Solar tracking system final report GTU

13,488 views 34 slides Apr 24, 2018
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About This Presentation

- The objective of this project is to make a smart solar panel which is follow the sun light. Solar panel converts sun light into electricity. It is eco-friendly and low-cost energy. But the solar panel is unable to move in front of the light source, hence solar panel not produces electricity of its...


Slide Content

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GUJRAT TECHNOLOGICAL UNIVERSITY
Chandkheda,Ahmedabad
Affilated




Silver Oak college of Engineering & Technology
A Report on
SOLAR TRACKING SYSTEM
Under subject of
DESIGN ENGINEERING - 1B
B.E.-II , SEMESTER-IV,
MECHANICAL ENGINEERING
SUBMITTED BY:-
Sr no. Name En no.
1. Vegda Dilip R. 150773119070
2. Patel Dhrumil 150773119038
3. Makwana Akash 150773119023
4. Parikh ajay 150773119031
Prof. Mit K. Shah
(Head Of Department)
Mr. Vatsal Chaudhari
(Faculty Guide)

Acedemic Year
(2015-2016)

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SILVER OAK COLLGEG OF ENGINEERING AND TECHNOLOGY
Department of Mechanical Engineering
2016– 2017
CERTIFICATE
Date:
This is to certify that the Design Engineering – 1B. Work entitled “DEPLOY
ABLE CRADLE”, carried out by the group of students mentioned below under my
guidance is approved for the Degree of Bachelor of Engineering in Mechanical En
gineering (Semester - IV) of Gujarat Technological University, Ahmedabad during
the academic year 2016-17.
List of Students:-
1. Vegda Dilip R. 150773119070
2. Patel Dhrumil 150773119038
3. Makwana Akash 150773119023
4. Parikh ajay 150773119031

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ABSTRACT
The objective of this project is to make a smart solar panel which is follow the sun light. Solar
panel converts sun light into electricity. It is eco-friendly and low-cost energy. But the solar
panel is unable to move in front of the light source, hence solar panel not produces electricity of
its full capacity. Solar panel is unable to move, it is fixed at one position. If we want full energy
output from solar panel thenwe need to move manualy solar panel in front of the sun light
In this project,
This report aims to let the reader understand the project work which I have done. A brief
introduction to Solar Panel and Solar Tracker is explained in the Literature Research section.
Basically the Solar Tracker is divided into two main categories, hardware and software. It is
further subdivided into six main functionalities: Method of Tracker Mount, Drives, Sensors,
Motors, Data Acquisition/Interface Card and Power Supply of the Solar Tracker is also explained
and explored. The reader would then be brief with some analysis and perceptions of the
information.
Next, the overview of the hardware and software of the Solar Tracker would be introduced. A
detailed insight and main focus of this report of the sensor system and circuitry is explained

Finally, the results, some discussions, conclusions and reflections of the project are discussed.
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. After that he saw a voltage developed when light fell upon
the electrode.

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AKNOWLEDGEMENT
In these years of degree engineering our faculty Mr. has guided us to achieve a goal and made us
capable to complete our Mini Project work successfully. So we would like to take this chance to
thank our Project guide, Lab assistants and college with whose support and skillful guidance has
made us such as that we would be proud of wherever we go and always be confident in achieving
our goals. Firstly we would like to give our sincere regards to all our Faculty Members of
Mechanical Engineering Department for giving their excellent guidance and who gave us the
confidence that we can complete this project successfully. All Faculties of mechanical branch
have shared their valuable ideas and industrial knowledge about for this project and that’s why
we are also thanking them for their help. We are thankful to our project guide Mr. , We are
thankful that we got the chance to work under his guidelines and our sincere and heartily regards
to them. We would also like to give vote of thanks to Mr. Mit k Shah who has given us
permission to carry out this Project work and for providing with the material which initiated our
Project work. Finally last but not the least we are very much thankful to our Team Members,
Friends and our Principal Prof. Saurin Shah for their kind support and co-ordination during the
entire span of Education till now in silver oak college of Engineering and Technology.





o

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INDEX PAGE NO.



