Solar Project 2018.docx

1

TABLE OF CONTENTS S.No.

Contents

Page No

1

Introduction

4

2

Block Diagram and its Description

6

2.1

Basic Block Diagram

6

2.2

Block Diagram Description

6

3

Component used Part – A

8

3.1

Voltage Regulator

9

3.2

LDR (Light Dependent Resistors)

20

4

Components Used Part – B

24

4.1

Lead Acid Battery

25

4.2

Stepper Motor

27

4.3

Solar Panel

34

4.4

Micro Controller AT89C2051

37

4.5

LED

44

5

Testing & Result

45

6

Future Scope

46

7

Applications

47

8

Conclusion

48

9

References

49

2

LIST OF FIGURES S. No.

Figure Name

Page No

1

Block Diagram of Solar Tracking System

6

2

Series Voltage Regulator Circuit

11

3

Shunt Voltage Regulator

12

4

Switching Voltage Regulator

13

5

Electronic Voltage Regulator

18

6

LDR Diagram

20

7

LDR Circuit Symbol

20

8

LDR Controlled Transistor Circuit

22

9

Stepper Motor

28

10

Stepper Motor Driver Circuit Diagram

32

11

Solar Panel

35

12

Pin Diagram

38

13

Block Diagram of Micro Controller

39

14

LED Diagram

41

15

Flash Memory

42

16

Flash Programming Characteristics

43

17

Electronic Circuit Diagram

44

18

PCB Layout for MCU

44

3

COMPONENTS LIST 1 R1~7

-10K

[BROWN, BLACK, ORANGE]

(7Nos)

2 R8~13

-220E

[RED, RED, BROWN]

(6Nos)

3 R14

-1K

[BROWN, BLACK, RED]

4 R15 ~17

-5 MM LDR [Light Sensor]

(3Nos)

5 PR1~3

-10K PRESET

(3Nos)

6 C1, 7

-100KPF DISC (0.1 UF/104)

(2Nos)

7 C2

-10UF / 25V Electrolytic

8 C3, 4

-33PF Ceramic Disc

9 C5

-1000UF / 16 V Electolytic

10C6

-47 UF / 25V Electrolytic

11 X1

-11.0592 MHZ Crystal

12 D1

- 1N4007 Diode

13 L1 ~6

- 3 mm OR 5 mm RED LED

(2Nos)

(6Nos)

14 L7

- 3mm OR 5 mm GREEN LED

15 U1

- AT89C2051 – MICROCONTROLLER

16 U2

- L293D MOTOR DRIVER

17 U3

- LM339 – COMPARATOR

18 U4

- LM 7805 - +5V Voltage Regulator

19 CN1

- 2 PIN SCREW TERMINALS BLOCK

20 1Nos

-20 PIN IS SOCKET FOR U1

21 1Nos

-16 PIN IS SOCKET FOR U2

22 1Nos

-14 PIN IC SOCKET FOR U3/ 30 RPM DC GEARED MOTOR

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CHAPTER: - 1 Introduction of Project

Introduction A 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 Solar Tracking System is made as a prototype to solve the problem. It is completely automatic and keeps the panel in front of sun until that is visible. The unique feature of this system is that instead of taking the earth as its reference, it takes the sun as a guiding source. Its active sensors constantly monitor the sunlight and rotate the panel towards the direction where the intensity of sunlight is maximum. In case the sun gets invisible e.g. in cloudy weather, then without tracking the sun the Solar Tracker keeps rotating the panel in opposite direction to the rotation of earth. But its speed of rotation is same as that of earth’s rotation. Due to this property when after some time e.g. half an hour when the sun again gets visible, the solar panel is exactly in front of sun.

This is a power generating method from sunlight. This method of power generation is simple and is taken from natural resource. This needs only, maximum sunlight to generate power. This project helps for power generation by setting the equipment to get maximum sunlight automatically. This system is tracking for maximum intensity of light.

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When there is decrease in intensity of light, this system automatically changes its direction to get maximum intensity of light.

A 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 Solar Tracking System is made as a prototype to solve the problem. It is completely automatic and keeps the panel in front of sun until that is visible. The unique feature of this system is that instead of taking the earth as its reference, it takes the sun as a guiding source. Its active sensors constantly monitor the sunlight and rotate the panel towards the direction where the intensity of sunlight is maximum. The power generated from this process is then stored in a lead acid battery and is made to charge an emergency light and is made to glow during night.

