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Dhaval Patel


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Dhaval Patel

  1. 1. A Project Report On Enhancement of solar tracking system Submitted in partial fulfillment of the requirements for the degree of Bachelor of Engineering Submitted by PATEL DHAVAL. J (Enr. No. 080350119034, 8th Sem, ME.) PATEL HARDIK.N (Enr. No. 080350119035, 8th Sem, ME.) PATEL NISHIT.K (Enr. No. 080350119038, 8th Sem, ME.) under the guidance of Internal GuideAsst. Prof. KALPESH PARMAR (M. E. Dept.) Submitted to Noble Group of Institutions-Junagadh Mechanical Engineering Department Year 2011-2012
  2. 2. Noble Group of institutions Junagadh CERTIFICATEThis is to Certify that Mr. / Miss ………………………………….Enrollment No………………… of B.E. ……… Semester of Mechanical Engineering hassatisfactorily completed his/her project work for partial fulfillment forthe duration of …………………. to ………………….. Guided By Head of Department(Mr. KALPESH PARMAR) (Mr. V.T. Shekhada) ( Mechanical Engineering Department) Date:-07/04/2012
  3. 3. Acknowledgement Many people have contributed to this work and have made it possible for us to escapewith what little sanity remains. I would like to thank Mr. Kalpesh parmar, our advisor for theduration, for supporting us during our time. He has provided direction and opinion groundedin the reality that We all too often allow to pass by the wayside in our quest for solutions. Hehas also been a friend and mentor and we sincerely hope we find opportunities in the future towork together once again. We would also like to extend my thanks to Mr. B.N.Modi, the manwho has taught us the importance of written and oral communication skills in the engineeringprofession. Further, his outlook on life has been inspiring and at times, frightening. He, aboveall, exemplifies the importance maintaining a realistic opinion of the importance of yourwork; it keeps you honest.=
  4. 4. AbstractSolar energy is rapidly gaining notoriety as an important means of expanding renewableenergy resources. As such, it is vital that those in engineering fields understand thetechnologies associated with this area. My project will include the design and construction ofa microcontroller-based solar panel tracking system. Solar tracking allows more energy to beproduced because the solar array is able to remain aligned to the sun. This system builds upontopics learned in this course. A working system will ultimately be demonstrated to validatethe design. Problems and possible improvements will also be presented.
  5. 5. PREFACE ` The mechanical engineering is well structured and integrated course of engineeringstudies. The main objective of Industrial Define Problem (IDP) is to develop skill in studentby supplement to the theoretical study. Industrial training helps to gain real life knowledgeabout the industrial environment, manufacturing practices and to develop skill aboutindustrial problem. In every professional course, IDP is an important factor. Professors give us theoreticalknowledge of various subjects in the college but we are practically exposed of such subjectswhen we get the project in the organization. It is only the project through which I come toknow that what an industry is and how it works and how to problem can be solved. I canlearn about various departmental operations being performed in the industry, which would, inreturn, help me in the future when I will enter the practical field. During this whole project I got a lot of experience and came to know about themanufacturing process and industrial problems in real that how it differs from those oftheoretical knowledge and the practically in the real life. In today’s globalize world, where cutthroat competition is prevailing in the market,theoretical knowledge is not sufficient. Beside this one need to have practical knowledge,which would help an individual in my carrier activities and it is true that “Experience is best teacher”.
  8. 8. 1. IntroductionRenewable energy solutions are becoming increasingly popular. Photovoltaic (solar) systemsare but one example. Maximizing power output from a solar system is desirable to increaseefficiency. In order to maximize power output from the solar panels, one needs to keep thepanels aligned with the sun. As such, a means of tracking the sun is required. This is a farmore cost effective solution than purchasing additional solar panels. It has been estimatedthat the yield from solar panels can be increased by 30 to 60 percent by utilizing a trackingsystem instead of a stationary array [1]. This project develops an automatic tracking systemwhich will keep the solar panels aligned with the sun in order to maximize efficiency.This paper begins with presenting background theory in light sensors and stepper motors asthey apply to the project. The paper continues with specific design methodologies pertainingto photocells, stepper motors and drivers, microcontroller selection, voltage regulation,physical construction, and a software/system operation explanation. The paper concludeswith a discussion of design results and future work.