1. INTRODUCTION 7
2. WHY WE SELECT THIS PROJECT? 8
3. SOLAR DECRIPTION 9
4. PHOTOVOLTAICS 11
4.1. SOLAR CELL 11
4.2 TYPES OF SOLAR PANELS: 12
5. GEAR 14
6. MOTOR 16
7. TYPES OF TRACKERS 17
7.1 TRACKER MOUNT TYPES 17
7.2 DRIVE TYPES: 18
8. HARDWARE DESCRIPTION 19
8.1 BASIC BLOCK DIAGRAM: 19
8.2 POWER SUPPLY: 19
8.3 AT89C51 MICROCONTROLLER 20
8.4 PART LIST OF SOLAR TRACKING SYSTEM 21
8.5 PART LIST FOR SENSOR CIRCUIT 22
8.6 KEYPAD 27
8.8 L293D DRIVER 27
9. PROJECT IMPLEMENTATION 28
9.1 HARD WARE IMP8LEMENTATION 28
9.1.1 SCHEMATIC: 28
9.1.2 INTERFACING LCD WITH MICRO CONTROLLER: 28
9.1.3 INTERFACING L293D DRIVER AND GEAR MOTOR WITH MICRO
CONTROLLER: 29
9.1.4 INTERFACING DS1307 WITH MICROCONTROLLER: 30
9.3 LIGHT INTENSITY SENSOR 31
10. PRONS AND CONS 33
11. CONCLUSION: 34

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Introduction
Name of the team :-mechanical squad
Team Member’s Introduction
Vegda dilip R.
He was the main designer of the project as well as he took very active part
in creating our product. He gave his drawing expertise to the project in a way that the
project reached a different level of creativity.
E-mail :- [email protected]
Contact No:- 8866037043

Patel dhrumil S.
He is the member of our team who has been working very hard to
complete the project report with dedication. He helped as much as possible in the
ideation and product development canvas. He has been helping hand in preparing
canvas work.


Contact No:- 7405132068
Makwana akash d.

He is the member of our group who has helped in doing all work of the
project like making of canvas, report and other work very efficiently.
E-mail :- [email protected]

Contact No:- 8866101561

Parikh ajay H.

With his fantastic skills of creations of ideas he supported the group in
selecting the topic as well as to explore more about this topic.

Contact No.8306396544

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1.INTRODUCTION
A solar tracker is a device for orienting a Photovoltaic array solar photovoltaic panel or
concentrating solar reflector or lens toward the sun. The sun's position in the sky varies
both with the seasons (elevation) and time of day as the sun moves across the sky.
Solar powered equipment works best when pointed at or near the sun, so a solar
tracker can increase the effectiveness of such equipment over any fixed position, at the
cost of additional system complexity. There are many types of solar trackers, of varying
costs, sophistication, and performance. One well-known type of solar tracker is the
heliostat, a movable mirror that reflects the moving sun to a fixed location, but many
other approaches are used as well.

Non-concentrating applications require less accuracy, and many work without any
tracking at all. However, tracking can substantially improve both the amount of total
power produced by a system and that produced during critical system demand periods
(typically late afternoon in hot climates). The use of trackers in non-concentrating
applications is usually an engineering decision based on economics. Compared to
photo voltaic, trackers can be inexpensive. This makes theme specially effective for
photovoltaic systems using high-efficiency (and thus expensive) panels.

Extracting usable electricity from the sun was made possible by the discovery of the
photoelectric mechanism and subsequent development of the solar cell – a semi
conductive material that converts visible light into a direct current. By using solar arrays,
a series of solar cells electrically connected, a DC voltage is generated which can be
physically used on a load. Solar arrays or panels are being used increasingly as
efficiencies reach higher levels, and are especially popular in remote areas where
placement of electricity lines is not economically viable.

The process of sensing and following the position of the sun is known as Solar
Tracking. It was resolved that real-time tracking would be necessary to follow the sun
effectively, so that no external data would be required in operation.

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2. WHY WE SELECT THIS PROJECT?

 The most energy is absorbed when a surface’s face is perpendicular to the sun.