The design of the Solar Tracker requires many components. The design and construction of it could be divided into five main parts, each with their main function. They are: 1. Methods of Tracker Mount, 2. Methods of Drives, 3. Sensor and Sensor Controller, 4. Motor and Motor Controller, 5. Tracker Solving Algorithm

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CHAPTER: - 2 BLOCK DIAGRAM AND ITS DESCRIPTION

2.1

Basic Block Diagram

Our design of Solar Tracker is to develop and implement a simplified diagram of a horizontal- axis and active tracker method type of solar tracker fitted to a panel. It will be able to navigate to the best angle of exposure of light from the torchlight. A pair of sensors is used to point the East and West of the location of the light. A scaled-down model of a prototype will be designed and built to test the workability of the tracking system. The center of the drive is a DC motor. Figure shows a schematic diagram of a horizontal-axis solar tracker. This will be controlled via microcontroller program. The designed algorithm will power the motor drive after processing the feedback signals from the sensor array.

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HARDWARE REQUIREMENTS:

8051 series Microcontroller, Dummy Solar Panel, Stepper Motor, Voltage Regulator, Diodes, Relay driver IC, Transformer. SOFTWARE REQUIREMENTS:

Keil compiler Languages: Embedded C or Assembly

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CHAPTER 3:COMPONENTS USED-PART A

3.1 VOLTAGE REGULATOR A voltage regulator is used to regulate voltage level. When a steady, reliable voltage is needed, then voltage regulator is the preferred device. It generates a fixed output voltage that remains constant for any changes in an input voltage or load conditions. It acts as a buffer for protecting components from damages. A voltage regulator is a device with a simple feed-forward design and it uses negative feedback control loops. There are mainly two types of voltage regulators: Linear voltage regulators and switching voltage regulators; these are used in wider applications. Linear voltage regulator is the easiest type of voltage regulators. It is available in two types, which are compact and used in low power, low voltage systems. Let us discuss about different types of voltage regulators.

Types of Voltage Regulators and Their Working Principle

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Basically, there are two types of Voltage regulators: Linear voltage regulator and switching voltage regulator. There are two types of linear voltage regulators: Series and Shunt.

There are three types of switching voltage regulators: Step up, Step Down and Inverter voltage regulators. Linear Regulator

Linear regulator acts like a voltage divider. In Ohmic region, it uses FET. The resistance of the voltage regulator varies with load resulting in constant output voltage. Advantages of linear voltage regulator Gives a low output ripple voltage Fast response time to load or line changes Low electromagnetic interference and less noise Disadvantages of linear voltage regulator

Efficiency is very low Requires large space – heat sink is needed

Voltage above the input cannot be increased

Series Voltage Regulator

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A series voltage regulator uses a variable element placed in series with the load. By changing the resistance of that series element, the voltage dropped across it can be changed. And, the voltage across the load remains constant.

The amount of current drawn is effectively used by the load, this is the main advantage of the series voltage regulator. Even when the load does not require any current, the series regulator does not draw full current.Therefore a series regulator is considerably more efficient than shunt voltage regulator.

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Series Voltage Regulator Circuit Series Voltage Regulator Circuit

A shunt voltage regulator works by providing a path from the supply voltage to ground through a variable resistance. The current through the shunt regulator is diverted away from the load and flows uselessly to the ground, making this form usually less efficient than the series regulator.

It is,

however, simpler, sometimes consisting of just a voltage reference diode, and is used in very low-powered circuits where in the wasted current is too small to be of concern. This form is very common for voltage reference circuits. A shunt regulator can usually only sink (absorb) current.

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SHUNT VOLTAGE REGULATOR

Applications of Shunt Regulators

Shunt regulators are used in:

 Low Output Voltage Switching Power Supplies  Current Source and Sink Circuits  Error Amplifiers  Adjustable Voltage or Current Linear and Switching Power supplies Voltage  Monitoring  Analog and Digital Circuits that require precision references  Precision current limiters

SWITCHING VOLTAGE REGULATOR;

A switching regulator rapidly switches a series device on and off. The switch’s duty cycle sets the amount of charge transferred to the load. This is controlled by a feedback mechanism similar to that of a linear regulator. Switching regulators are efficient because the series element is either fully conducting or switched off because it dissipates almost no power. Switching regulators are able to generate output voltages that are higher than the input voltage or of opposite polarity, unlike linear regulators.

