to the School of Electrical Engineering Electronics and Communication Engineering and Computer Engineering in Partial Fulfillment of the Requirements for the Degree Bachelor of Science in Computer Engineering Mapua Institute of Technology September 2008 Chapter 1 DESIGN BACKGROUND AND INTRODUCTION Introduction One of the least tapped sources of energy is the solar energy Solar energy is free and does not create harmful by products The Philippines is one of best places to harness this form of energy because it is located near the equator Being a tropical country exploiting the powers of the sun is very advantageous for the people The team would like to use this form of energy by transforming it into electricity that would be used by a particular device As of April 24 2008 Meralco as the largest electricity provider in the Philippines announced that it was raising its rates This was another factor why the team conducted this research design Aside from saving on their electric consumption to keep their electric bill low people can save further by using solar energy to charge their devices This alternate energy source is even free of charge Solar cell is a key device that converts the light energy into electrical energy in photovoltaic energy conversion This was the reason why the research team chose solar cell to be the
17. The solar battery charger was able to charge the internal battery that served as alternative source especially at times that there was no available solar energy It was learned that the designed device could provide up to 25 5 V if charged directly from the solar panel and 13 5 V if charged directly from the internal battery Through testing it was noted that the voltage value being displayed by the built in voltmeter was higher than the actual voltage that was supplied to the device being charged Specifically there was atmost 9V difference between the actual voltage being supplied and the value being displayed by the built in voltmeter This 9V was the result of 5V being used by the microcontroller and 4V being used by 2 LEDs Recommendation Several improvements can be applied to the device to further enhance its capabilities like calibrating the voltage entering the microcontroller to display the exact value that is being supplied to the device Other improvements can be applied to the design for it to produce higher voltage rate so that it can also be 39 used as alternative energy source for laptops computers refrigerators and other electronic or electric devices that are commonly used 40 BIBLIOGRAPHY Alexander Charles K and Sadiku Matthew N O 2003 Fundamentals of Electric Circuits 2 Edition McGraw Hill New York Dixon A E and Leslie J D 1979 The Technology of Flat Plate Collectors Solar Energy Conversion Perg
18. ad weather condition Significance of the Design This design would help people especially Nokia cell phone users and the users of other devices utilizing the same voltage range and ports to save money at the same time utilize energy that is nature friendly As students this 12 project design is very important because through this study the team members were able to apply and practice their technical skills and accumulated knowledge and learning s This prototype was also created to minimize the expenses of the people especially during these times when the price of electricity keeps on soaring Scope and Delimitation The study was concerned with the development of a design called Solar Battery Charger that would serve as alternative to or replacement for the electric battery charger available in the market The research study set the scope and delimitation as follows The scope 1 The prototype is able to charge batteries that require 1V 17V recharge 2 Devices such as cell phone MP3 and PDAs are the devices that solar battery charger can charge 3 A voltmeter is also attached to the said device to monitor the voltage that is being supplied to the system 4 Internal battery is included to allow the unit to store energy that is very useful at times when there is less or no solar energy due to charging weather condition 5 LED indicators are included as to show if there is voltage running in the system and if the internal battery is ch