 Stationary mounted PV panels are only perpendicular to the sun once a day.

 Improved performance from each panels means fewer panels are needed.

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3.SOLAR DECRIPTION



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. Figure 3 shows a Solar Tracker using
horizontal axle. The single axis tracking system is the simplest solution and the most
common one used.



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.
(4)
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.
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.

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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.
Power Supply
The power supply of the solar tracker is also a consideration when designing.
They would have to supply power to the interface card, the motors and the sensors.
Although there are other electric power sources available, batteries is the best source
for the Solar Tracker. To ensure the proper operation of all circuitry and their
components, power must be provided through a voltage regulation scheme.The table
below compares the different type of batteries available.

The light detected by the Eastward-facing sensor is at a lower intensity to that
detected by the Westward-facing sensor. Hence, the sensor must be turned westwards
(by the motor controlled by the solar tracker circuit) until the levels of light detected by
both the East and the West sensors are equal. At the point of the solar panel will be
directly facing the light and generated electricity optimally.
Obviously real world solar trackers are not so simple. A solar tracker must be able to
reset itself at sunset so it is ready for sunrise, it must cope with heavy cloud, and it must
work reliably 365 days a year. In addition a mount for the solar panel must be
constructed

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4.PHOTOVOLTAICS

Photovoltaic(PV) is a technology that converts light directly into electricity.Photovoltaicis
also the field of study relating to this technology and there are many research institutes
devoted to work on photovoltaic. Due to the growing need for solar energy, the
manufacture of solar cells and solar photovoltaic array has expanded dramatically since
2002.making it the world’s fastest-growing energy technology.

4.1. SOLAR CELL
Photovoltaic energy is the conversion of sunlight into electricity. A photovoltaic cell,
commonly called a solar cell or PV, is the technology used to convert solar energy
directly into electrical power. A photovoltaic cell is a non-mechanical device usually
made from silicon alloy.

FIG:4.1 Solar Cell

The photovoltaic cell is the basic building block of a photovoltaic system. Individual cells
can vary in size from about 0.5 inches to about 4 inches across. However, one cell only
produces 1 or 2 watts, which isn't enough power for most applications.

The performance of a photovoltaic array is dependent upon the sunlight .Climatic
conditions (eg., clouds, fog) have a significant effect on the amount of solar energy
received by a photovoltaic array and, in turn, its performance. Most current technology
photovoltaic modules are about 10% efficient in converting solar radiation. Further
research is being conducted to raise this efficiency to 20%.

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4.2 TYPES OF SOLAR PANELS:
There are 4 types of Solar Panels and I have them broken down for you below.

MONO CRYSTALLINE:
Mono crystalline solar panels are made from a large crystal of silicon. These type of
solar panels are the most efficient as in absorbing sunlight and converting it into
electricity, however they are the most expensive. They do somewhat better in lower light
conditions then the other types of solar panels.


POLYCRYSTALLINE:
Polycrystalline solar panels are the most common type of solar panels on the market
today. They look a lot like shattered glass. They are slightly less efficient then the
monocrystalline solar panels and less expensive to produce. Instead of one large
crystal, this type of solar panel consists of multiple amounts of smaller silicon crystal.

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CAST POLYSILICON:
In this process, molten silicon is cast in a large block which, when cooled, can be cut
into thin wafers to be used in photovoltaic cells. These cells are then assembled in a
panel. Conducting metal strips are then laid over the cells, connecting them to each
other and forming a continuous electrical current throughout the panel.

STRING RIBBON SILICON:
String ribbon uses a variation of the polycrystalline production process, using the same
molten silicon but slowly drawing a thin strip of crystalline silicon out of the molten form.
These strips of photovoltaic material are then assembled in a panel with the same metal
conductor strips attaching each strip to the electrical current.

AMORPHOUS SOLAR PANELS



Amorphous solar panels consist of a thin-like film made from molten silicon that is
spread directly across large plates of stainless steel or similar material. These types of
solar panels have lower efficiency then the other two types of solar panels, and the
cheapest to produce. One advantage of amorphous solar panels over the other two is
that they are shadow protected. That means that the solar panel continues to charge
while part of the solar panel cells are in a shadow. These work great on boats and other
types of transportation.