  9. 9. 2. Review of project. Solar power production is one of the applications which require high initial cost. Theobject behind the project was to make some system which can increase the effectiveness ofthe solar PV panel.The power produced by the solar panel depends upon two factors. 1. Intensity of solar rays. 2. Angle of incidence. The intensity of solar rays depends on weather condition which include seasonal effect of cloud etc. this factor is not in our control and entirely depend on position on earth. Solar panel can give its maximum output when the plate is placed exactlyperpendicular to solar rays to achieve this be tried to make an automatic system that track thesun . The first attempt was to make the solar tracker with the help of DC motor and geartrain system but we could not achieve it due to following reason. To make a gear train system is costly and also complicated to design compare tosimple belt and pulley arrangement also the min.rpm. available with DC motor will make thegear size very large and to make big size gear is not feasible. Another problem encounteredwith DC motor was to put the system at its initial position at the next day. To avoid this problem we use a stepper motor and belt pulley arrangement theadditional part required are driving circuit and microcontroller circumventing the cost of itthis system is more sophisticated and less complex also easy to assemble
  10. 10. 3. Evolution of Solar TrackerSince the sun moves across the sky throughout the day, in order to receive the best angle ofexposure to sunlight for collection energy. A tracking mechanism is often incorporated intothe solar arrays to keep the array pointed towards the sun.A solar tracker is a device onto which solar panels are fitted which tracks the motion of thesun across the sky ensuring that the maximum amount of sunlight strikes the panelsthroughout the day. When compare to the price of the PV solar panels, the cost of a solartracker is relatively low.Most photovoltaic (PV) solar panels are fitted in a fixed location- for example on the slopingroof of a house, or on framework fixed to the ground. Since the sun moves across the skythough the day, this is far from an ideal solution.Solar panels are usually set up to be in full direct sunshine at the middle of the day facingSouth in the Northern Hemisphere, or North in the Southern Hemisphere. Therefore morningand evening sunlight hits the panels at an acute angle reducing the total amount of electricitywhich can be generated each day.
  11. 11. 4. System DesignAt the beginning of the project, the student and faculty advisor agreed to the following designrequirements:_ Must track the sun during daylight hourso During the time that the sun is up, the system must follow the sun’s position in the sky.o This must be done with an active control, timed movements are wasteful._ Self powered, must be fully autonomouso The system must operate on, and charge its own battery supply_ Semi-permanent installation on the flat roof of a buildingo A base must be designed to allow installation without fasteners onto a flat section of roof_ Weather resistanto This system will be designed to be fully functional outdoors and resist any wind andweather complications._ Remote instrumentation to monitor statuso A method will be implemented to allow the system to be monitored remotely.The major components of this system are as follows. Each component required the student tomake decisions that would ultimately affect the final design, based on both technical as wellas financial constraints._ The solar panel that will convert the radiation of the sun into electricityo The solar panel in direct sunlight is capable of sourcing 23V under open circuitconditions, and approximately 0.75A under short circuit conditions. The solar panelused in this project was already available and therefore did not cost any moneytowards the project.
  12. 12. _ A base to support the solar panel.oThe base must be able to mount with no fasteners on a flat roof. It must also be large enoughand heavy enough to provide a solid mounting point that will prevent the system from beingdamaged by strong winds._ A weather-resistant housing to protect the electronicso The final control box had two parts (bottom and top). The interface between the twoincluded a gasketed design for water-resistance._ A motor to move the solar panel as the sun traverses through the skyo The intent of the project was to automatically rotate the solar panel to orient the panelperpendicular to the sun’s rays.o An antenna rotor was chosen because of its inherent robustness.o The antenna rotor requires 30Vac to operate. An inverter (12Vdc – 120Vac) and atransformer were employed to convert the dc from the batteries/solar panel to a 30volt modified sine wave ac power source._ Electronics to sense the sun’s position, and determine whether the solar panel needs tomoveo The approach employed to orient the panel with the sun was to find the point thatmaximized the amount of power being converted by the panel. Current was measuredthrough a fixed resistance to determine the power consumed.o An 8051 microcontroller would be the brains of the operation, sensing which positionof the panel yielded maximum power, and sending signals to the antenna motor tomove the solar panel accordingly._ A set of two 6V lead-acid batteries, connected in series, that will be charged up during theday by the solar panelo The lead-acid batteries were already available and therefore did not cost any moneytowards the project.