19. amon Press New York Floyd Thomas L 2002 Electronic Devices 6 Edition Pearson Education Inc publishing as Prentice Hall New Jersey Oxford 2007 Soanes Oxford English Mini Dictionary 77 Edition Oxford University Press Inc New York Podbielski John 1999 Collins English Mini Dictionary Second Edition HarperCollins Publishers Great Britain Shirland Fred A 1966 Electronic Research Division Clevite Corporation Cleveland Ohio U S A Soga Tetsuo 2006 Fundamentals of Solar Cell Nanostructured Materials for Solar Energy Conversion Elsevier 41 APPENDIX A Circuit Schematic Diagram ssssss 55 LI F87 Tl gt 2 uum L vL h gt 19K js THz Figure 8 PCB Layout of Solar Battery Charger APPENDIX B Source Code P RSEN OR OE UN UK EUR Sap Saku ue vcro ANNE e ip ux oet gun e UR S a oe RR oc eo on config ALL File SOLARBAT ASM 4Mhz ceramic resonator processor include 5 OSC amp WDT OFF amp PWRTE 16 877 P16F877 inc ON amp OFF amp BOD EN OFF amp XXXX General Purpose RAM location Bank Bank Bank Bank Note commo PO 00 20 PO 01 20 PO 10
20. an provide at a given time Based on the table from six in the morning where the sun starts to provide solar energy the ampere being supplied by the solar battery charger started to increase From 290mA at six in the morning it increased to 380mA at one in the afternoon 380mA is the maximum ampere that the solar battery charger can provide After one in the afternoon the ampere being supplied by the charger started to decrease 35 Time Amperes produced by the Solar Battery Charger 6 00 AM 290 7 00 300 8 00 310 9 00 320 mA 10 00 AM 340 mA 11 00 AM 350 mA 12 00 PM 360 mA 1 00 PM 380 mA 2 00 PM 370 3 00 f 350 mA 4 00 PM 340 mA 5 00 PM 310 6 00 300 mA Table 7 Amperes Produced by the Solar Battery Charger in a Given Time With the given information from Table 7 it was learned that the minimum ampere that the charger could provide was 290mA and the maximum was 380mA The data were utilized to come up with Table 8 and Table 9 As presented in Table 7 at six o clock in the morning the solar battery charger could provide 290mA which is the minimum supply in the morning whereas at one in the afternoon the solar charger could provide up to 380mA supply which was the maximum supply It can be concluded therefore that one o clock is the best time to use the solar battery charger However the users are encouraged to utilize the solar battery charger anytime Tabl
21. arging The delimitation 13 1 It can only charge devices like cell phone MP3 player MP4 player and others devices that require voltage range from 1V 17V to charge 2 It only charge internal battery if the solar panel provides 12V or higher 3 Chargers that are suitable for cigarette phone jack are the only ports that the solar battery charger can provide 4 Solar battery charger cannot be used during night time unless the internal battery is fully charged to support the voltage needed by the device to recharge Definition of Terms Adaptor is a device connecting electrical appliances to a single socket Oxford 2007 Battery a device containing an electrical cell or cells used as a source of power Oxford 2007 Capacitor is a passive element designed to store energy in its electric field the most common electrical components It is consisted of two conducting plates separated by an insulator or dielectric It is an open circuit to dc used extensively in electronics communications computer and power systems Alexander and Sadiku 2003 Cellphone is a mobile phone Oxford 2007 Charge is meant to store electrical energy in a battery electricity existing naturally in a substance Oxford 2007 Charger is a device for charging a battery Oxford 2007 14 Heatsink is an environment or object that absorbs and dissipates heat from another object using thermal contact either direct or radiant Heat sinks are u
22. as xx8 WT1 54 Physical Dimensions incha 380 845 5808 0350 E350 Hd 107 8 123 ENG 1 124 0023 4 ns FTT EEATING PLANE 113013 34 Amam pum n br 11 10 CGE p 161 1 385 0 178 4 547 Dm B 675 15 88 1T 15 T TIT 3 187 PAH i Aluminum Metal Can Package Order Humber LM7505CK LM7812CK o LM7815CK NS Package Number 2 LM78XX Series Voltage Regulators Physical Dimensions mitimatorsi Conte eg Qs 4 153 z 280 isi hh 450 ius E 122 404 me 13057 1322 jairen 4 454 210 1 1 s ihe ad 44 0 0 pas amn EM ua w i a B Y FLAME TO 220 Package T OrdarWHumbar LM7812CT or 815CT INS Package Number TOSE LIFE SUPPORT POLICY NATIONALS PRODUCTE MOT AUTHORED FOR US AZ CAMCAL COMPONENTS IN UFE SUPPORT DEVICES OF SYSTEMS WITHOUT THE EXPRESS WATTEN APPROVAL OF THE OF NATIONAL ZEMPBOGONDUCTOR CORPORATION usod honar 1 Lio support davies or am diom or 2 systems which