SOLAR PANEL EFFICIENCY DETAILS:
Mono crystalline- 18%
Polycrystalline- 15%
Amorphous (thin-film)- 10%

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5. GEAR



Aworm driveis a gear arrangementin which aworm(which is a gear in the form of a
screw) meshes with aworm gear(which is similar in appearance to a spur gear). The two
elementsare also called theworm screwandworm wheel. The terminology is often
confused by imprecise use of the termworm gearto refer to the worm, the worm gear, or
the worm drive as a unit.

A gearboxdesigned using a worm and worm-wheel will be considerably smaller than
one made from plain spur gearsand has its drive axes at 90° to each other. With asingle
startworm, for each 360° turn of the worm, the worm-gear advances only one tooth of
the gear. Therefore, regardless of the worm's size (sensible engineering limits
notwithstanding), the gear ratio is the"size of the worm gear - to - 1". Given a single start
worm, a 20 tooth worm gear will reduce the speed by the ratio of 20:1. With spur gears,

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a gear of 12 teeth (the smallest size permissible, if designed to good engineering
practices) would have to be matched with a 240 tooth gear to achieve the same ratio of
20:1. Therefore, if the diametrical pitch (DP) of each gear was the same, then, in terms
of the physical size of the 240 tooth gear to that of the 20 tooth gear, the worm
arrangement is considerably smaller in volume.

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6. MOTOR

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2 At mega microcontrollers
Amicrocontroller(sometimes abbreviatedµC,uCorMCU) is a small computeron a single
integrated circuitcontaining a processor core, memory, and programmable
input/outputperipherals. Program memory in the form of Ferroelectric RAM, NOR flashor
OTP ROMis also often included on chip, as well as a typically small amount of RAM.
Microcontrollers are designed for embedded applications, in contrast to the
microprocessorsused in personal computersor other general purpose applications.
Microcontrollers are used in automatically controlled products and devices, such as
automobile engine control systems, implantable medical devices, remote controls, office
machines, appliances, power tools, toys and other embedded systems. By reducing the
size and cost compared to a design that uses a separate microprocessor, memory, and
input/output devices, microcontrollers make it economical to digitally control even more
devices and processes. Mixed signalmicrocontrollers are common, integrating analog
components needed to control non-digital electronic systems.

7. TYPES OF TRACKERS
7.1TRACKER MOUNT TYPES
Solar trackers may be active or passive and may be single axis or dual axis .Thereare
two types of dual axis trackers, polar and altitude-azimuth.

Single axis trackers:
Horizontal axis:
Several manufacturers can deliver single axis horizontal trackers which may be oriented
by either passive or active mechanisms, depending upon manufacturer. In these, a long
horizontal tube is supported on bearings mounted upon pylons or frames. The axis of
the tube is on a North-South line. Panels are mounted upon the tube, and the tube will
rotate on its axis to track the apparent motion of the sun through the day. These devices
are less effective at higher latitudes. The principal advantage is the inherent robustness
of the supporting structure and the simplicity of the mechanism.

Vertical axis:
A single axis tracker may be constructed that pivots only about a vertical axle, with the
panels either vertical, at a fixed, adjustable, or tracked elevation angle. Such trackers
with fixed or (seasonably) adjustable angles are suitable for high latitudes, where the
apparent solar path is not especially high, but which leads to long days in Summer,

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Two-axis mount:
Altitude-azimuth
A type of mounting that supports the weight of the solar tracker and allows it to move in
two directions to locate a specific target. One axis of support is horizontal (called the
altitude) and allows the telescope to move up and down. The other axis is vertical
(called the azimuth) and allows the telescope to swing in a circle parallel to the ground.
Restricted to active trackers, this mount is also becoming popular as a large telescope
mount owing to its structural simplicity and compact dimensions.


