contents introduction description of the project- circuit diagram hardware description...

CONTENTSCONTENTSINTRODUCTIONINTRODUCTION

DESCRIPTION OF THE PROJECT- CIRCUIT DIAGRAMDESCRIPTION OF THE PROJECT- CIRCUIT DIAGRAM

HARDWARE DESCRIPTIONHARDWARE DESCRIPTION

MICROCONTROLLERSMICROCONTROLLERS

U.L.N 2003 LINEAR INTEGRATED CIRCUITU.L.N 2003 LINEAR INTEGRATED CIRCUIT

A/D CONVERTERA/D CONVERTER

STEPPER MOTORSTEPPER MOTOR

LCD UNITLCD UNIT

LM 555 TIMERLM 555 TIMER

SOFTWARE DESCRIPTIONSOFTWARE DESCRIPTION

INTRODUCTIONINTRODUCTION

SOURCE CODESOURCE CODE

APPLICATIONSAPPLICATIONS

DRAWBACKSDRAWBACKS

ADVANTAGESADVANTAGES

CONCLUSIONCONCLUSION

INTRODUCTIONINTRODUCTION

“SOLAR TRACKING SYSTEM” - used to control and set the moment of solar panels.

This system uses stepper motor to control the angle of rotation of the panels.

Rotation of stepper motor through the desired angle is achieved by using Keil cross compiler.

The basic idea of the project is to increase the efficiency of the solar systems.

The solar panel is made to rotate in all the directions facing the sunlight.

Tracks the maximum intensity position and rests in that position

DESCRIPTION OF THE DESCRIPTION OF THE PROJECTPROJECT

CIRCUIT DIAGRAMCIRCUIT DIAGRAM

HARDWARE DESCRIPTIONHARDWARE DESCRIPTION

Features of microcontroller:Features of microcontroller:

Compatible with MCS-51® Products

8K Bytes of In-System Programmable (ISP) Flash Memory

Endurance: 1000 Write/Erase Cycles

4.0V to 5.5V Operating Range

Fully Static Operation: 0 Hz to 33 MHz

256 x 8-bit Internal RAM

32 Programmable I/O Lines

Three 16-bit Timer/Counters

The AT89S52 is a low-power, high-performance CMOS 8-bit microcontroller

The device is manufactured using Atmel’s high-density non-volatile memory technology

Compatible with the industry-standard 80C51 instruction set and pin out.

PIN CONFIGURATIONPIN CONFIGURATION

ULN 2003 LINEAR INTEGRATED ULN 2003 LINEAR INTEGRATED CIRCUITCIRCUIT

DESCRIPTION:DESCRIPTION:

UTC(unisonic technologies co. ltd)

ULN 2003- high-voltage , high-current Darlington driver

Comprises of seven NPN Darlington pairs

Ideally suited for interfacing between low-level logic circuitry and multiple peripheral power loads

The series ULN2003A/L high-voltage , high-current Darlington arrays feature continuous load current ratings to 500mA for each of the seven drivers.

The ULN2003A/L have series input resistors selected for operation directly with 5V TTL or CMOS

The outputs are capable of sinking 500mA and will with stand at least 50V in the OFF state.

Outputs may be paralleled for higher load current capability.

The Darlington arrays are furnished in 16-pin Dual-in-line plastic package and 16-lead surface- mountable SOIC’s .

All devices are pinned with outputs opposite inputs to facilitate ease of Circuit board layout .

All devices are rated for operation over the temperature range of -20˚ C to 85˚ C .

FEATURES FEATURES

Output current (single output) 500mA MAX

High sustaining voltage output 50V MIN .

Output clamp diodes . Inputs compatible with various types of

logic . Dual In-Line Plastic Package or Small-

Outline IC Package.

PIN CONFIGURATIONSPIN CONFIGURATIONS

STEPPER MOTORSSTEPPER MOTORS

Stepper Motor is widely used in CNC

machine drives , robots, and wherever an

accurate positioning is required . In such

applications, step angle , direction , operating

modes( single coil or double coil),

Speed and position are important considerations.

WHAT IS A STEPPER MOTOR ?? WHAT IS A STEPPER MOTOR ?? Stepper motor is a simple dc motor with a permanent magnet rotor and a stator with armature consisting of coils.

These coils produce a magnetic field when suitable current flows through them this field produces a torque in the rotor which makes it rotate.

The step wise motion can be easily controlled by a stepper controller which is a simple circuit which takes digital logic and then uses it to turn the motor step wise .