23. ator according to the voltage that is needed by the device Oto maximize Oto minimize 6 Connect the device to the charger Disconnect when battery is full NOTE If the device is not charging try to adjust the voltage regulator or try to expose the solar panel to a better place where it can gather more solar energy Charging Using the Internal Battery 1 Switch the source switch 2 Follow procedure no 3 6 62 NOTE Make sure that the battery has enough voltage to charge the device To check switch the switch regulator to bypass and read the voltage that the internal battery has using the built in VOM display If the internal battery has no enough charge follow the procedure below Charging the Internal Battery Using the Solar Panel to charge it using the solar panel Charging the Internal Battery Using the Solar Panel 1 Connect the solar panel to the jack Expose it to the sunlight 2 Switch the source switch This is done to make sure that the internal battery is connected to the system 3 Position the solar panel in an area where there is enough direct sunlight 4 Notice if the red light is on to indicate 5 To check the charge switch the switch regulator to bypass and read the voltage that the internal battery has using the built in VOM display NOTE If the battery is not charging red light is off it only means that the solar energy being collected by the solar panel is not enough to produce 12V Try to
24. ctions The first work along these lines was evidently done by RAVICH at Itek Laboratories His cell structured was like that shown in Figure 6A Th CdS film was formed onto 5 coated glass substrates and the barrier layer was contacted with an evaporated gold electrode Ravich also tried a comb like metallic grid photoformed in place on the substrate instead of the SnO layer This was however not very satisfactory because it could be made with only about 50 of the substrate surface uncovered The gold film evaporated onto the barrier is compatible with the barrier electrically but unfortunately it is not very conductive unless it is made thicker in which case it is not very transparent This cell construction is severely limited in output by series resistance Shirland 1966 Performance 1 Power Output 2 Voltage Output 7 8 Current Output Effect of Illumination Intensity Time response Effect of temperature Spectral response Stability Conclusions and Future Possibilities The CdS thin film solar cells described in this paper have not flown in space and they have not been made in production There is further development and engineering work required in order to qualify them for space and to develop the fabrication processes for mass production More than 800 cells have been made of the 50 cm area size in the laboratory having conversion efficiencies greater than 4 These cells have been sho
25. device such as cell phone and MP3 To start the prototype must be turned ON The user has the option if he wants to charge the device directly from the internal battery or the solar panel Whether the user chooses solar panel or the internal battery as the source for charging the device either of the sources must have enough energy to charge the device In charging the user still has the option if he wants to have fixed or variable voltage that will be supplied to the device 28 Voltage Regulator Charge Full Charge Figure 5 System Flowchart of Solar Battery Charger 29 Prototype Development Figure 6 Actual Photo of Solar Battery Charger Figure 6 shows the actual appearance of the solar battery charger The prototype that the group developed is an actual size prototype All components were carefully chosen to produce an efficient prototype From researching designing developing up to testing the group carefully gathered data and implemented the design accordingly Other actual photos of the prototype are presented on the Appendix E 30 Chapter 3 TESTING PRESENTATION AND INTERPRETATION OF DATA The Solar Battery Charger was tested using VOM Although the research design has a built in voltmeter this was done to assure the reliability and efficiency of the prototype Since there are four functions that the prototype can provide there were also four testing done one was having solar panel as sourc
26. e with fixed value of voltage supply two is having solar panel as source with variable value of voltage supply three is having internal battery as source with fixed value of voltage supply and four is having internal battery as source with variable value of voltage supply The following steps were done to come up with the results 1 To get the voltage that was collected by the solar panel tap the VOM was tapped directly to the solar panel connector The VOM reading was recorded 2 To get the value for Built in Voltmeter Reading switch the regulator switch was switched on to bypass to get the fixed value and the reading of the built in voltmeter was examined 3 The voltmeter was tapped to the cigarette phone jack to get the voltage being supplied by the system to the device The result was recorded on the voltmeter reading column 4 To get the voltage that was supplied by the internal battery tap the VOM was tapped directly to the internal battery connector The VOM reading was recorded 31 5 To get the value for Built in Voltmeter Reading the regulator switch was switched ON to regulate The value was made varied then step 3 to 5 was repeated for every voltage reading of the built in voltmeter Using Voltmeter Voltmeter Reading Directly to the Solar Built in Voltmeter Reading Panel 24 2 17 5V 25 5V Table 3 Solar Panel as Source with Fix Value of Voltage Supply Table 3 presents the built in voltmeter which displa