Multi-mirror reflective unit:
A multiple mirror reflective system combined with a central power tower is employed at
the Sierra Sun Tower, located in Lancaster, California. This generation plant operated
by eSolar is scheduled to begin operations on August 5, 2009. This system, which uses
multiple heliostats in a north-south alignment, uses pre-fabricated parts and
construction as a way of decreasing startup and operating costs.


7.2 DRIVE TYPES:
Active tracker
Active trackers use motors and gear trains to direct the tracker as commanded by a
controller responding to the solar direction.Active two-axis trackers are also used to
orient heliostats - movable mirrors that reflect sunlight toward the absorber of a
centralpowerstation. As each mirror in a large field will have an individual orientation
these are controlled programmatically through a central computer system, which also
allows the system to be shut down when necessary.

Passive tracker
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. As this is a non-precision orientation it is unsuitable for
certain types of concentrating photovoltaic collectors but works fine for common PV
panel types. These will have viscous dampers to prevent excessive motion in response
to wind gusts. Shader/reflectors are used to reflect early morning sunlight to "wake up"
the panel and tilt it toward the sun, which can take nearly an hour. The time to do this
can be greatly reduced by adding a self-releasing tiedown that positions the panel
slightly past the zenith (so that the fluid does not have to overcome gravity) and using
the tiedown in the evening. (A slack-pulling spring will prevent release in windy
overnight conditions.)

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8.HARDWARE DESCRIPTION
8.1 BASIC BLOCK DIAGRAM:

8.2 POWER SUPPLY:
In this project power supplies with +5V & -5V option normally +5V is enough for total
circuit. Another supply is used in case of OP amp circuit .Transformer primary side has
230/50HZ AC voltage whereas at thesecondary winding the voltage is step downed to
12/50hz and this voltage is rectified using two full wave rectifiers .The rectified output is
given to a filter circuit to filter the unwanted ac in the signal After that the output is again
applied to a regulator LM7805(to provide +5v) regulator. WhereasLM7805 is for
providing 5V regulation.

Fig: 8.2 Block Diagram Of Power Supply

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A step down transformer is used to convert 230V 50HZ line voltage 12V ac input to the
supply pin of the circuit. The ac voltage is converted to pulsated dc using a center
tapped full wave rectifier. Any ripples if present are eliminated using a capacitive filter at
the output of the full wave rectifier. The capacitive filter output is input to LM
7805(voltage regulator), which produces a dc equivalent of ac 5V. This 5V dc acts as
VCC to the micro controller.




Circuit Features:

Brief description of operation: Gives out well regulated +5V output, output current
capability of 1A

Circuit complexity: Very simple and easy to build

Circuit performance: Very stable +5V output voltage, reliable operation Availability of
components: Easy to get, uses only very common basic components

Applications: Part of electronics devices, small laboratory power supply

Power supply voltage: 230V AC

Power supply current: 1A

8.3 AT89C51 MICROCONTROLLER

FEATURES

 8-Kbytes of on-chip Reprogrammable Flash Memory
 128 x 8 RAM
 Memory addressing capability
 Industrial temperature available

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8.4 PART LIST OF SOLAR TRACKING SYSTEM
Main Board Part
RESISTORS :-
R1 - -1KΩ
R2 - -8K2Ω
RN3 - -10KΩ Array
CAPACITORS :-
C1,C2 - -33PF
C3 - -100µF/16V
C4 - -1000µF/25V
C5 - -100KPF
C6 - -10µF/25V
SEMICONDUCTORS : -
B1 - -1A Bridge Rectifier
U1 - -LM7805
U2 - -89C51 MCU
U3 - -L293D
LCD - -16*2 LCD
X1 - -11.0592 Crystal
L1 - -Red Led
MISCELLANOUS :-
SW1 - -ON/OFF Switch
Socket -DC Socket for Supply
Socket and connectors

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8.5PART LIST FOR SENSOR CIRCUIT
RESISTORS :-
R1 - -100Ω
R2,R3,R5 -1KΩ
R4,R6 - -10KΩ
P1 - -20KΩ Preset
LDR - -50KΩ LDR
CAPACITORS :-
C1 - -1000µF/16V
C2 - -10µF/25V
C3 - -10KPF
SEMICONDUCTORS : -
D1 - -1N4007
T1 - -BC557
U1 - -NE555
L1,L2 - -Red,Green Light

