A Project Report On

Enhancement of solar tracking system

Submitted in partial fulfillment ofthe requirements for the degree of

Bachelor of Engineering

Submitted byPATEL 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 Guide Asst. Prof. KALPESH PARMAR (M. E. Dept.)

Submitted to

Noble Group of Institutions-JunagadhMechanical Engineering Department

Year 2011-2012

Noble Group of institutions

Junagadh

CERTIFICATE

This is to Certify that Mr. / Miss ………………………………….Enrollment No

………………… of B.E. ……… Semester of Mechanical Engineering has

satisfactorily completed his/her project work for partial fulfillment for

the duration of …………………. to …………………..

Guided By Head of Department

(Mr. KALPESH PARMAR) (Mr. V.T. Shekhada)

( Mechanical Engineering Department)

Date:-07/04/2012

Acknowledgement

Many people have contributed to this work and have made it possible for us to escape

with what little sanity remains. I would like to thank Mr. Kalpesh parmar, our advisor for the

duration, for supporting us during our time. He has provided direction and opinion grounded

in the reality that We all too often allow to pass by the wayside in our quest for solutions. He

has also been a friend and mentor and we sincerely hope we find opportunities in the future to

work together once again. We would also like to extend my thanks to Mr. B.N.Modi, the man

who has taught us the importance of written and oral communication skills in the engineering

profession. Further, his outlook on life has been inspiring and at times, frightening. He, above

all, exemplifies the importance maintaining a realistic opinion of the importance of your

work; it keeps you honest.

=

Abstract

Solar energy is rapidly gaining notoriety as an important means of expanding renewable

energy resources. As such, it is vital that those in engineering fields understand the

technologies associated with this area. My project will include the design and construction of

a microcontroller-based solar panel tracking system. Solar tracking allows more energy to be

produced because the solar array is able to remain aligned to the sun. This system builds upon

topics learned in this course. A working system will ultimately be demonstrated to validate

the design. Problems and possible improvements will also be presented.

PREFACE

`

The mechanical engineering is well structured and integrated course of engineering studies. The main objective of Industrial Define Problem (IDP) is to develop skill in student by supplement to the theoretical study. Industrial training helps to gain real life knowledge about the industrial environment, manufacturing practices and to develop skill about industrial problem.

In every professional course, IDP is an important factor. Professors give us theoretical knowledge of various subjects in the college but we are practically exposed of such subjects when we get the project in the organization. It is only the project through which I come to know that what an industry is and how it works and how to problem can be solved. I can learn about various departmental operations being performed in the industry, which would, in return, 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 the manufacturing process and industrial problems in real that how it differs from those of theoretical 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”.

INDEX

1. INTRODUCTION

2. REVIEW OF PROJECT

3. EVOLUTION OF SOLAR TRACKER

4. SYSTEM DESIGN

5. SOLAR TRACKER

6. TYPES OF SOLAR TRACKER

SINGLE AXIS SOLAR TRACKER DOUBLE AXIS SOLAR TRACKER ACTIVE TRACKER PASSIVE TRACKER CHRONOLOGICAL TRACKER

7. SUN’S APPARENT MOTION

8. DESCRIPTION OF PARTS USED

TECHNOLOGY OF SOLAR PANEL BEARINGS PULLEY POWER SUPPLY

9. DESCRIPTION OF ELECTRICAL PARTS

STEPPER MOTOR SERVO MOTOR DC MOTOR SENSOR MOTION CONTROL

10. DESIGN CONSIDERATION

SUPPORTING TABLE SHAFT BEARING PULLEY

STEPPER MOTOR BOLT CENTER DISTANCE BETWEEN MAIN SHAFT AND MOTOR SHAFT BELT U-SHAPE JOINT

11. SPECIFICATION OF PARTS

SOLAR PANEL STEPPER MOTOR BEARING PULLEY SHAFT BELT STAND BOLT

12. ASSEMBLY TECHNIQUE13. WORKING PRINCIPLE

STRUCTURE OF SOLAR TRACKER

14. PROGRAMMING LANGUAGE FOR THE SOLAR TRACKER

SOLAR TRACKER ALGORITHM PROGRAM IN C-LANGUAGE FOR SOLAR TRACKER SYSTEM

15. ANALYSIS AND PERCEPTION

APPLICATION OF THE PROPOSED PROJECT COMPARISON OF SOLAR TRACKING SYSTEM TO SIMPLE SOLAR SYSTEM

16. CONCLUSION

17. REFERANCE

1. Introduction

Renewable energy solutions are becoming increasingly popular. Photovoltaic (solar) systems