27. e 8 shows the battery charging hours of any device with 290mA supply and Table 9 shows the battery charging hours of any device with 380mA supply As observed any device that used 36 380mA as supply charged faster than with 290mA supply The group had the option to use rapid charger on Nokia battery only As expected the rapid charger unit charged faster than the ordinary charger unit Capacity Time hrs Capacity mAH 290mA Device Battery Type Ordinary Rapid Charger Charger Ni Mh AA 2400 8 Nokia BL 5C 600 _ 2h f 1h Nokia BL 4C 600 2h 1h Nokia BL 4C 720 2h30m 1 20 Noka6015i 950 3hl5m 2h Nokia BLD 3 720 2h30m 1 20 Nokia3285 550 2h 1h Nokia BLS 2N 900 _ 3h 1h 15 Nokia BLB 2 840 2h50m 1 45 Nokia BLB 3 1020 3h30m_ 2 10 Nokia BLC 2 950 3 30 _ 2h Nokia BMC 2 1020 37 3h30m 9 2h3m Nokia BMC 3 2280 _ 8h 3h 40m LG LGLP AGKM 800 _ 2h45m t LG LGLI AGKL 1200 4 10 _ HTC Touch XV6900 900 10 _ HTC BTR6900 1100 3 4 HTC BTE6900 1880 6 30 Ipod battery 60GB 700 2h30m T Ipod battery 30GB 50 _1h50m Apple Ipod 4th Gen 950 3h 30m Apple Ipod 3rd Gen 600 _ 2h Apple Ipod 1st and 274 Gen mini series 400 1h 30m Apple Ipod 1st and 2nd Gen 1600 5 30 _ s Asus MyPal PDA Battery 3 7V 1300 4h30m _ Asus PDA Battery 3 7 1200 41010 LCD MP3 player 1GB mini pocket size Lithium 5h Table 8 Batte
28. e voltage entering from the solar panel was also consumed by the other components of the system Using Voltmeter Voltmeter Reading Directly to the Internal Battery 1V 1 2V 4 7V 2V 1 2V 4 7V 3V 1 5V 4 7V Built in Voltmeter Reading 4V 2 1V 4 7V 5V 2 6V 4 7V 6V 2 9V 4 7V 7V 2 8V 4 7V 2 9 4 7V 9V 3 5V 4 7V Table 6 Internal Battery as Source with Variable Value of Voltage Supply 34 Table 3 4 5 and 6 show the results of the testing the research design with voltmeter As seen in Figure 4 which is the schematic diagram of the Solar Battery Charger the voltage that was being sensed by the microcontroller passed through the microcontroller itself and the two LED specifically the microcontroller that used 5V at most before it operated Also the LED display use 2V to activate since the system has 2 LED which is equal to 4V All in all there was 9V at most that were used by the system before it was useD by the device to charge The same reason applied to other table The difference between the built in voltmeter and voltmeter readings was not more than 9V Noticeably the value of the voltmeter reading that was directly connected to the solar panel varied from time to time It was because the solar panel could not collect constant solar energy that was converted to electric energy Those values have positive or negative 5 accuracy difference Table 7 shows the ampere that the solar battery charger c
29. expose the solar panel to better place where it can gather more solar energy 63
30. ich will allow ovar 1 0 4 load curent adeguata haga ainking provided Current limiting included to limit tia poak oripa curent to a sa a ama dor m provided to mit pow dask Paton B internal power bacomas too high for hast sinking provded tro oma shutdown ciwit ower preventing IC from ovworhaaing Considamhla otor was exp andad to mala tho LM so mas of nagulaors uso Tun schematic and Connection Diagrams of componen fis not nocomary to bpem ha ouo athough doas improvo randan responsa ling brin animi nosdad ani if iho maguilmtor located iar irm iior mpanio of praa map p For output voltage othor fun Sv 12V and 15 0 1 117 sanos provides an wollage mange trom 1 2 ta 5 TV Features m Cumu cures excom of m intemal homa oralari protection m components megunod m Cumput amiko sa a amaprmicton m short curari limit m Avala a alumnum 4 packaga Voltage Range LMTSO 5C 178125 129 LMTe1 So 15v WUT 2 Bottom View Order Number LM TS05C K LMTBT2CK LMT815CK Saa NS Package Number KOIA Fasio Package Order Humber LATS or SCT NS Package Number TOSB s1ojejnBag san