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GENERAL DESCRIPTION:

THE MICROCONTROLLER:
A microcontroller is a general purpose device, but that is meant to read data, perform
limited calculations on that data and control its environment based on those
calculations. The prime use of a microcontroller is to control the operation of a machine
using a fixed program that is stored in ROM and that does not change over the lifetime
of the system.
The microcontroller design uses a much more limited set of single and double byte
instructions that are used to move data and code from internal memory to the ALU. The
microcontroller is concerned with getting data from and to its own pins; the architecture
and instruction set are optimized to handle data in bit and byte size.



FIG 8.4.1

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The AT89C51 is a low-power, high-performance CMOS 8-bit microcontroller with 4k
bytes of Flash Programmable and erasable read only memory (EROM). The device is
manufactured using Atmel’s high-density nonvolatile memory technology and is
functionally compatible with the industry-standard 80C51 microcontroller instruction set
and pin out.

PIN CONFIGURATION :

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PIN DESCRIPTION:

VCC GND
Supply voltage Ground

Port 0
Port 0 is an 8-bit open drain bi-directional I/O port. Port 0 can also be configured to be
the multiplexed low order address/data bus during access to external program and data
memory.

Port 1
Port 1 is an 8-bit bi-directional I/O port. The port 1output buffers can sink/source four
TTL inputs.

Port 2
Port 2 is an 8-bit bi-directional I/O port with internal pull-ups. The port 2 output buffers
can sink/source four TTL inputs. When 1s are written to port 2 pins, they are pulled high
by the internal pull-ups can be used as inputs. As inputs, Port 2 pins that are externally
being pulled low will source current because of the internal pull-ups.

Port 3
Port 3 is an 8-bit bi-directional I/O port with internal pull-ups. The port 3 output buffers
can sink/source four TTL inputs. When 1s are written to port 3 pins, they are pulled high
by the internal pull-ups can be used as inputs.

RST
Rest input A on this pin for two machine cycles while the oscillator is running resets the
device .

ALE/PROG:
Address Latch Enable is an output pulse for latching the low byte of the address during
access to external memory. This pin is also the program pulse input (PROG) during
Flash programming.

PSEN
Program Store Enable is the read strobe to external program memory when the
AT89c51 is executing code from external program memory PSEN is activated twice
each machine cycle, except that two PSEN activations are skipped during each access
to external data memory.

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EA /VPP
External Access Enable (EA) must be strapped to GND in order to enable the device to
fetch code from external program memory locations starting at 0000h up to FFFFH.
Note, however, that if lock bit 1 is programmed EA will be internally latched on reset. EA
should be strapped to Vcc for SOLAR.

TRACKING SYSTEM
internal program executions. This pin also receives the 12-volt programming enable
voltage (Vpp) during Flash programming when 12-volt programming is selected.
XTAL1
Input to the inverting oscillator amplifier and input to the internal clock operating circuit.
XTAL 2
Output from the inverting oscillator amplifier.
OPERATING DESCRIPTION
The detail description of the AT89C51 included in this description is: • Memory Map and
Register • Timer/Counters


6.5LCD (LIQUID CRYSTAL DISPLAY)

General Description:
The Liquid Crystal Display (LCD) is a low power device (microwatts). Now a days in
most applications LCDs are using rather using of LED displays because of its
specifications like low power consumption, ability to display numbers and special
characters which are difficult to display with other displaying circuits and easy to
program. An LCD requires an external or internal light source. Temperature range of
LCD is 0ºC to 60ºC and lifetime is an area of concern, because LCDs can chemically
degrade these are manufactured with liquid crystal material (normally organic for LCDs)
that will flow like a liquid but whose molecular structure has some properties normally
associated with solids. .