  13. 13. The basic operation of the system is as follows:_ The solar cell operates as a current source with current being proportional to light intensity._ Current measurement is performed at 3 different points of rotation, and the systemrepositions to the position which provides the greatest power._ The Earth rotates 5 degrees per 20 minutes._ The control software includes a 15 minute delay between measurement routines.o The increment of movement is chosen as 5 degrees._ A low light level sensor disables the movement controls; this prevents battery rundownwhilelooking for the sun in low light conditions.o This will also provide a night-time idle state._ After sundown the panel will be facing west. To facilitate a system reset to face east, a 24hour timer is incorporated that will drive the panel to the east every morning at dawn.o To allow the system’s 24hour timer to work properly, the system must be initializedat dawn._ The rotor’s base must be initially positioned with the back of the rotor facing north. Thesystem will not operate correctly otherwise.
  14. 14. 5. Solar TrackerSolar Tracker is basically a device onto which solar panels are fitted which tracks the motionof the sun across the sky ensuring that the maximum amount of sunlight strikes the panelsthroughout the day. After finding the sunlight, the tracker will try to navigate through thepath ensuring the best sunlight is detected.The design of the Solar Tracker requires many components. The design and construction of itcould be divided into six main parts, each with their main function. They are:1. Methods of Tracker2. Methods of Drives3. Sensor and Sensor Controller4. Motor and Motor Controller5. Tracker Solving Algorithm6. Data Acquisition/Interface CardThe six main parts would need to work together harmoniously to achieve a smooth run for theSolar Tracker. I shall explore their functions individually in the next section. ar tracker andless solar panels ..
  15. 15. 6. TYPES OF SOLAR TRCKER. Single axis solar trackersSingle axis solar trackers can either have a horizontal or a vertical axle. The horizontal type isused in tropical regions where the sun gets very high at noon, but the days are short. Thevertical type is used in high latitudes where the sun does not get very high, but summer dayscan be very long. a Solar Tracker using horizontal axle. The single axis tracking system is thesimplest solution and the most common one used. Tracker using horizontal axle
  16. 16. Double axis solar trackersDouble axis solar trackers have both a horizontal and a vertical axle and so can track theSuns apparent motion exactly anywhere in the World. Figure 4 shows a Solar Tracker usinghorizontal and vertical axle. This type of system is used to control astronomical telescopes,and so there is plenty of software available to automatically predict and track the motion ofthe sun across the sky By tracking the sun, the efficiency of the solar panels can be increasedby 30-40%.The dual axis tracking system is also used for concentrating a solar reflectortoward the concentrator on heliostat systems.Tracker using both horizontal and vertical axle
  17. 17. ACCORDING TO METHOD OF DRIVE1. Active Trackers Active Trackers use motors and gear trains to direct the tracker as commanded by acontroller responding to the solar direction. Light-sensing trackers typically have two photosensors, such as photodiodes, configured differentially so that they output a null whenreceiving the same light flux. Mechanically, they should be unidirectional (i.e. flat) and areaimed 90 degrees apart. This will cause the steepest part of their cosine transfer functions tobalance at the steepest part, which translates into maximum sensitivity.2. Passive Trackers Passive Trackers use a low boiling point compressed gas fluid that is driven to oneside or the other (by solar heat creating gas pressure) to cause the tracker to move in responseto an imbalance.3. Chronological Tracker Chronological Tracker counteracts the earths rotation by turning at an equal rate asthe earth, but in the opposite direction. Actually the rates arent quite equal, because as theearth goes around the sun, the position of the sun changes with respect to the earth by 360°every year or 365.24 days.