31. inuous etching Place the etched printed circuit board to ferric chloride to dissolve unwanted copper in the board by shaking the container When all unwanted copper is removed wash the board with water and dry Test all the connections of copper layout using the VOM When all connections are tested and found correct drill the board according to the placement of the components Mount all the components to the board except for the microcontroller 19 10 11 12 13 14 15 16 17 Solder all components to the board Make sure that the lead is big enough to hold and connect the component to the board but not too big to avoid unwanted connection Test the function of the prototype Create a program for the specific function of the microcontroller which is voltmeter Using assembly language encode the program and with MPASM convert the program to machine code Burn the code to the microcontroller Place the microcontroller to the board Drill the plastic case and place other components that are supposed to be expose such as the potentiometer three digit seven segment display cigarette phone jack toggle switches and the LED indicator Solder all remaining connections Test and troubleshoot the prototype The solar battery charger has built in voltmeter The solar panel was designed to be detachable to make the prototype easy to carry The solar battery charger has two switches one that selects
32. is a class of electrical switches that are actuated by a mechanical lever handle or rocking mechanism Podbieksi 1999 Transistor is a semiconductive device used for amplification and switching applications Floyd 2002 Voltage Regulator keeps a constant dc output voltage when the input or load varies within limits Podbieksi 1999 Voltmeter is an instrument for measuring voltage Podbieksi 1999 16 Chapter 2 DESIGN METHODOLOGY AND PROCEDURE Design Methodology This research used structural methodology Structural methodology is a process that follows the design procedure In this case the research was started by determining the problem It was followed by reviewing related literature and studies and conceptualizing and developing the design Figure 2 on the next page shows the procedure in developing the design On the succeeding pages Figure 3 shows the block diagram of the solar battery charger and Figure 5 shows the detailed functions of the solar battery charger Design Procedure Figure 2 shows how the research study was done The first step was to identify the problem that was how to charge cell phone and other devices with the same voltage range using the solar energy After identifying the problem relevant data were gathered to support the study such as related literature and studies These literature and studies were revised Information useful to the design was recorded When the data needed in the study were already
33. main part of the prototype Mobile devices and other devices such MP3 Player and MP4 Player are everywhere but oftenly people find themselves lacking battery supply for their gadgets This usually happens when an electrical battery charger is nowhere to be found or there is no available electrical outlet where a low battery can be recharged Soga 2006 Review of Related Literature The Technology of Flat Plate Collectors Of all the applications of solar energy the use of flat plate collectors in heating is the most practical The solar liquid heater was invented by H B Saussure during the second half of the 177 century Herschel 1837 and Tellier 1885 also experimented on solar water heaters Even in earlier times the indigenous people of Africa the Arab countries Australia China India and Pakistan used their ingenuity in heating water by placing a specially shaped copper pot filled with water in the sun during the winter Air heaters however are of recent invention K W Miller introduced the overlapped glass plate air heater in 1943 Nowadays it is cheaper to use solar water heaters for domestic appliances and as such they are used all over the world From 1960 onwards flat plate collectors have had the biggest share in research and development This paper outlines the capabilities and limitations of such devices with the intention of promoting the proper use of flat plate collectors especially in developing countries
34. nce REC CFU Only 35 single word Instnectons in leam AJ single cycle Iniructiors for engram branches which are two crcl Operating speed DC 20 HHE clock input Dc 200 rs Instruction Upto E r 14 words of FLASH Program Upto 3 8 x of Bats Memory AAM Upto ZEE x 8 bytes af EEPROM Dats Pinout compatible to the FICTBCT38 748 78 77 up o 14 sources Eight evel deep hardware stack Drect and reise addressing modes Povero Aest FIC Pgwer up Timer FART and Start up Timer COST Webohdog Timer OT wih Ies mam on chip RC for reliable aperat on Programmable protection Power saving SLEEP mode options Low power high spesi CMOS FLASHIEEPROM technology Fully design Serisi Pomana SF va bano lt gt In Circult Seria Programming capability mult Debugging two pins Processor madre access fo program memory ide operating village range 2097 fo w High Shk Soure Curent 25 mA w Commercial Indusinal ard Exeendsd tempersture ranges Lowe power cansumz nri DS mA typical gb 3v 4 MHz 20 WA typical 25 32 kHz xp typical sadby curent Pin Diagram a Paripheral Faatures Timer 5 6 fimen counter wih B bE prescaler Timert