LCDs are classified as

1. Dynamic-scattering LCDs and
2. Field-effect LCDs

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FIELD EFFECT LCD:
Field-effect LCDs are normally used in such applications where source of energy is a
prime factor (e.g., watches, portable instrumentation etc.).They absorb considerably
less power than the light-scattering type. However, the cost for field-effect units is
typically higher, and their height is limited to 2 inches. On the other hand, light-
scattering units are available up to 8 inches in height. Field-effect LCD is used in the
project for displaying the appropriate information



Fig: 8.5.1 Liquid Crystal Displ

8.6 KEYPAD
Keypads are a part of HMI or Human Machine Interface and play really important role in
a small embedded system where human interaction or human input is needed. Matrix
keypads are well known for their simple architectureand ease of interfacingwith
anymicrocontroller.


8.8 L293D DRIVER
The L293D is a monolithic integrated high voltage, high current four channel driver
designed to accept standard DTL or TTL logic levels and drive inductive loads and
switching power transistor. To simplify use as two bridges is pair of channels is
equipped with an enable input. A separate supply input is provided from the logic,
allowing operational at a low voltage and internal clamp diodes are included . This
device is suitable for use in switching applications at frequencies up to 5 KHz

The L293D is assembled in a 16 lead plastic package which has 4 center pins
connected together and used for head sinking

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Fig 8.8.1 Pin Configuration of L293d
FEATURES:
 600ma. output current capability perchannel
 enable facility
 over temperature protection
 internal clamps diodes.


9.PROJECT IMPLEMENTATION

9.1 HARD WARE IMP8LEMENTATION
9.1.1 SCHEMATIC:
9.1.2 INTERFACING LCD WITH MICRO CONTROLLER:

Fig 9.1 Interfacing Lcd With Microcontroller

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Lcd (Liquid Crystal Display) was connected to microcontroller through pins (D0-D3)
to(p1.4-p1.7) respectively to send the data through microcontroller ,R/W pin was
connected to ground ,RS PIN to P2.0,EN pin to P2.1,and Vcc to supply pin.


9.1.3 INTERFACING L293D DRIVER AND GEAR MOTOR WITH
MICROCONTROLLER:




Fig 7.2 Interfacing L293d Driver With Gear Motor

L293D was connected to micro controller through pins p0.0 andP0.1 .3and4 pins are
connected to D.C BRUSHLESS MOTOR positive and negative pins. 4,5 pins were
shorted and given to 9v supply. 7,11,13,14 left open and remaining pins were
connected to ground.

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9.1.4INTERFACING DS1307 WITH MICROCONTROLLER:





Fig 9.3 Interfacing Ds 1307 With Micro Controller


DS 1307 was connected to the micro controller through pins P3.2, P3.4, P3.3 to the pins 7, 6, 5
respectively. 1, 2pins were connected to 33KHZ crystal oscillator and the remaining pins were
connected to supply of 3.6V.

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9.3 Light Intensity Sensor

To command the PV panel motion, we used two light intensity sensors, executed using
two luminescent diodes of LED type, placed so that the signal they generate is
correlated with the light intensity applied to the PV panel, as in Fig. 5. The two LEDs are
placed normal to the panel surface and are separated by an opaque plate. Thus,
depending on the relative position between the PV panel and the solar light direction,
one of the two LEDs will generate a stronger signal and the other LED a weaker one. In
principle, the stronger signal will indicate the movement direction of the PV panel, so as
to be normally oriented to the incident sun light rays and thus to have a maximum
conversion efficiency of light into electricity. The operation scheme of the experimental
model of the solar tracking system supposed the amplification of the two signals
generated by the two LEDs up to the value range of the analog inputs of IBL2403 drive
unit, at which were connected the two signals


The proposed solution, which uses two independent light intensity sensors and the
separate measurement of their output signals, has the following advantages: - - by
measuring each separate signal we can detect, for the maximum signal intensity of the
signal, if the light intensity is strong enough to justify the panel movement, which means
additional energy consumption, in the case that the maximum signal intensity is higher
than the minimum admitted values, an additional decision criterion of movement will be
determined by the difference between the signals from the two LEDs. Whenthis
difference becomes greater than an imposed limit, the command for a new movement of
the PV panel will be triggered and thus the panel will be oriented again in order to
achieve a better position with respect to the sun. Thus, the proposed solution will
remove the intermittent, frequent and unnecessary movements of the PV panel that
would entail a higher consumption of energy, and thus decreasing in this way the
conversion efficiency of the system. We should point out that when the motor is not
active, the power circuit of the IBL2403 drive unit can be completely deactivated, thus
minimizing in this way the energy consumption of the system