are but one example. Maximizing power output from a solar system is desirable to increase

efficiency. In order to maximize power output from the solar panels, one needs to keep the

panels aligned with the sun. As such, a means of tracking the sun is required. This is a far

more cost effective solution than purchasing additional solar panels. It has been estimated

that the yield from solar panels can be increased by 30 to 60 percent by utilizing a tracking

system instead of a stationary array [1]. This project develops an automatic tracking system

which 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 as

they apply to the project. The paper continues with specific design methodologies pertaining

to photocells, stepper motors and drivers, microcontroller selection, voltage regulation,

physical construction, and a software/system operation explanation. The paper concludes

with a discussion of design results and future work.

2. Review of project.

Solar power production is one of the applications which require high initial cost. The

object behind the project was to make some system which can increase the effectiveness of

the 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 exactly

perpendicular to solar rays to achieve this be tried to make an automatic system that track the

sun .

The first attempt was to make the solar tracker with the help of DC motor and gear

train 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 to

simple belt and pulley arrangement also the min.rpm. available with DC motor will make the

gear size very large and to make big size gear is not feasible. Another problem encountered

with 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 the

additional part required are driving circuit and microcontroller circumventing the cost of it

this system is more sophisticated and less complex also easy to assemble

3. Evolution of Solar TrackerSince the sun moves across the sky throughout the day, in order to receive the best angle of

exposure to sunlight for collection energy. A tracking mechanism is often incorporated into

the 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 the

sun across the sky ensuring that the maximum amount of sunlight strikes the panels

throughout the day. When compare to the price of the PV solar panels, the cost of a solar

tracker is relatively low.

Most photovoltaic (PV) solar panels are fitted in a fixed location- for example on the sloping

roof of a house, or on framework fixed to the ground. Since the sun moves across the sky

though 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 facing

South in the Northern Hemisphere, or North in the Southern Hemisphere. Therefore morning

and evening sunlight hits the panels at an acute angle reducing the total amount of electricity

which can be generated each day.

4. System Design

At the beginning of the project, the student and faculty advisor agreed to the following design

requirements:

_ Must track the sun during daylight hours

o 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 autonomous

o The system must operate on, and charge its own battery supply

_ Semi-permanent installation on the flat roof of a building

o A base must be designed to allow installation without fasteners onto a flat section of roof

_ Weather resistant

o This system will be designed to be fully functional outdoors and resist any wind and

weather complications.

_ Remote instrumentation to monitor status

o 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 to

make decisions that would ultimately affect the final design, based on both technical as well

as financial constraints.

_ The solar panel that will convert the radiation of the sun into electricity

o The solar panel in direct sunlight is capable of sourcing 23V under open circuit

conditions, and approximately 0.75A under short circuit conditions. The solar panel

used in this project was already available and therefore did not cost any money

towards the project.

_ 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 enough

and heavy enough to provide a solid mounting point that will prevent the system from being

damaged by strong winds.

_ A weather-resistant housing to protect the electronics

o The final control box had two parts (bottom and top). The interface between the two

included a gasketed design for water-resistance.

_ A motor to move the solar panel as the sun traverses through the sky

o The intent of the project was to automatically rotate the solar panel to orient the panel

perpendicular 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 a

transformer were employed to convert the dc from the batteries/solar panel to a 30

volt modified sine wave ac power source.

_ Electronics to sense the sun’s position, and determine whether the solar panel needs to

move

o The approach employed to orient the panel with the sun was to find the point that

maximized the amount of power being converted by the panel. Current was measured

through a fixed resistance to determine the power consumed.

o An 8051 microcontroller would be the brains of the operation, sensing which position

of the panel yielded maximum power, and sending signals to the antenna motor to

move the solar panel accordingly.

_ A set of two 6V lead-acid batteries, connected in series, that will be charged up during the

day by the solar panel

o The lead-acid batteries were already available and therefore did not cost any money

towards the project.

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 system

repositions 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 rundown

while

looking 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 24

hour 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 initialized

at dawn.

_ The rotor’s base must be initially positioned with the back of the rotor facing north. The

system will not operate correctly otherwise.