35. ost to the surroundings The value of Qa depends largely on the materials of which the collector is made and its coating and the solar angle of incidence Dixon and Leslie 1979 Practical Points The following points should be noted with regard to the manufacture of flat plate collectors a poor adhesive is often used between the glass covers and the collector box This is because it is preferable to let the pressure inside the collector gap be atmospheric so as to reduce convection and air conduction losses This can only be achieved by not making the covers airtight However as a result dust and moisture penetrate the collector and erode the surface of the absorber plate b insulation materials may contain moisture before they are used in the collector As the collector gets hot this moisture evaporates and condenses on the inside surface of the glass and affects the incident radiation It also corrodes the absorber plate c allowance must be made for glass expansion and the edges of the collector must be beveled so that no rainwater collects on them d the collector should not be used without any liquid inside it Otherwise the high interior temperature generated will cause abnormal expansion that can distort or break the covers e in order to alleviate problems due to the freezing of water in tubes a water ethylene glycol solution can be used f the maximum area of a collector should be 2m2 and g to reduce the amount of
36. rocontroller The microcontroller processes the inputs from the array resistors and crystal The output will be displayed using the 7 segment display 24 Circuit Design Figure 4 shows the circuit diagram of the whole prototype design 5 5 RA4 TOCKI 2 SS SIREO 1 Figure 4 Schematic Diagram of Solar Battery Charger The solar panel that collects and converts the solar energy to electrical energy can be detached from the system This is done to make the prototype easy to carry The prototype has two switches one is for the source selector and the other is for the voltage selector whether it is fixed or variable If the 25 user prefers to use the solar panel as its source for charging the first switch should be turned off open so that the battery is not connected to the system The solar panel must collect enough solar energy to be able to charge a certain device The user still has the option whether he wants to use fixed value of voltage from the solar panel or vary it according to his requirements The second switch is used to connect the system to the voltage regulator that is used to vary the voltage being supplied to the device If the user prefers to use the internal battery the first switch should be turned on close to connect the battery to the system The device cannot be charged if the internal battery has no enough energy Just like the solar panel as a source
37. rode at one edge A sheet of copper is used as a substrate which may be oxidized or sulfided prior to CdS deposition In c the rectifying and ohmic electrodes are deposited as alternate stripes on a glass substrate and overcoated with the CdS Even though the substrate may be transparent it does not need to be and hence this is basically the same Cells of this type have all been relatively inefficient and have series resistance effects While they may have been present they do not appear to have been the major reason It appears that the formation of a junction or barrier to CdS by the use of dry methods usually yields a poor cell 2 Frontwall cells The first frontwall CdS film solar cell was probably made by NADJAKOV though it was probably not recognized as a frontwall cell at the time Photovoltaic action probably occurred only within about a micron s distance from the rectifying metal electrode contact Thus the active area was exceedingly small and accounts for the very low currents obtained The first frontwall cells in the 1 efficiency range were constructed as shown in b with a more or less continuous thin Cu2S layer on the CdS contacted by conductive paint electrode stripes spaced about 3 4mm apart as mentioned earlier 3 Frontwall backwall combination cell If suitable transparent conducting electrodes are used it is evident that the cell could be made in such a manner that it could be illuminated from either or both dire