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9.1.5WORKING OF SOLAR TRACKING SYSTEM

The system contains two modules, one is tracking and the other is controlling module.
Tracking module which will take angular rotation with the help of DC gear motor in
synchronous with the starting position of the sun. As sun rises from East, it will also take
the angle according to the angle of raising sun. So it will continuously track the sun till
the sun sets in the West.

Initially when the supply from the power kit was drawn and given to all the components
of the control circuit and keyboard. When the power supply is switched ON the panel
comes to the original position and by the keypad switches the clock time in the LCD
screen can be setted by the keypad switches. K1, K2 and K3 are the switches of
keypad. K1 represents Increment switch, K2 represents Decrement switch and K3
represents Enable switch. Initially the panel stands at reference position 8:00AM and
according to the setting time the panel rotates with the help of brushless DC Gear
Motor.

Module is designed with efficient Microcontroller from ATMEL 89C51 which helps to
drive the tracking module at different instants. The keypad switches was connected to
the microcontroller through latch to the port2(Pins 2.6, 2.7,2.8) and microcontroller was
connected to the LCD screen through the pins(P1.4 to P1.7) and the LCD displays the
preset time.

DS1307 is the RTC(Real Time Clock) used to produce clock pulses through
microcontroller which connects the LCD display, displays the time.

L293D driver was connected to the DC Motor, microcontroller and 9V battery. The
pulses that was produced by the microcontroller helps to connect the DC supply to the
DC brushless motor.
The DC brushless motor was mounted on a separate stand and connected to a shaft
which rotates the solar panel given from the microcontroller based upon this gear motor
operates.

When the supply was given to the dc gear motor, according to the setting from keypad,
the solar panel reaches the set state from the initial position with one degree as one
second and after reaching the set position it covers every degree by one degree.

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10. PRONS AND CONS

10.1 PRONS:
1. Solar power is pollution free during use. Production end wastes and emissions are
manageable using existing pollution controls. End-of-use recycling technologies are
under development.
2. Facilities can operate with little maintenance after initial setup.
3. Solar electric generation is economically superior where grid connection or fuel
transport is difficult, costly or impossible.
4. When grid-connected, solar electric generation can displace the highest cost
electricity during times of peak demand can reduce grid loading.
5. Grid-connected solar electricity can be used locally thus reducing
transmission/distribution losses.
6. Once the initial capital cost of building a solar power plant has been spent, operating
costs are extremely low compared to existing power technologies.
7. The power obtained by solar tracking is almost constant over a period of time when
compared with the output obtained by a panel without tracking.


10.2 CONS:
1. Solar electricity is almost more expensive than electricity generated by other sources.
2. Solar electricity is not available at night and is less available in cloudy weather
conditions. Therefore, a storage or complimentary power system is required.
3. Limited power density.
4. Solar cells produce DC which must be converted to ACwhen used in currently
existing.

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11. CONCLUSION:

In recent years, the generation of electricity using solar technology has seen a
tremendous growth, in particular because of the economic considerations and smooth
operation of the solar panels. Even though the initial costs are high, but operation costs
and maintenance costs are low. Solar tracking system today offer an innovative method
to track the solar insolation and provide economic compatibility of the generation of
electric power where grid connections are difficult to setup and costly.
Here the tracking system is based on microcontroller with effective systematic operation
and the solar panel is rotated by the dc gear motor effectively.






11.1PRESENT CONTRIBUTION AND FUTURE SCOPE:


Here the data provided to the micro controller consists of single common day
irrespective of the rotation of the sun and the seasons.
Effective tracking system is achieved when the data considering the rotation of earth
with respective to sun is included in the micro controller.