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Switching Voltage Regulator

Switching Voltage regulator switches on and off rapidly to alter the output. It requires a control oscillator and also charges storage components. In a switching regulator with Pulse rate Modulation varying frequency, constant duty cycle and noise spectrum imposed by PRM vary: it is more difficult to filter out that noise. A switching regulator with pulse width modulation, constant frequency, varying duty cycle, is efficient and easy to filter out noise. In a switching regulator, continuous mode current through an inductor never drops to zero. It gives better performance when the output current is low. Switching Topologies

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It has two types of topologies; Dielectric isolation and Non – isolation. Advantages of Switching Topologies The main advantages of a switching power supply are efficiency, size, and weight. It is also a more complex design, which is capable of handing higher power efficiency. Switching voltage regulator can provide output, which is greater than or less than or that inverts the input voltage. Disadvantages of Switching Topologies  Higher output ripple voltage  Slower transient recovery time popular pages  EMI produces very noisy output ; Very expensive STEP UP VOLTAGE REGULATOR: Step-up switching converters, also called boost switching regulators, provides a higher voltage output by raising the input voltage. The output voltage is regulated, as long as the power drawn is within the output power specification of the circuit. For driving strings of LEDS. Step up switching voltage regulator is used.

Step Up Voltage Regulator

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Assume Lossless circuit Pin = Pout (input and output powers are same) Then V

in Iin = Vout Iout , Iout / Iin = (1-D)

From this, it is inferred that in this circuit  Powers remain same  Voltage increases  Current decreases  Equivalent to DC transformer

Step Down (Buck) Voltage Regulator

It lowers the input voltage

If input power is equal to output power, then P

in = Pout; Vin Iin = Vout Iout,

Iout / Iin = Vin /Vout = 1/D

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Step down converter is equivalent to DC transformer wherein the turns ratio is in the range of 0-1. Step Up/Step down (Boost/Buck)

It is also called Voltage inverter. By using this configuration, it is possible to raise, lower or invert the voltage as per the requirement.  Output voltage is of opposite polarity of the input.  This is achieved by VL forward – biasing reverse biased diode during the odd times, producing current and charging the capacitor for voltage production during the off times.

Step Up/step Down Voltage Regulator

Alternator Voltage Regulator Alternators produce the current that is required to meet a vehicle’s electrical demands when the engine runs. It also replenishes the energy which is used to start the vehicle. An alternator has the ability to produce more current at

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lower speeds than the DC generators that were once used by most of the vehicles. Alternator has two parts.

Alternator Voltage Regulator Stator – This is a stationary component, which does not move. It contains a set of electrical conductors wound in coils over an iron core. Rotor / Armature – This is the moving component that produces a rotating magnetic field by any one of the following three ways: (i) induction (ii) permanent magnets (iii) using an exciter. Electronic Voltage Regulator A simple voltage regulator can be made from a resistor in series with a diode (or series of diodes). Due to the logarithmic shape of diode V-I curves, the voltage across the diode changes only slightly due to changes in current drawn or changes in the input. When precise voltage control and efficiency are not important, this design may work fine.

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Electronic Voltage Regulator

Transistor Voltage Regulator: Electronic voltage regulators have astable voltage reference source that is provided by the Zener diode, which is also known as reverse breakdown voltage operating diode. It maintains a constant DC output voltage. The AC ripple voltage is blocked, but filter cannot be blocked. Voltage regulator also has an extra circuit for short circuit protection, and current limiting circuit, over voltage protection, and thermal shutdown.

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Transistor Voltage Regulator

This is all about different types of voltage regulators and their working principle. We believe that the information given in this article is helpful for you for a better understanding of this concept. Furthermore, for any queries regarding this article or any help in implementing electrical and electronics projects, you can approach us by commenting in the comment section below. Here is a question for you – Where will we use an alternator voltage regulator?