38. rrupts and clear TOIF Select Bank 1 Set ANO Left Justified Port A O Out 1 11 xxxx TTL 0 0ut 1 In 44 movwf TRISB Port B xxxx TTL movlw 00000000 gt 0 0ut l In movwf TRISC Port C xxxx xxxx schmitt movlw 00000000 O Out l In movwf TRISD Port D xxxx xxxx schmitt movlw B 00000111 O Out 1 In movwf TRISE Port E xxxx xxxx schmitt bcf STATUS RPO Select Bank O0 call Init Var PEE Main call Display call Delay 2 goto Main GE OR EORR BOAR RIKER AK RK E UN BRIAR RPK OK EUR RE EUR CK UN ERR KAER ECKE RR EUR EURO The Interrupt Service Routine RRA IEE BBR AGRO UK XU BIRR BRL FEE IR RDI ARIE BIE ISR routine retfie Return from Interrupt ARERR EK OR Ku ASK UK E ER ORO AUR UU SK OK UR AK COO UK UN BAR UK ASE Seg Table addwf PCL F 2 afbgc de retlw B 00010100 70 retlw B 11010111 21 retlw 01001100 422 45 Init Var retlw retlw retlw retlw retlw retlw retlw retlw retlw retlw retlw retlw clrf bsf bsf bsf movlw movwf clrf call return B 010001 B 100001 B 001001 B 001001 B 010101 B 000001 B 000001 11111111 11111111 11111111 11111111 1111
39. ry Charging Hours with 290mA Supply 37 Capacity Time in hrs Capacity Device Battery Type mAH 380mA Ordinary Rapid Charger Charger Ni Mh AA 2400 15m 3h 30m Nokia BL 5C 600 1h30m 50m Nokia BL 4C 600 1h30m 50m Nokia BL 4C 720 ___ 1 45 55 Noka6015i 950 _ 2h30m 1h 20m Nokia BLD 3 720 1 45 55m Nokia3285 550 1 30 50m Nokia BLS 2N 900 2hl5m 1h 10m Nokia BLB 2 840 _ 2h 15m 1h 10m Nokia BLB 3 1020 _ 2 30 1h 20m Nokia BLC 2 950 2h30m 1h 20m Nokia BMC 2 1020 2h30m 1h 20m Nokia BMC 3 2280 _ 6h 3h LG LGLP AGKM 800 2 10 LG LGLI AGKL 1200 10 HTC Touch XV6900 900 _ 2 15 HTC BTR6900 1100 2h45m HTC BTE6900 1880 5h Ipod battery 60GB 700 50m Ipod battery 30GB 550 1h30m 2 Apple Ipod 4th Gen 950 2h30m m Apple Ipod 3rd Gen 600 1 30 Apple Ipod 1st and 2nd Gen mini series 400 th Apple Ipod 1st and 2nd Gen 1600 4hi5m 5 Asus MyPal PDA Battery 3 7V 1300 3 30 Asus PDA Battery 3 7 1200 3 10 LCD player 1GB mini pocket size Lithium 3hr Table 9 Battery Charging Hours with 380mA Supply No battery rapid charger available 38 Chapter 4 CONCLUSION AND RECOMMENDATION Conclusion A device that could charge AA battery and other devices such as cell phone and MP3 player were created The USB port adaptor was included to provide port to other devices such as MP4 PDAs and other more devices utilizing the same voltage range
40. s already available in the internet provided by the manufacturer of the Microchip Technology Inc for its microcontroller users The microcontroller has its built in converter that served very useful in this research design The on chip debugger that was utilized worked as a special hardware and software for the PIC Microcontroller The PIC Microcontroller that was used design contained a special on chip logic supporting debugging functionality and provided In Circuit Serial Programming capabilities 27 The machine code that was the assembly language compiled using MPASM was burned to the microcontroller and the microcontroller was attached to the system of the design and it functioned as the built in voltmeter Software Component Basically the assembly language and MPASM were used for programming the microcontroller The design team considered the compiler first before the language because there were so many compilers but not all of them were available in market furthermore it was deemed wise to use a compile that was free of change Since the MPASM is free of charge and downloadable the members decided to use assembly language since assembly is the language that the MPASM compiles After programming the program was compiled to machine language and the machine code was burned to the microcontroller System Flowchart Figure 5 shows the system flowchart of the solar battery charger The basic function of this prototype is to charge a
41. sed in a wide range of applications wherever efficient heat dissipation is required Podbieksi 1999 LED Light Emitting Diode is a type of diode that emits light when there is forward current Floyd 2002 PIC Microcontroller Programmable Integrated Circuit is a family of Harvard architecture microcontrollers made by Microchip Technology it is derived from the PIC1640 originaly developed by General Instrument s Microelectronics Division Podbieksi 1999 Photovoltaic module is a packaged interconnected assembly of photovoltaic cells Podbieksi 1999 Potentiometer is a three terminal device that operates on the principle of voltage division It is essentially an adjustable voltage divider As a voltage regulator it is used as a volume or level control on radios TVs and other devices Alexander and Sadiku 2003 Rectifier Diode is a semiconductor device that converts ac into pulsating dc one part of a power supply Floyd 2002 Resistor is the simplest passive element It is a device that has the ability to resist the flow of electric current that is measured in ohms It is usually made from metallic alloys and carbon compounds Alexander and Sadiku 2003 Solar is the energy of the sun Podbieksi 1999 15 Solar Cell is a device that converts solar energy into electricity by the photovoltaic effect Podbieksi 1999 Solar Energy refers to the utilization of the radiant energy from the sun Podbieksi 1999 Toggle Switch