5. Solar Tracker

Solar Tracker is basically a device onto which solar panels are fitted which tracks the motion

of the sun across the sky ensuring that the maximum amount of sunlight strikes the panels

throughout the day. After finding the sunlight, the tracker will try to navigate through the

path ensuring the best sunlight is detected.

The design of the Solar Tracker requires many components. The design and construction of it

could be divided into six main parts, each with their main function. They are:

1. Methods of Tracker

2. Methods of Drives

3. Sensor and Sensor Controller

4. Motor and Motor Controller

5. Tracker Solving Algorithm

6. Data Acquisition/Interface Card

The six main parts would need to work together harmoniously to achieve a smooth run for the

Solar Tracker. I shall explore their functions individually in the next section. ar tracker and

less solar panels .

.

http://www.google.co.in/imgres?q=comparison+of+solar+tracking+system+and+simple+solar+system&hl=en&biw=1280&bih=933&tbm=isch&tbnid=TSPwtEuFHtvpyM:&imgrefurl=http://www.ictinternational.com.au/middleton.htm&docid=TM9ZSfl3S0WmtM&imgurl=http://www.ictinternational.com.au/meteorology/solar/images/pst01-2.jpg&w=500&h=361&ei=pGl1T_mEDYKsrAenyKCPDQ&zoom=1

6. TYPES OF SOLAR TRCKER.

Single axis solar trackers

Single axis solar trackers can either have a horizontal or a vertical axle. The horizontal type is

used in tropical regions where the sun gets very high at noon, but the days are short. The

vertical type is used in high latitudes where the sun does not get very high, but summer days

can be very long. a Solar Tracker using horizontal axle. The single axis tracking system is the

simplest solution and the most common one used.

Tracker using horizontal axle

Double axis solar trackers

Double axis solar trackers have both a horizontal and a vertical axle and so can track the

Sun's apparent motion exactly anywhere in the World. Figure 4 shows a Solar Tracker using

horizontal 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 of

the sun across the sky By tracking the sun, the efficiency of the solar panels can be increased

by 30-40%.The dual axis tracking system is also used for concentrating a solar reflector

toward the concentrator on heliostat systems.

Tracker using both horizontal and vertical axle

ACCORDING TO METHOD OF DRIVE

1. Active Trackers

Active Trackers use motors and gear trains to direct the tracker as commanded by a

controller responding to the solar direction. Light-sensing trackers typically have two photo

sensors, such as photodiodes, configured differentially so that they output a null when

receiving the same light flux. Mechanically, they should be unidirectional (i.e. flat) and are

aimed 90 degrees apart. This will cause the steepest part of their cosine transfer functions to

balance 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 one

side or the other (by solar heat creating gas pressure) to cause the tracker to move in response

to an imbalance.

3. Chronological Tracker

Chronological Tracker counteracts the earth's rotation by turning at an equal rate as

the earth, but in the opposite direction. Actually the rates aren't quite equal, because as the

earth goes around the sun, the position of the sun changes with respect to the earth by 360°

every year or 365.24 days.

7. SUN’S APPARENT MOTION

During the day the sun appears to move across the sky from left to right and up and down

above the horizon from sunrise to noon to sunset. Figure shows the schematic above of the

Sun's 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 possible

in order not to lose market shares on the global energy marketplace. There are two main ways

to make the solar cells more efficient, one is to develop the solar cell material and make the

panels even more efficient and another way is to optimize the output by installing the solar

panels on a tracking base that follows the sun.

The end-user will prefer the tracking solution rather than a fixed ground system to increase

their earnings because:

The efficiency increases by 30-40%

The space requirement for a solar park is reduced, and they keep the same output

8. Description of parts used

Technology of Solar Panel

Solar panels are devices that convert light into electricity. They are called solar after the

sun or "Sol" because the sun is the most powerful source of the light available for use. They

are sometimes called photovoltaic which means "light-electricity". Solar cells or PV cells rely

on the photovoltaic effect to absorb the energy of the sun and cause current to flow between

two oppositely charge layers.

A solar panel is a collection of solar cells. Although each solar cell provides a relatively

small amount of power, many solar cells spread over a large area can provide enough power

to 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 physicist

Antoine-Cesar Becquerel. He observed the photovoltaic effect while experimenting with a

solid electrode in an electrolyte solution.

According to Encyclopedia Britannica the first genuine for solar panel was built around

1883 by Charles Fritts. He used junctions formed by coating selenium (a semiconductor) with

an extremely thin layer of gold.