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3.2 LDR (Light Dependent Resistors): An LDR is a component that has a (variable) resistance that changes with the light intensity that falls upon it. This allows them to be used in light sensing circuits

A typical LDR

LDR Circuit Symbol

Variation in resistance with changing light intensity

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Typical LDR resistance vs light intensity graph The most common type of LDR has a resistance that falls with an increase in the light intensity falling upon the device (as shown in the image above). The resistance of an LDR may typically have the following resistances: Daylight = 5000Ω Dark = 20000000Ω

You can therefore see that there is a large variation between these figures. If you plotted this variation on a graph you would get something similar to that shown by the graph shown above.

Applications of LDRs There are many applications for Light Dependent Resistors. These include:

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Lighting switch The most obvious application for an LDR is to automatically turn on a light at a certain light level. An example of this could be a street light or a garden light. Camera shutter control LDRs can be used to control the shutter speed on a camera. The LDR would be used to measure the light intensity which then adjusts the camera shutter speed to the appropriate level. Example - LDR controlled Transistor circuit

LDR controlled transistor circuit The circuit shown above shows a simple way of constructing a circuit that turns on when it goes dark. In this circuit the LDR and the other Resistor form a simple 'Potential Divider' circuit, where the centre point of the Potential Divider is fed to the Base of the NPN Transistor. When the light level decreases, the resistance of the LDR increases. As this resistance increases in relation to the other Resistor, which has a fixed resistance, it causes the voltage dropped across the LDR to also increase.

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When this voltage is large enough (0.7V for a typical NPN Transistor), it will cause the Transistor to turn on. The value of the fixed resistor will depend on the LDR used, the transistor used and the supply voltage. Project kits and components We have an electronic kit which utilises an LDR to detect lowering light levels and light a colour changing LED once it gets dark. This is a great example of an LDR in action. We also sell two different sizes of light dependant resistor, see below for more details.

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CHAPTER: - 4 COMPONENT USED-PART B 4.1 Lead Acid Battery: The lead acid battery uses the constant current constant voltage (CC/CV) charge method. A regulated current raises the terminal voltage until the upper charge voltage limit is reached, at which point the current drops due to saturation. The charge time is 12–16 hours and up to 36–48 hours for large stationary batteries. With higher charge currents and multi-stage charge methods, the charge time can be reduced to 8–10 hours; however, without full topping charge. Lead acid is sluggish and cannot be charged as quickly as other

battery

systems.

(See BU-202:

New

Lead

Acid

Systems.)

Lead acid batteries should be charged in three stages, which are [1] constant-current charge, [2] topping charge and [3] float charge. The constantcurrent charge applies the bulk of the charge and takes up roughly half of the required charge time; the topping charge continues at a lower charge current and provides saturation, and the float charge compensates for the loss caused by

self-discharge.

During the constant-current charge, the battery charges to about 70 percent in 5–8 hours; the remaining 30 percent is filled with the slower topping charge that lasts another 7–10 hours. The topping charge is essential for the wellbeing of the battery and can be compared to a little rest after a good meal. If continually deprived, the battery will eventually lose the ability to accept a full charge and the performance will decrease due to sulfa ion. The float

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charge in the third stage maintains the battery at full charge. Figure 1 illustrates these three stages.

Figure 1: Charge stages of a lead acid battery. The battery is fully charged when the current drops to a set low level. The float voltage is reduced. Float charge compensates for self-discharge that all batteries exhibit. The switch from Stage 1 to 2 occurs seamlessly and happens when the battery reaches the set voltage limit. The current begins to drop as the battery starts to saturate; full charge is reached when the current decreases to 3–5 percent of the Ah rating. A battery with high leakage may never attain this low saturation current, and a plateau timer takes over to end the charge.

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The correct setting of the charge voltage limit is critical and ranges from 2.30V to 2.45V per cell. Setting the voltage threshold is a compromise and battery experts refer to this as “dancing on the head of a needle.” On one hand, the battery wants to be fully charged to get maximum capacity and avoid sulfa ion on the negative plate; on the other hand, over-saturation by not switching to float charge causes grid corrosion on the positive plate. Temperature changes the voltage and this makes “dancing on the head of a needle” more difficult. A warmer ambient requires a slightly lower voltage threshold and a colder temperature prefers a higher setting. Chargers exposed to temperature fluctuations include temperature sensors to adjust the charge voltage

for

optimum

charge

efficiency.