42. the source for charging either solar panel or internal battery and the other that selects if the voltage being supplied is fixed or variable The solar battery was equipped with 7805 voltage regulator that could control the flow of voltage being supplied to the device The PIC microcontroller was used as the voltmeter of the system It could detect the 20 voltage being supplied and could display its value by the use of 3 digit 7 segment display The prototype circuit was created for the whole design and was tested The microcontroller was programmed using assembly language The program was encoded through serial programming and compiled it using the MPASM compiler that is downloadable and free After compiling the machine code was burned to the PIC16F877 Testing and debugging for both programs and electronic circuit were done afterwards Circuit layout was created by photosynthesizing The design was completed by fitting the components inside the casing The solar battery charger was built by following the circuit diagram in Appendix A Hardware Design The whole prototype was basically powered by the solar energy that was collected and converted into electrical energy by the solar panel Once the solar panel collected enough energy to charge the internal battery the battery could be used as the source to charge the device The battery could provide up to 12V to charge a device on the other hand the device could also charge using the
43. wn to be inherently stable thin flexible and relatively straightforward to fabricate There is nothing apparent in the materials required or in the cell design or fabrication methods to indicate that they could not be made in real mass production at very low costs It is appropriate therefore that we consider the possibilities for future improvements and explore potential applications for them Shirland 1966 Conceptual Framework Input Process Solar Panel Internal Battery Switch Solar Energy Microcontroller Voltage Output Device Charging Internal Battery charging Figure 1 Conceptual Framework of the System Figure 1 shows the conceptual framework of the system It shows the inputs that are to be processed to come up with the desired output The two inputs are the switch and the solar energy The switch is used for turning the prototype design ON or OFF The solar energy on the other hand is the source of energy for this research design It is used to charge either the device or the internal battery With the use of these elements the design prototype will activate and is ready to use During the process the solar panel will collect the solar energy and will convert it to electrical energy The electrical energy will be used to charge either the internal battery or the device or both If the user prefers to use the battery as the source for charging the stored power from the battery will transfer to
44. ys 24 2V that is definitely high compared to the voltmeter reading that is 17 5V This result occurred because voltage entering from the solar panel was also consumed by the other components of the system Table 4 on the next page presents the results when the group used the voltage regulator to monitor the voltage being supply to the system and device As expected there was a voltage drop and as the voltage regulator increased its voltage supply the voltage drop also increased Comparatively the voltage reading of built in voltmeter was higher than the reading of the voltmeter used for testing Due to voltage drop that was stated above 32 Using Voltmeter Voltmeter Reading Directly to the Solar Panel Built in Voltmeter Reading 23 9V 24 6V 23 9V 24 9V 24 6V 24 5V 23 7V 25 5V 25 3V 24 9V 24 5V 24 5V 23 9V 23 4V 23 2V 24 9V 24 9V 25 1V 25 1V 25 5V 23 6V 23 7V 24V 24 6V 24 3V 24 9V Table 4 Solar Panel as Source with Variable Value of Voltage Supply 33 Using Voltmeter Voltmeter Reading Directly to the Built in Voltmeter Reading Internal Battery Table 5 Internal Battery as Source with Fix Value of Voltage Supply Just like Table 3 Table 5 shows the difference between the reading of built in VOM and voltmeter and the actual voltage being supplied by the internal battery Still the built in voltmeter displayed higher value that the actual voltmeter used This result occurred becaus
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