Crystalline silicon and gallium arsenide are typical choices of materials for solar

panels. Gallium arsenide crystals are grown especially for photovoltaic use, but silicon

crystals are available in less-expensive standard ingots, which are produced mainly for

consumption in the microelectronics industry.

Norway’s Renewable Energy Corporation (REC) has confirmed that it will build a

solar manufacturing plant in Singapore by 2010 - the largest in the world. This plant will be

able 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 a

whole produced products that could generate just 2 GW in total.

Bearing.

A bearing is a device to allow constrained relative motion between two parts typically

rotation or linear movement. Bearings may be classified broadly according to the motion they

allow and according to their principle of operation as well as by the direction applied loads

they can handle.

Why use this bearing?

Because of rolling contact , lower friction than any other type.

Ensures smooth operation.

Ease of operation.

Low cost.

Pulley

A pulley is mechanism composed of a wheel with a grove between two flanges

Around 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 a

mechanical 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 is

negligible.

Smooth drive.

Easy install and remove.

Easy to manufacture on small basis

Power Supply

The power supply is provided by 1 pack of eight numbers of 1.2V, 1600mAH NiMH

rechargeable batteries. The total power supply to the stepper motor to operate is 9.6V which

is higher than the 5V for the EMANT300 digital output. Figure 24 shows a pack of eight

numbers of 1.2V, 1600mAH NiMH rechargeable batteries.

9. d escription of electrical parts

Motors.

Motors are use to drive the Solar Tracker to the best angle of exposure of light. For this

section, we shall look at some of the motor types available on the market.

1. Stepper Motors

Stepper motor has relatively limited power which means that wheelspin will not be a

problem. It is not fast but it will work. The driver chips are operated by two signals. One

signal determines the direction of rotation, plus for forward and minus for backwards. The

other moves the stepper by one step each time it goes from minus to plus

Stepper 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 motor

would just stop and not move. They can also produce precise motor rotation if the correct

motor driver firmware signals are obtained.

2. DC Motors

DC motors are cheaper to buy, and simple to drive but they need feed-back sensors to allow

control of the speed. It is necessary to detect the rotation of the wheels, usually by means of

sensors better controlled by pulling the motor supply that uses less battery power than the

analogue/resistor methods. Low-inertia, efficient servo-motors bring advantages of fast

response and efficiency, but add cost .

The advantages of the DC motor are the torque and their speed is easier to control. The

drawbacks of DC motors are that they consumed huge amounts of power. They would

consumed the battery power in no time and power saving techniques must be employed to

ensure the mouse do not stop halfway while navigating. They are also prone to dust and

harder to maintain.

DC MOTOR

3. Servo Motors

Servos contain a small DC motor, a gearbox and some control circuitry, and feed on 5

volts at about 100mA maximum, and about 10-20mA when idle. They have a three-wire

connector, one common wire (0 volt, usually black), one +5v wire (usually red), and one

signal wire. In normal use they are controlled by pulses of about 1 to 2 milli-seconds at a

repetition rate of about 50 per second.

A short pulse makes the servo drive to one end of the travel, a long pulse makes it

drive to the other end, and a medium one puts it somewhere proportionally between. Some

servos have gear components that allow them to rotate continuously. This method needs the

servo to have a feedback potentiometer used by internal circuits to measure the position of

the output shaft. If this is disconnected and the wires taken to an external pre-set

potentiometer, the servo will drive continuously in one direction if fed with short pulses and

vice-versa.

If there are no pulses, the servo stops. It is uses to drive the Solar Tracker Eastward

and Westward. The pulses are at normal TTL levels. The speed though, is not greatly affected

by the pulse repetition rate, as long as it is above about 30 per second. These pulses can easily

be provided by an output port of just about any computer, for instance the data or control

lines of a printer port or a serial port, or a simple addressed latch added to the memory

circuits. A possible configuration is the tricycle described above, with one driving and

steering-wheel at the front and two idler wheels at the rear.

Using a Radio Controlled (RC) servo for steering is a good method, because the

position 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 servo

is used as a drive motor, wheel motion sensors are needed on at least one wheel as in any DC

motor

Sensors

A sensor is a device that measures a physical quantity and converts it into a signal which can

be read by an observer or by an instrument.