The charge temperature coefficient of a lead acid cell is –3mV/°C. Establishing 25°C (77°F) as the midpoint, the charge voltage should be reduced by 3mV per cell for every degree above 25°C and increased by 3mV per cell for every degree below 25°C. If this is not possible, it is better to choose a lower voltage for safety reasons. Table 2 compares the advantages and

limitations

of

various

peak

voltage

settings.

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4.2 Stepper Motor

A stepper motor is an electromechanical device it converts electrical power into mechanical power. Also it is a brushless, synchronous electric motor that can divide a full rotation into an expansive number of steps. The motor’s position can be controlled accurately without any feedback mechanism, as long as the motor is carefully sized to the application. Stepper motors are similar to switched reluctance motors. The stepper motor uses the theory of operation for magnets to make the motor shaft turn a precise distance when a pulse of electricity is provided. The stator has eight poles, and the rotor has six poles. The rotor will require 24 pulses of electricity to move the 24 steps to make one complete revolution.

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Another way to say this is that the rotor will move precisely 15° for each pulse of electricity that the motor receives.

Stepper motor Types of Stepper Motor: There are three main types of stepper motors, they are:

1. Permanent magnet stepper 2. Hybrid synchronous stepper 3. Variable reluctance stepper Permanent Magnet Stepper Motor:

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Permanent magnet motors use a permanent magnet (PM) in the rotor and operate on the attraction or repulsion between the rotor PM and the stator electromagnets. Variable Reluctance Stepper Motor: Variable reluctance (VR) motors have a plain iron rotor and operate based on the principle that minimum reluctance occurs with minimum gap, hence the rotor points are attracted toward the stator magnet poles. Hybrid Synchronous Stepper Motor: Hybrid stepper motors are named because they use a combination of permanent magnet (PM) and variable reluctance (VR) techniques to achieve maximum power in a small package size. Advantages of Stepper Motor: 1. The rotation angle of the motor is proportional to the input pulse. 2. The motor has full torque at standstill. 3. Precise positioning and repeatability of movement since good stepper motors have an accuracy of 3 – 5% of a step and this error is non cumulative from one step to the next. 4. Excellent response to starting, stopping and reversing. 5. Very reliable since there are no contact brushes in the motor. Therefore the life of the motor is simply dependant on the life of the bearing. 6. The motors response to digital input pulses provides open-loop control, making the motor simpler and less costly to control.

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7. It is possible to achieve very low speed synchronous rotation with a load that is directly coupled to the shaft. 8. A wide range of rotational speeds can be realized as the speed is proportional to the frequency of the input pulses. Applications: 1. Industrial Machines – Stepper motors are used in automotive gauges and machine tooling automated production equipments. 2. Security – new surveillance products for the security industry. 3. Medical – Stepper motors are used inside medical scanners, samplers, and also found inside digital dental photography, fluid pumps, respirators and blood analysis machinery. 4. Consumer Electronics – Stepper motors in cameras for automatic digital camera focus and zoom functions. And also have business machines applications, computer peripherals applications. Operation of Stepper Motor: Stepper motors operate differently from DC brush motors, which rotate when voltage is applied to their terminals. Stepper motors, on the other hand, effectively have multiple toothed electromagnets arranged around a central gear-shaped piece of iron. The electromagnets are energized by an external control circuit, for example a microcontroller.

The stepper motor does not work on constant supply. It can only be worked on controlled and ordered power pulses. Before going any further we need to talk about UNIPOLAR and BIPOLAR stepper motor. As shown in figure in a UNIPOLAR stepper motor we can take the center tapping of both the phase windings for a common ground or for a common power. In first case we can take black and white for a common ground or power. In case 2 black is take

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for a common. In case3 orange black red yellow all come together for a common ground or power. Circuit Components 

+9 to +12 supply voltage



555 IC



1KΩ, 2K2Ω resistors



220KΩ pot or variable resistor



1µF capacitor, 100µF capacitor (not a compulsory, connected in parallel to power)



2N3904 or 2N2222 (no. of pieces depend on type of stepper if it’s a 2 stage we need 2 if it’s a four stage we need four)



1N4007 (no. of diodes is equal to no. of transistors



CD4017 IC.