  18. 18. 7. SUN’S APPARENT MOTIONDuring the day the sun appears to move across the sky from left to right and up and downabove the horizon from sunrise to noon to sunset. Figure shows the schematic above of theSuns apparent motion as seen from the Northern Hemisphere.To keep up with other green energies, the solar cell market has to be as efficient as possiblein order not to lose market shares on the global energy marketplace. There are two main waysto make the solar cells more efficient, one is to develop the solar cell material and make thepanels even more efficient and another way is to optimize the output by installing the solarpanels on a tracking base that follows the sun.The end-user will prefer the tracking solution rather than a fixed ground system to increasetheir earnings because: The efficiency increases by 30-40% The space requirement for a solar park is reduced, and they keep the same output
  19. 19. 8. Description of parts used Technology of Solar Panel Solar panels are devices that convert light into electricity. They are called solar after thesun or "Sol" because the sun is the most powerful source of the light available for use. Theyare sometimes called photovoltaic which means "light-electricity". Solar cells or PV cells relyon the photovoltaic effect to absorb the energy of the sun and cause current to flow betweentwo oppositely charge layers. A solar panel is a collection of solar cells. Although each solar cell provides a relativelysmall amount of power, many solar cells spread over a large area can provide enough powerto be useful. To get the most power, solar panels have to be pointed directly at the Sun. The development of solar cell technology begins with 1839 research of French physicistAntoine-Cesar Becquerel. He observed the photovoltaic effect while experimenting with asolid electrode in an electrolyte solution.
  20. 20. According to Encyclopedia Britannica the first genuine for solar panel was built around1883 by Charles Fritts. He used junctions formed by coating selenium (a semiconductor) withan extremely thin layer of gold. Crystalline silicon and gallium arsenide are typical choices of materials for solarpanels. Gallium arsenide crystals are grown especially for photovoltaic use, but siliconcrystals are available in less-expensive standard ingots, which are produced mainly forconsumption in the microelectronics industry. Norway’s Renewable Energy Corporation (REC) has confirmed that it will build asolar manufacturing plant in Singapore by 2010 - the largest in the world. This plant will beable to produce products that can generate up to 1.5 giga watts (GW) of energy every year.That is enough to power several million households at any one time. Last year, the world as awhole produced products that could generate just 2 GW in total. Bearing. A bearing is a device to allow constrained relative motion between two parts typicallyrotation or linear movement. Bearings may be classified broadly according to the motion theyallow and according to their principle of operation as well as by the direction applied loadsthey can handle.Why use this bearing?Because of rolling contact , lower friction than any other type. Ensures smooth operation. Ease of operation. Low cost.
  21. 21. Pulley A pulley is mechanism composed of a wheel with a grove between two flangesAround the wheel’s circumference. A rope ,cable or belt usually runs inside the grove.Pulley are used to change direction of an applied force,transmit rotational motion,or realize amechanical advantage in either a linear or rotational system of motion. Here we use pulley because of following advantage. Drive is positive because sleep between the belt and the pulley grooves isnegligible. Smooth drive. Easy install and remove. Easy to manufacture on small basis
  22. 22. Power SupplyThe power supply is provided by 1 pack of eight numbers of 1.2V, 1600mAH NiMHrechargeable batteries. The total power supply to the stepper motor to operate is 9.6V whichis higher than the 5V for the EMANT300 digital output. Figure 24 shows a pack of eightnumbers of 1.2V, 1600mAH NiMH rechargeable batteries.
  23. 23. 9. description of electrical parts Motors.Motors are use to drive the Solar Tracker to the best angle of exposure of light. For thissection, we shall look at some of the motor types available on the market.1. Stepper MotorsStepper motor has relatively limited power which means that wheelspin will not be aproblem. It is not fast but it will work. The driver chips are operated by two signals. Onesignal determines the direction of rotation, plus for forward and minus for backwards. Theother moves the stepper by one step each time it goes from minus to plusStepper motors move in steps, 200 or 400 steps per revolution to be precise. To move them,the stepper driver firmware had to have a smooth pulse. If the pulse timing is out, the motorwould just stop and not move. They can also produce precise motor rotation if the correctmotor driver firmware signals are obtained.