1. Light Dependent Resistor

Light Dependent Resistor (LDR) is made of a high-resistance semiconductor. It can

also be referred to as a photoconductor. If light falling on the device is of the high enough

frequency, photons absorbed by the semiconductor give bound electrons enough energy to

jump into the conduction band. The resulting free electron (and its hole partner) conduct

electricity, thereby lowering resistance. Hence, Light Dependent Resistors (LDR) is very

useful 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 sensitive

silicon PIN photodiode in a miniature flat plastic package. A photodiode is designed to be

responsive to optical input. Due to its water clear epoxy the device is sensitive to visible and

infrared radiation.

The large active area combined with a flat case gives a high sensitivity at a wide

viewing angle. Photodiodes can be used in either zero bias or reverse bias. In zero bias, light

falling on the diode causes a voltage to develop across the device, leading to a current in the

forward 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 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 detector by monitoring the current

running through it. Circuits based on this effect are more sensitive to light than ones based on

the photovoltaic effect.

Sensing around the tracker

The sensors work on a system of two photodiodes comparator circuit. the circuit diagram of

East 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 × Vo

= 2400 × 2.5V

= 6000 lux

The human eye is a very poor “instrument” for measuring light intensity, because the pupil

adjusts constantly in response to the amount of light it receives. To accurately measure the

light 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 they

require only that their coils be driven on and off. The stepping sequence for a four-coil

unipolar steppers is shown on table 4 below.

Stepping sequence for a four‐coil uni polar steppers

The motor’s speed depends on how fast the controller runs through the step sequence.

The stepper motor I have used is the PF443-03A from Mycom. It requires a supply voltage of

12V 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 stepper

motor coil. Besides, the Mycom PF443 stepper motor operates from a 12V supply which is

higher than the 5V allowed for the EMANT300 digital output. Therefore, one simple solution

is to add the ULN2003. Figure 22 shows the pin configuration of ULN2003. It is a high

voltage, high current darlington driver comprising seven NPN darlington pairs. All feature

integral clamp diodes for switching inductive loads. The ULN2003 has a maximum

sustaining output voltage of 50V and maximum output current of 0.5A per channel which

easily exceeds the requirements of the

10. DESIGN CONSIDERATION.

Supporting table:

Two layer design, to avoid following:

Shaft bending

Shaft vibration

Rigid 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 height

To allow rotation solar panel without interference

Diameter selected:

Based on weight of solar plate

Shaft material

Hollow shaft to reduce of shaft

Bearing:

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.

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

11. Specification of parts

Solar panel

Module type: PE 1210

Rated power :pmax: 6 watts

V avg: 12 volt

Current I avg: 0.6 amps

Voc: 17 volt

Current (max)sc: 0.7ampr

Size: 30*45(cm)

Dc motor:

Type:

Volt:

Current:

Torque:

Step per evolution:

Step angle:

Shaft diameter:

Bearing:

Type:

Inner diameter:

Out diameter:

Material:

No:

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:

Stand:

Type:

Length:

Width:

Plate thickness:

Leg cross-section:

Gap between plate:

Material:

Bolt:

Diameter:

Length:

No:

Material:

12. ASSEMBLY TECHNIQUE

First 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 avoid

slippage.

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.

13. Working principle

Sun is the source of energy. This energy is in form of electromagnetic wave strikes on

to 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 series

Out of three batteries two battery are connected across the stepper motor through controller

circuit.

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 pulley

to provided on main shaft through belt.

Structure of Solar Tracker

The structure of my Solar Tracker is based on the horizontal-axle Solar Tracker method. , fig.

show the overview, top view and side view respectively where all the components are place.

14.Programming Language

for the Solar Tracker

The program which I have chosen to run this Solar Tracker Algorithm is LabVIEW. It

is a programming language from National Instruments, also referred to a VI (Virtual

Instrument), consists of two windows: the Front Panel and the Block Diagram. It is a

graphical language in which the program is drawn rather than written. There is no text-based

code like in Basic or C. The program is presented as a diagram with data flow determining

the sequence of the program

Lab VIEW uses its own National Instruments Data Socket technology to share live

data with other VI on the Web. The Lab VIEW Web Server is use to create HTML

documents, publish front panel images on the Web, and embed VI in a Web page. It also

controls browser access to the published front panels and configures which VIs are visible on

the Web. Protocols that are use include the HTTP and TCP/IP and are dependable on the

application. A plug-in package called the Lab VIEW Run-Time Engine is needed to access

the Lab VIEW applications .Other programming languages like the Java, Pearl,

Microprocessor and C++ could also be used to write the software.