Stepper Motor Driver Circuit Diagram and Explanation The figure shows the circuit diagram of two stage stepper motor driver. Now as shown in the circuit diagram the 555 circuit here is to generate

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clock or the square wave. The frequency of clock generation in this case cannot be kept constant so we need to get variable speed for the stepper motor. To get this variable speed a pot or a preset is paced in series with 1K resistor in branch between 6th and 7th pin. As the pot is varied the resistance in the branch changes and so the frequency of clock generated by 555.

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Now consider, for an example, all coils are magnetized at a time. The rotor experiences forces of equal magnitude from all around it and so it does not move. Because all are of equal magnitude and are expressing opposite direction. Now if the coil D only magnetized, the teeth 1 on rotor experiences an attractive force towards +D and teeth 5 of rotor experiences a repulsive force opposing the –D, theses two forces are represents an additive force clock wise. So the rotor moves to complete a step. After that it stops for the next coil to energize to complete next step. This goes on until the four steps are complete. For the rotor to rotate this cycle of pulsing must be going on.

As explained before, the preset is set to a value for a certain frequency of pulses. This clock is fed to the decade counter to get regular outputs from it. The outputs from decade counter are given to transistors to drive the high power coils of stepper motor in sequential order. The tricky part is, once a sequence is complete say 1, 2, 3, 4 the stepper motor completes four steps and so it is ready to start again however the counter has a capacity to go for 10 and so it goes on without interruption. If this happens the stepper motor must wait till the counter completes its cycle of 10 which is not acceptable. This is regulated by connecting RESET to Q4 so when counter goes forve count it resets itself and starts from one; this starts the sequence of stepper.

So this is how the stepper continuous it’s stepping and so the rotation happens. For a two stage the RESET pin must be connected to Q2 for the counter to resets itself in the third pulse. This way one can adjust the circuit to drive ten step stepper motor.

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4.3 SOLAR PANEL A photovoltaic (PV) module is a packaged, connect assembly of typically 6x10

photovoltaic solar

cells.

Photovoltaic

modules

constitute

the

photovoltaic array of a photovoltaic system that generates and supplies solar electricity in commercial and residential applications. Each module is rated by its DC output power under standard test conditions (STC), and typically ranges from 100 to 365 Watts (W). The efficiency of a module determines the area of a module given the same rated output – an 8% efficient 230 W module will have twice the area of a 16% efficient 230 W module. There are a few commercially available solar modules that exceed efficiency of 22%and reportedly also exceeding 24%. A single solar module can produce only a limited amount of power; most installations contain multiple modules. A photovoltaic system typically includes an array of photovoltaic modules, an inverter, a battery pack for storage, interconnection wiring, and optionally a solar tracking mechanism. The most common application of solar panels is solar water heating systems.

The price of solar power has continued to fall so that in many countries it is cheaper than ordinary fossil fuel electricity from the grid (there is "grid

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parity")

Photovoltaic modules use light energy (photons) from the Sun to

generate electricity through the photovoltaic effect. The majority of modules use wafer-based crystalline silicon cells or thin-film cells. The structural (load carrying) member of a module can either be the top layer or the back layer. Cells must also be protected from mechanical damage and moisture. Most modules are rigid, but semi-flexible ones based on thin-film cells are also available. The cells must be connected electrically in series, one to another. Externally, most of photovoltaic modules use MC4 connectors type to facilitate easy weatherproof connections to the rest of the system. Module electrical connections are made in series to achieve a desired output voltage or in parallel to provide a desired current capability. The conducting wires that take the current off the modules may contain silver, copper

or

other

non-magnetic

conductive

transition

metals.