  24. 24. 2. DC MotorsDC motors are cheaper to buy, and simple to drive but they need feed-back sensors to allowcontrol of the speed. It is necessary to detect the rotation of the wheels, usually by means ofsensors better controlled by pulling the motor supply that uses less battery power than theanalogue/resistor methods. Low-inertia, efficient servo-motors bring advantages of fastresponse and efficiency, but add cost .The advantages of the DC motor are the torque and their speed is easier to control. Thedrawbacks of DC motors are that they consumed huge amounts of power. They wouldconsumed the battery power in no time and power saving techniques must be employed toensure the mouse do not stop halfway while navigating. They are also prone to dust andharder to maintain.DC MOTOR
  25. 25. 3. Servo Motors Servos contain a small DC motor, a gearbox and some control circuitry, and feed on 5volts at about 100mA maximum, and about 10-20mA when idle. They have a three-wireconnector, one common wire (0 volt, usually black), one +5v wire (usually red), and onesignal wire. In normal use they are controlled by pulses of about 1 to 2 milli-seconds at arepetition rate of about 50 per second. A short pulse makes the servo drive to one end of the travel, a long pulse makes itdrive to the other end, and a medium one puts it somewhere proportionally between. Someservos have gear components that allow them to rotate continuously. This method needs theservo to have a feedback potentiometer used by internal circuits to measure the position ofthe output shaft. If this is disconnected and the wires taken to an external pre-setpotentiometer, the servo will drive continuously in one direction if fed with short pulses andvice-versa. If there are no pulses, the servo stops. It is uses to drive the Solar Tracker Eastwardand Westward. The pulses are at normal TTL levels. The speed though, is not greatly affectedby the pulse repetition rate, as long as it is above about 30 per second. These pulses can easilybe provided by an output port of just about any computer, for instance the data or controllines of a printer port or a serial port, or a simple addressed latch added to the memorycircuits. A possible configuration is the tricycle described above, with one driving andsteering-wheel at the front and two idler wheels at the rear. Using a Radio Controlled (RC) servo for steering is a good method, because theposition of the steering mechanism is determined by the length of the servo drive pulse,which can be generated by a software countdown loop or a hard-ware counter. If an RC servois used as a drive motor, wheel motion sensors are needed on at least one wheel as in any DCmotor
  26. 26. SensorsA sensor is a device that measures a physical quantity and converts it into a signal which canbe read by an observer or by an instrument.1. Light Dependent Resistor Light Dependent Resistor (LDR) is made of a high-resistance semiconductor. It canalso be referred to as a photoconductor. If light falling on the device is of the high enoughfrequency, photons absorbed by the semiconductor give bound electrons enough energy tojump into the conduction band. The resulting free electron (and its hole partner) conductelectricity, thereby lowering resistance. Hence, Light Dependent Resistors (LDR) is veryuseful in light sensor circuits. LDR is very high-resistance, sometimes as high as 1000 000Ω,when they are illuminated with light resistance drops dramatically. Photodiode (BPW34) is a light sensor which has a high speed and high sensitivesilicon PIN photodiode in a miniature flat plastic package. A photodiode is designed to beresponsive to optical input. Due to its water clear epoxy the device is sensitive to visible andinfrared radiation. The large active area combined with a flat case gives a high sensitivity at a wideviewing angle. Photodiodes can be used in either zero bias or reverse bias. In zero bias, lightfalling on the diode causes a voltage to develop across the device, leading to a current in theforward bias direction. This is called the photovoltaic effect, and is the basis for solar cells -in fact a solar cell is just a large number of big, cheap photodiodes. Diodes usually haveextremely high resistance when reverse biased. This resistance is reduced when light of anappropriate frequency shines on the junction. Hence, a reverse biased diode can be used as a detector by monitoring the currentrunning through it. Circuits based on this effect are more sensitive to light than ones based onthe photovoltaic effect.
  27. 27. Sensing around the trackerThe sensors work on a system of two photodiodes comparator circuit. the circuit diagram ofEast Light Intensity and West Light Intensity respectively. Photodiodes (BPW34) can be used in either zero bias or reverse bias. Diodes have extremely high resistance when reverse biased. This resistance is reduced when light of an appropriate frequency shines on the junction. Hence, a reverse biased diode can be used as a light detector by monitoring the current running through it. Coupled to a 10KΩ resistor, and given the specification of the BPW34 a simple relationship between light intensity and the voltage is given by:Light intensity = 2400 × V o= 2400 × 2.5V= 6000 luxThe human eye is a very poor “instrument” for measuring light intensity, because the pupiladjusts constantly in response to the amount of light it receives. To accurately measure thelight intensity in a given spot, it is best to use a light meter. Light intensity may be measured in lux (metric system) or foot-candles (Imperial system). Note that 1 foot-candle = 10.76 lux Motion Control A common stepper motor is the four-coil unipolar. They are called unipolar because theyrequire only that their coils be driven on and off. The stepping sequence for a four-coilunipolar steppers is shown on table 4 below.Stepping sequence for a four‐coil uni polar steppersThe motor’s speed depends on how fast the controller runs through the step sequence.
