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 Guide
Asst. Prof. KALPESH PARMAR
(M. E. Dept.)
Submitted to
Noble Group of Institutions-Junagadh
Mechanical Engineering Department
Year 2011-2012
2.
3. 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
4. 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.
=
5. 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.
6. 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”.
7. 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
8. 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 TECHNIQUE
13. 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
9. 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.
10. 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
11. 3. Evolution of Solar Tracker
Since 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.
12. 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.
13. _ 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.
14. 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.
15. 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 .
.
16.
17. 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
18. 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
19. 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.
20. 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
21. 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.
22. 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.
23. 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
24. 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.
25. 9. description 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.
26.
27. 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
28. 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
29. 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.
30. 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 × V
o
= 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.
31. 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
32. 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:
33. 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.
34. 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
35. 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:
38. 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.
39. 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.
40. 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.
41. 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.
42. 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.
43. 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;
48. 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
49. 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
50. 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.
52. 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.
53. DATA
1. POWER OUT PUT OF SOLAR PANEL AT DIFFERENT ANGLE OF
INCIDENCE WITH VERTICAL AXIS
DATA
SR NO ANGLE VOLTAGE CURRENT POWER
1 0
2 10
3 20
4 30
5 45
6 60
7 70
8 80
9 90
54. 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)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
AVERAGE
55. 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)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
AVERAGE
59. 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.