Bypass diodes may be incorporated or used externally, in case of partial module shading, to maximize the output of module sections still illuminated. Some special solar PV modules include concentrators in which light is focused by lenses or mirrors onto smaller cells. This enables the use of cells with a high cost per unit area (such as gallium arsenide) in a cost-effective way. Solar panels also use metal frames consisting of racking components, brackets, reflector shapes, and troughs to better support the panel structure. Solar panel conversion efficiency, typically in the 20% range, is reduced by dust, grime, pollen, and other particulates that accumulate on the solar panel. "A dirty solar panel can reduce its power capabilities by up to 30% in high dust/pollen or desert areas", says Seamus Curran, associate professor of physics at the University of Houston and director of the Institute for

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NanoEnergy, which specializes in the design, engineering, and assembly of nanostructures. Paying to have solar panels cleaned is often not a good investment; researchers found panels that had not been cleaned, or rained on, for 145 days during a summer drought in California, lost only 7.4% of their efficiency. Overall, for a typical residential solar system of 5 kW, washing panels halfway through the summer would translate into a mere $20 gain in electricity production until the summer drought ends—in about 2 ½ months. For larger commercial rooftop systems, the financial losses are bigger but still rarely enough to warrant the cost of washing the panels. On average, panels lost a little less than 0.05% of their overall efficiency per day.

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4.4. MICRO CONTROller AT89C2051 Features •

Compatible with MCS®-51Products

•

2K Bytes of Reprogrammable Flash Memory – Endurance: 10,000 Write/Erase Cycles

•

2.7V to 6V Operating Range

•

Fully Static Operation: 0 Hz to 24 MHz

•

Two-level Program Memory Lock

•

128 x 8-bit Internal RAM

•

15 Programmable I/O Lines

•

Two 16-bit Timer/Counters

•

Six Interrupt Sources

•

Programmable Serial UART Channel

•

Direct LED Drive Outputs

•

On-chip Analog Comparator

•

Low-power Idle and Power-down Modes

•

Green (Pb/Halide-free) Packaging Option

. Description The AT89C2051 is a low-voltage, high-performance CMOS 8-bit microcomputer with 2K bytes of Flash programmable and erasable readonly memory (PEROM). The device is manufactured using Atmel’s highdensity nonvolatile memory technology and is compatible with the industry-standard MCS-51 instruction set. By combining a versatile 8-bit CPU with Flash on a monolithic chip, the Atmel AT89C2051 is a power- ful microcomputer which provides a highly-flexible and cost-effective solution to

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many embedded control applications. The AT89C2051 provides the following standard features: 2K bytes of Flash, 128 bytes of RAM, 15 I/O lines, two 16-bit timer/counters, a five vector two-level interrupt architecture, a full duplex serial port, a precision analog comparator, on-chip oscillator and clock circuitry. In addition, the AT89C2051 is designed with static logic for opera- tion down to zero frequency and supports two software selectable power saving modes. The Idle Mode stops the CPU while allowing the RAM, timer/counters, serial port and interrupt system to continue functioning. The power-down mode saves the RAM contents but freezes the oscillator disabling all other chip functions until the next hardware reset. 2. 2.1

Pin Configuration 20-lead PDIP/SOIC RST/VPP

1

20 VCC

(RXD) P3.0

2

19 P1.7

(TXD) P3.1

3

18 P1.6

XTAL2

4

17 P1.5

XTAL1

5

16 P1.4

(INT0) P3.2

6

15 P1.3

(INT1) P3.3

7

14 P1.2

(TO) P3.4

8

13 P1.1 (AIN1)

(T1) P3.5

9

12 P1.0 (AIN0)

10

11 P3.7

GND

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Block Diagram

3. Oscillator Characteristics The XTAL1 and XTAL2 are the input and output, respectively, of an inverting amplifier which can be configured for use as an on-chip oscillator, as shown in Figure 5-1. Either a quartz crystal or ceramic resonator may be used. To drive the device from an external clock source, XTAL2 should be left unconnected while XTAL1 is driven as shown in Figure 5-2. There are no requirements on the duty cycle of the external clock signal, since the input to the internal clocking circuitry is through a divide-by-two flip-flop, but minimum and maximum

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voltage high and low time specifications must be observed.

Oscillator Connections

Note:

C1, C2 = 30 pF 10 pF for Crystals

= 40 pF 10 pF for Ceramic Resonators

External Clock Drive Configuration

3. Special Function Registers A map of the on-chip memory area called the Special Function Register (SFR) space is shown in the table below. Note that not all of the addresses are occupied, and unoccupied addresses may not be implemented on the chip. Read accesses to these

41

addresses will in general return random data, and write accesses will have an indeterminate effect. User software should not write 1s to these unlisted locations, since they may be used in future products to invoke new features. In that case, the reset or inactive values of the new bits will always be 0. Programming the Flash Memory

PP

Verifying the Flash Memory

42

4.