  28. 28. The stepper motor I have used is the PF443-03A from Mycom. It requires a supply voltage of12V and the coil current is 0.31A. Each step is 1.8 degrees.The EMANT300 digital output current drive is about 20mA – too low to drive the steppermotor coil. Besides, the Mycom PF443 stepper motor operates from a 12V supply which ishigher than the 5V allowed for the EMANT300 digital output. Therefore, one simple solutionis to add the ULN2003. Figure 22 shows the pin configuration of ULN2003. It is a highvoltage, high current darlington driver comprising seven NPN darlington pairs. All featureintegral clamp diodes for switching inductive loads. The ULN2003 has a maximumsustaining output voltage of 50V and maximum output current of 0.5A per channel whicheasily exceeds the requirements of the
  29. 29. 10. DESIGN CONSIDERATION. Supporting table:Two layer design, to avoid following:Shaft bendingShaft vibrationRigid support Thickness of plate is selected such that: Bearing can be located and fixed in it easily. To support weight Dimension is selected such that whole thing can be accommodating in it easily. Shaft:Length is selected: Based on table heightTo allow rotation solar panel without interferenceDiameter selected: Based on weight of solar plate Shaft material Hollow shaft to reduce of shaft Bearing:
  30. 30. Based on shaft diameter Based on amount of load to be taken by it. Pulley:Thickness : based on belt width. Outer diameter: torque required to transmit. Inner diameter: based on main shaft diameter and motor shaft diameter. Groove is provided to avoid slippage . Stepper motor: Torque required to transmit. Very slow movement of shaft required.Minimum power consumption. Bolt:Length: based on motor height.Diameter: based on hole of motor base. Center distance between main shaft and motor shaft:Based on pulley outer diameter . To avoid interference between wire ,pulley and main shaft.
  31. 31. Belt:Length: center distance between motor and main shaft.v-belt: to avoid slippage. u-shape joint:To allow joint between main shaft and panel To allow easy fixing and dismantle To allow orientation of plate depending of sun position
  32. 32. 11. Specification of parts Solar panelModule type: PE 1210Rated power :pmax: 6 wattsV avg: 12 voltCurrent I avg: 0.6 ampsVoc: 17 voltCurrent (max)sc: 0.7amprSize: 30*45(cm) Dc motor:Type:Volt:Current:Torque:Step per evolution:Step angle:Shaft diameter: Bearing:Type:Inner diameter:Out diameter:Material:No:
  33. 33. Pulley:Type:Outer diameter:Inner diameter 1:Inner diameter 2:Width:Groove width:Material: Shaft:Type:Inner diameter:Outer diameter:Length:Material: Belt:Type:Diameter:Length:Material:
  34. 34. Stand:Type:Length:Width:Plate thickness:Leg cross-section:Gap between plate:Material: Bolt:Diameter:Length:No:Material:
  35. 35. 12. ASSEMBLY TECHNIQUEFirst of all motor is fixed on wooden base with help of bolts and nuts.One aluminium pulley is fixed onto the motor shaft using adhesive material.Bearings are fixed in the groove of both wooden plate.Another pulley is fixed on main shaft and locate at appropriate position on it .Shaft is inserted on bearing.Both pulley must placed on same horizontal plane.Connect both pulley with help of belt and belt should be enough tight to avoidslippage.Fix the solar panel at the top of main shaft with help of knuckle joint.Keep appropriate angle of panel according to sun position.Connect the stepper motor with the controller circuit with the battery.
  36. 36. 13. Working principle Sun is the source of energy. This energy is in form of electromagnetic wave strikes onto the solar panel. Which convert solar energy into electrical energy.Power output from the panel is stored into the rechargeable batteries.There batteries, each of six volt are use, which are connected in seriesOut of three batteries two battery are connected across the stepper motor through controllercircuit.Electrical energy supplied to the motor is converted into the mechanical rotation of shaft. As pulley is provided on shaft it will rotate and transmit the motion to another pulleyto provided on main shaft through belt.
