This document describes a solar tracking system that uses an 8051 microcontroller to automatically position a solar panel to track the sun from east to west for maximum sunlight exposure. It works by using light dependent resistors (LDRs) to sense the intensity of light and send signals to a stepper motor driver and stepper motor to adjust the panel's position. The system aims to maximize the amount of solar energy collected by keeping the panel perpendicular to the sun throughout the day. It provides economic and environmental benefits over fixed solar panels.

1. SOLAR TRACKING SYSTEM USING
8051 MICROCONTROLLER
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2. THE SOLAR OPTION:
 Solar energy is a very large, inexhaustible source of energy. The power from the sun
intercepted by the earth is approximately 1.8*1011MW, which is many thousands of times
larger than the present consumption rate on the earth of all commercial energy sources.
 Solar energy could supply all the present and future energy needs of the world on a
continuing basis. This makes it one of the most promising of the unconventional energy
sources.
 It has two other factors in the favour:
i. Firstly, unlike fossil fuels and nuclear power, it is environmentally clean source of
energy.
ii.Secondly, it is free and available in adequate quantities in almost all parts of the world
where people live. Also it has no heavy mechanical section and is free from noise.
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3. OBJECTIVE
 The aim of our projects is to utilize the maximum solar energy through solar panel. For this a digital
based automatic sun tracking system is proposed.
 The solar panel tracks the sun from east to west automatically for maximum intensity of light.
 Processes Involved are-:
i. To fabricate a Stepper motor control interfaced with driver circuit.
ii. To construct a model prototype solar cell movement system with a mechanical
assemble to move the panel from 180⁰ E to W.
iii.To design an electronic circuit to sense the intensity of light and to control stepper
motor driver for the panel movement.
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4. How the Tracker follow the Sun:
1.Sunrise "Wake- Up:
The Track Rack begins the day
facing west. As the morning
sun rises, the sun rays falls on
the LDR, it detects and sends
signal to stepper motor to turn
towards the east.
2. Mid-Morning:
As the sun rises, the LDR
also detect the angle, where
its getting maximum
efficiency and
correspondingly move
towards that direction.
3. Mid-Afternoon:
As the sun moves, the Track
Rack follows (at
approximately 15o per hour,
continually moving from one
side to another.
4. Sunset:
The Track Rack completes its
daily cycle facing west. It
remains in this position
overnight until it is
"awakened" by the rising sun
the following morning.
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5. BLOCK DIAGRAM5
MICROCONTROLLERLDR 2
POWER
SUPPLY
DRIVER
STEPPER
MOTOR
LDR 1
COMPARATOR

6. CIRCUIT DIAGRAM6

7. COMPONENTS USED:
 SOFTWARE:
 Embedded C programming.
 Keil C compiler.
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COMPONENT SPECIFICATIONS
1. Microcontroller AT89S52.
2. Voltage regulator 7812,7805.
3. Driver ULN2003.
4. LDR,LCD ---
5. Stepper Motor 7.5 degree per step
6. Transformer TRAN-2P2S
7. Crystal Oscillator 11.0592 MHz
8. Resistors 100Ω.
9. Capacitor 33pF, 1000uF.
10. Potentiometer 10KΩ(3).

8. POWER SUPPLY:8
 The aim is to design the power supply section which converts 230V AC in to 5V DC.
 We short listed to use Bridge rectifier, because half wave rectifier has less efficiency. Even though the
efficiency of full wave and bridge rectifier are the same, but as there is no requirement for any negative
voltage for our application, we gone with bridge rectifier.

9. WORKING WITH KEIL SOFTWARE:9

10. FUTURE ADVANCEMENTS:
More Sensitive Photo
resistors.
Comparing Efficiency
with Fixed Solar panel.
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11. ECONOMICALLY AFORDABLE:
 The attractive feature of the constructed prototype is the software solution of many
challenges regarding solar tracking system.
 The designed prototype requires only two photo resistors to sense the light, which
lessens the cost of the system.
 Power consumption of the system is negligible as ‘wait’ states are calculated perfectly
with the sun’s position.
 Another major problem of system initialization at the start of the day is solved through
a simple programming application. All these software based solution reduce the system
cost far more than all other systems proposed to date.
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12. CONCLUSION
 We presented a means of tracking the sun’s position with the help of
microcontroller. Specially, it demonstrates a working software solution for
maximizing solar cell output by positioning a solar panel at the point of maximum
light intensity.
 Moreover, the tracker can initialize the starting position itself which reduce the
need of any more photo resistors.
 Though the prototype has limitations in hardware areas as an initial set up, still it
provides an opportunity for improvement of the design methodology in future.
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13. THANK YOU
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