5. Flash Programming and Verification Characteristics Symbol

Parameter

Min

Max

Units

VPP

Programming Enable Voltage

11.5

12.5

V

IPP

Programming Enable Current

250

µA

tDVGL

Data Setup to PROG Low

1.0

µs

tGHDX

Data Hold after PROG

1.0

µs

tEHSH

P3.4 (ENABLE) High to VPP

1.0

µs

tSHGL

VPP Setup to PROG Low

10

µs

tGHSL

VPP Hold after PROG

10

µs

tGLGH

PROG Width

1

tELQV

ENABLE Low to Data Valid

tEHQZ

Data Float after ENABLE

tGHBL

110

µs

1.0

µs

1.0

µs

PROG High to BUSY Low

50

ns

Twc

Byte Write Cycle Time

2.0

ms

tBHIH

RDY/BSY\ to Increment Clock Delay

1.0

µs

tIHIL

Increment Clock High

200

ns

0

43

TO

LDR2

LOR3

12V DC

MOTOR

LDF:l «5£1LOR DETECTION_

.

PCBLAYOUTFORMCUBASEDSOLARTRACKINGSYS ,.

TRACK LAY OUT PCB LAYOUT FOR MCU BASED SOLAR TRACKING SYS

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4.5 LED;A light – emitting diode (LED) is a two-lead semiconductor light source. It is a P- n junction diode that emits light when activated. When a suitable current is applied to the leads, electrons are able to recombine with electron holes within the device, releasing energy in the form of photons. This effect is called electroluminescence, and the color of the light (corresponding to the energy of the photon) is determined by the energy band gap of the semiconductor. LED s are typically small (less than 1 mm2) and integrated optical components may be used to shape the radiation pattern.

Light Emitting diode

45

CHAPTER: - 5 TESTING AND RESULTS We started our project by making power supply. That is easy for us but when we turn toward the main circuit, there are many problems and issues related to it, which we faced, like component selection, which components is better than other and its feature and cost wise We had issues with better or correct result, which we desired. And also the software problem. We also had some soldering issues which were resolved using continuity checks performed on the hard ware.

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CHAPTER – 6 FUTURE SCOPE The land space required to install a solar plant with solar panel is quite large and that land space remains occupied for many years altogether and cannot be used for other purposes. Energy production is quite low compared to other forms of energy. Solar panels require considerable maintenance as they are fragile and can be easily damaged. So extra expenses are incurred as additional insurance costs. In solar energy sector, many large projects have been proposed in India. The Desert has some of India’s best solar power projects, estimated to generate 700 to 2,100 GW.

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CHAPTER – 7 APPLICATIONS

1. It is used in Industrial purpose. 2. It is used in agriculture purpose. 3. It is used in homemade purpose. 4. It is used to generate the bulk amount of energy. 5. It is used in some of factories.

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CHAPTER -8 CONCLUSION In this paper of solar tracking system I reached up to the movement of stepper motor. Due to higher cost we couldn’t afford a solar cell. Nonetheless, the working will be same if we connect a solar cell, as all parameters have been achieved. The aim of my paper was movement of motor by signal from light sensing circuit when the intensity of light is maximum, which has been successfully achieved.

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CHAPTER - 9

REFERENCES [1] Energy Engineering and Management – Amlan Chakraborti – PHI. [2] Energy: Management, Supply and conservation – Dr. Clive Beggs. [3] Energy Conservation: Success and Failures – John C. Sawhill, Richard Cotton – Brookings Institution Press. [4] Handbook of Energy Conservation – H.M. Robert, J.M. Collins – Alken Publishing Unit. [5] Electric Machines – D.P.Kothari, I.J. Nagrath – Tata Mc.Graw Hill Education. [6] Electrical Machines – M.V.Deshpande – Jain Book Agency. [7] Electrical Machines ( AC & DC Machines ) – J.B.Gupta – Jain Book Agency. [8] Digital Electronics And Logic Design – B. Somanathan Nair – PHI Learning Pvt. Ltd. [9] Digital Electronics and Microprocessors – R.P.Jain – Mc. Graw Hill Education. [10] Digital and Microprocessor Fundamentals: Theory and Applications – William Kleitz – Prentice Hall.