  37. 37. Structure of Solar TrackerThe structure of my Solar Tracker is based on the horizontal-axle Solar Tracker method. , the overview, top view and side view respectively where all the components are place.
  38. 38. 14.Programming Language for the Solar Tracker The program which I have chosen to run this Solar Tracker Algorithm is LabVIEW. Itis a programming language from National Instruments, also referred to a VI (VirtualInstrument), consists of two windows: the Front Panel and the Block Diagram. It is agraphical language in which the program is drawn rather than written. There is no text-basedcode like in Basic or C. The program is presented as a diagram with data flow determiningthe sequence of the program Lab VIEW uses its own National Instruments Data Socket technology to share livedata with other VI on the Web. The Lab VIEW Web Server is use to create HTMLdocuments, publish front panel images on the Web, and embed VI in a Web page. It alsocontrols browser access to the published front panels and configures which VIs are visible onthe Web. Protocols that are use include the HTTP and TCP/IP and are dependable on theapplication. A plug-in package called the Lab VIEW Run-Time Engine is needed to accessthe Lab VIEW applications .Other programming languages like the Java, Pearl,Microprocessor and C++ could also be used to write the software.
  39. 39. Solar Tracker – Solving AlgorithmThe main objective of the Solar Tracker Algorithm is to quickly determine to the best angleof exposure of light from the sun. A pair of sensors is used to point the East and West of thelocation of the light. Figure shows a flow chart of Solar Tracker Algorithm.
  40. 40. Program in c language for solar tracking system:#Include<reg51.h>Void delay(void);Void delay1(void);Void main(){ unsigned char l=0;TO COUNT THE NUMBER OF STEPS MOVED.While(l<180) {p0=0xaa;STARTS Delay l(); P0=0x66; Delay l(); P0=0x55; Delay 1 (); P0=0x99;
  41. 41. Delay1(); L=l+4}Delay l();Delay 1();Delay 1();L=0;While(l<180)ROTATION STARTS.{p0=0xaa;Delay l();P0=ox99;Delay l();P0=ox55;Delay l();
  42. 42. P0=ox66;Delay l();1=1+4;}1=o;ROTATION ENDSDelay();While(1<=100)ROTATION STARTS{P0=0xaa;Delay();MINUTESP0=0x99;Delay();P0=0x55;Delay();P0=0x66;
  43. 43. Delay();1=1+4;}While(1<=100);{p0=0xaa;Delay1();P0=0x99;Delay1();P0=0x55;Delay1();P0=0x66;Delay1();1=1+4;}}Void delay(void){
  44. 44. Unsigned char x,t,u,y;For(x=0;x<=200;x++){For(y=0;y<=280;y++){for(t=0;t<=290;t++){for(u=0;u<=200;u++);}}}}Void delay1(void){Unsigned char x ,y;For(x=0;x<=110;x++){for(y=0;y<=110;y++);}
  45. 45. 15. Analysis and Perception To simulate interest in young professionals and students in solar, solar competitionsare held worldwide annually. Of particular interest would be the Solar Tracker competitionthat saw professionals and students taking part. This competition sees solar panels are fittedwhich tracks the motion of the sun across the sky ensuring that the maximum amount ofsunlight strikes the panels throughout the day and complete the best sunlight that it absorbed.The six main functions of a Solar Tracker are the methods of tracker mount, drives, sensors,motors, data acquisition/interface card and the Solar Tracker solving algorithm. There are a few methods of tracker mount and drive that is available for use. Each ofthe methods had their advantages and disadvantages. Of particular interest would be thesingle-axis and active tracker method as it is symmetric placements and turnings of themotor. The eyes of the Solar Tracker are taken care by the photodiodes. The photodiodes areimportant because it is use to detect the amount of light intensity. Different motors are available on the market to drive the mouse as reviewed. The servo motors are highly recommended as they have precise motor movements and consume power only when moving. One thing that would turn against them would be the cost they bring to the project. As for the DC motors, although they are easy to control and cheaper to buy, they consumed lots of power and are harder to maintain. Stepper motors are cheap and able to control precise rotations of the motor through software The feedback of the solar tracker depends on the interface card. The processor needs to have adequate ports for the input signals to make decisions in real time. The interface card must also not consume too much power from the batteries as to conserve energy. The programming language which I have chosen shall be one that must be easy to use and a new challenge to me. For the power supply, I would need power that is able to operate the stepper motor.Rechargeable NiMH batteries would be suitable as they could be recharge quickly and do nothold up too much space