Solar Tracker – Solving Algorithm

The main objective of the Solar Tracker Algorithm is to quickly determine to the best angle

of exposure of light from the sun. A pair of sensors is used to point the East and West of the

location of the light. Figure shows a flow chart of Solar Tracker Algorithm.

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;

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();

P0=ox66;

Delay l();

1=1+4;

}

1=o;

ROTATION ENDS

Delay();

While(1<=100)

ROTATION STARTS

{

P0=0xaa;

Delay();

MINUTES

P0=0x99;

Delay();

P0=0x55;

Delay();

P0=0x66;

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)

{

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++);

}

15. Analysis and Perception

To simulate interest in young professionals and students in solar, solar competitions

are held worldwide annually. Of particular interest would be the Solar Tracker competition

that saw professionals and students taking part. This competition sees solar panels are fitted

which tracks the motion of the sun across the sky ensuring that the maximum amount of

sunlight 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 of

the methods had their advantages and disadvantages. Of particular interest would be the

single-axis and active tracker method as it is symmetric placements and turnings of the

motor.

The eyes of the Solar Tracker are taken care by the photodiodes. The photodiodes are

important 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 not

hold up too much space

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 System

Explanation of Each Component in Block Diagram

Microcontroller: - This is the heart of the circuit which performs all commanding and

controlling operations. Microcontroller now days are becoming more popular because of

several advantages over microprocessor. As it reduces the requirement of additional

interfacing IC those are needed in microprocessor, the data which has to be read and

controlled is directly fed to microcontroller and the software is designed in accordance with

the 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 the

direction of maximum intensity of light. The difference between the outputs of the sensors is

given to the microcontroller unit.

Oscillators:-Two oscillators would be used for generating square waves. The sensors are

connected to these two oscillators which generate 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.

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 microcontroller

is 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 the

stepper motor. This circuit has transistors in darlington pair with free-wheeling diodes.

89c51 microcontroller hardware

89C52:- Here microcontroller IC 89C52 used is a 40 pin IC consists of four ports which are

used as an input and output port. This is the heart of the circuit which performs all

commanding and controlling operations. Microcontroller now days are becoming more

popular because of several advantages over microprocessor. As it reduces the requirement of

additional interfacing IC those are needed in microprocessor, the data which has to be read

and controlled is directly fed to microcontroller and the software is designed in accordance

with 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 be

using two LDR sensors in two different directions to sense the direction of maximum

intensity of light. The difference between the outputs of the sensors is given to the

microcontroller unit.

555:- For generating square pulses ICs 555 are used as oscillators. Two oscillators would be

used for generating square waves. The sensors are connected to these two oscillators which

generate 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 first

power supply is 5v regulated power supply it is used to supply power to microcontroller and

sensing 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 1N4110

diodes are being used in order to increase the current gain that is required to drive the stepper

motor.

DATA

1. POWER OUT PUT OF SOLAR PANEL AT DIFFERENT ANGLE OF INCIDENCE WITH VERTICAL AXIS

DATA

SR NO ANGLE VOLTAGE CURRENT POWER1 02 103 204 305 456 607 708 809 90

2. DATA OF AMPERE VOLTAGE FROM SOLAR PANEL FOR THE WHOLE DAY AT A GIVEN TIME INTERVAL WITHOUT SOLAR TRACKER

SR NO TIME(am/pm) VOLTAGE(v) CURRENT(amps) POWER(watt)

12345678910111213141516171819202122232425AVERAGE

3. DATA OF AMPERE VOLTAGE FROM SOLAR PANEL FOR THE WHOLE DAY AT A GIVEN TIME INTERVAL WITH SOLAR TRACKER

SR NO TIME(am/pm) VOLTAGE(v) CURRENT(amps) POWER(watt)

12345678910111213141516171819202122232425AVERAGE

Comparision of solar tracking system to simple solar system

with graph

16. Conclusion

This project had been a great learning experience. Apart from engineering skills, I

also learnt time management skills, project management skills and experience in starting a

project which I had no idea about.

I believe that I have done well with all the constraints. I am a part time student from

different working backgrounds and experiences. Although lacking in the expertise of solar

tracker, I’m still manage to complete the individual parts.

17. REFERANCE

WWW.GOOGLE.COM WIKIPEDIA WWW.MENDELEY.COM

WWW.8089PROJECT.NET WWW.ENGINEERING PROJECT.COM WWW.SOLAR-PHOTOVOLTIC.INFO