  46. 46. Applications of the Proposed Project Solar energy refers primarily to the use of solar radiation for practical ends. However, all renewable energies, other than geothermal and tidal, derive their energy from the sun. Solar technologies are broadly characterized as either passive or active depending on the way they capture, convert and distribute sunlight. Active solar techniques use photovoltaic panels, pumps, and fans to convert sunlight into useful outputs. Passive solar techniques include selecting materials with favorable thermal properties, designing spaces that naturally circulate air, and referencing the position of a building to the Sun. Active solar technologies increase the supply of energy and are considered supply side technologies, while passive solar technologies reduce the need for alternate resources and are generally considered demand side technologies. Solar tracking system will help us utilize every bit of solar energy in most efficient way.Block Diagram of the Proposed SystemExplanation of Each Component in Block Diagram
  47. 47. Microcontroller: - This is the heart of the circuit which performs all commanding andcontrolling operations. Microcontroller now days are becoming more popular because ofseveral advantages over microprocessor. As it reduces the requirement of additionalinterfacing IC those are needed in microprocessor, the data which has to be read andcontrolled is directly fed to microcontroller and the software is designed in accordance withthe requirement for controlling the circuit and action is taken by proper output device.Sensors: - Here we would be using two LDR sensors in two different directions to sense thedirection of maximum intensity of light. The difference between the outputs of the sensors isgiven to the microcontroller unit.Oscillators:-Two oscillators would be used for generating square waves. The sensors areconnected to these two oscillators which generate square pulses in accordance to the intensityof the light falling on the two sensors. The outputs of these two oscillators are given to themicrocontroller for comparison.Stepper Motor:- A uni-polar stepper motor is being used for rotation in one direction only.The stepper motor covers an angle of 1.8 degrees per step. The output of the microcontrolleris given to this motor through motor driver circuit and hence the motor is rotated accordingly,pointing in the direction of maximum intensity of sunlight.Motor Driver:- The uni-polar motor driver circuit is used for controlling the rotation of thestepper motor. This circuit has transistors in darlington pair with free-wheeling diodes.
  48. 48. 89c51 microcontroller hardware
  49. 49. 89C52:- Here microcontroller IC 89C52 used is a 40 pin IC consists of four ports which areused as an input and output port. This is the heart of the circuit which performs allcommanding and controlling operations. Microcontroller now days are becoming morepopular because of several advantages over microprocessor. As it reduces the requirement ofadditional interfacing IC those are needed in microprocessor, the data which has to be readand controlled is directly fed to microcontroller and the software is designed in accordancewith the requirement for controlling the circuit and action is taken by proper output device.LDRs:- For sensing the maximum intensity of light LDR sensors are used. Here we would beusing two LDR sensors in two different directions to sense the direction of maximumintensity of light. The difference between the outputs of the sensors is given to themicrocontroller unit.555:- For generating square pulses ICs 555 are used as oscillators. Two oscillators would beused for generating square waves. The sensors are connected to these two oscillators whichgenerate square pulses in accordance to the intensity of the light falling on the two sensors.The outputs of these two oscillators are given to the microcontroller for comparison.Power Supply: - There are two power supply used to give power to the circuits. The firstpower supply is 5v regulated power supply it is used to supply power to microcontroller andsensing circuits. The second power supply is used to give the 5v power to motor.Motor Driver:-For configuration in darlington pair four TIP122 transistors and four 1N4110diodes are being used in order to increase the current gain that is required to drive the steppermotor.
  53. 53. Comparision of solar tracking system to simple solar systemwith graph
  54. 54. 16. Conclusion This project had been a great learning experience. Apart from engineering skills, Ialso learnt time management skills, project management skills and experience in starting aproject which I had no idea about. I believe that I have done well with all the constraints. I am a part time student fromdifferent working backgrounds and experiences. Although lacking in the expertise of solartracker, I’m still manage to complete the individual parts.