Well these are a little more complicated to control than the simple DC motors but these provide exact step wise rotation with an overall turn of 1.8 degrees / step .

Driving Uni polar Stepper Motors Using Driving Uni polar Stepper Motors Using C51/C251 IntroductionC51/C251 Introduction

Stepper motors are commonly used in accurate

motion control.

They allow to control any motion with high precision

by counting the number of steps applied to the motor.

This application note describes how to drive a uni polar

stepper motor with the Programmable Counter Array of an

Atmel C51/C251 microcontroller

Most of systems controlling stepper motors are

embedded systems such as printer scanner or floppy disk

drive.

Identification of StepperIdentification of StepperMotorMotor

There are several types of stepper motors, these cannot be driven in the same way. In this application note, we have chosen to drive a unipolar stepper motor For more information you will find schemes to identify the other types of stepper motors.

Unipolar Stepper Motor Unipolar stepper motors are characterised by their center-tapped windings.

Variable Reluctance Variable reluctance stepper motor (also called hybrid motors) are characterized by one common lead.

Driving Uni polar Stepper MotorsDriving Uni polar Stepper Motors(ONE PHASE STEPS)(ONE PHASE STEPS)

TWO PHASES ON STEPSTWO PHASES ON STEPS

SOLAR PANELS AND SOLAR SOLAR PANELS AND SOLAR CELLSCELLS

LM555 Timer :LM555 Timer :General Description:General Description: The LM555 is a highly stable device for generating accurate time delays or oscillation . Additional terminals are provided for triggering or resetting if desired . In the time delay mode

of operation , the time is precisely controlled by one external

resistor and capacitor . For astable operation as an oscillator,the free

running frequency and duty cycle are accurately controlled with two external resistors and one capacitor. The circuit may be triggered and reset on falling waveforms , and the output circuit can source or sink up to 200mA or drive TTL circuits.

ASTABLE OPERATIONASTABLE OPERATION

If the circuit is connected as shown in Figure ( pins 2 and 6

Connected ) it will trigger itself and free run as a multivibrator.

The external capacitor charges through RA + RB and discharges

through RB. Thus the duty cycle may be precisely set by the ratio of these two resistors .

A/D CONVERTERA/D CONVERTER

FeaturesFeatures:: Easy interface to all microprocessors Operates ratiometrically or with 5 VDC or analog

span adjusted voltage reference No zero or full-scale adjust required 8-channel multiplexer with address logic 0V to 5V input range with single 5V power

supply Outputs meet TTL voltage level specifications Standard hermetic or molded 28-pin DIP package 28-pin molded chip carrier package

DESCRIPTIONDESCRIPTION

The ADC0808, data acquisition component is a monolithic, CMOS device with an 8-bit analog-to-digital converter , 8-channel multiplexer and microprocessor compatible control logic . The 8-bit A/D converter uses successive approximation as the conversion technique . The converter features a high impedance chopper stabilized comparator , a 256R voltage Divider with analog switch tree and a successive approximation register . The 8-channel multiplexer can directly access any of 8-single-ended analog signals .Easy interfacing to Microprocessors is provided by the latched and decoded multiplexer address inputs and latched TTL TRI-STATE® outputs .

PIN CONFIGURATIONPIN CONFIGURATION

LCD UNITLCD UNITFEATURES:FEATURES:

Interface with either 4-bit or 8-bit microprocessor.

Display data RAM (80 characters).

Character generator ROM(160 character patterns)

Character generator RAM(8 different user programmed

patterns)

Display data RAM and character generator RAM

may be accessed by the microprocessor.

Numerous instructions (Clear Display , Blink

Character , Cursor Shift , Display Shift, etc.)

Built-in reset circuit is triggered at power ON.

Built-in oscillator.

SOFTWARE DESCRIPTION:SOFTWARE DESCRIPTION: The C programming language is a general – purpose

programming language

C is not a big language and is not designed for any one particular area of application .

Its generality combined with its absence of restrictions makes C a convenient and effective programming solution for a wide variety of software tasks .

Many applications can be solved more easily and efficiently with C than with other more specialized languages.

The Cx51 Optimizing C Compiler is a complete

implementation of the American National Standards

Institute (ANSI) standard for the C language .

. Cx51 provides you with the flexibility of

programming in C and the code efficiency and speed of

assembly language .

Since Cx51 is a cross compiler standard libraries are

altered or enhanced to address the peculiarities of an

embedded target processor.

SOURCE CODESOURCE CODE

#include<reg52.h>

void lcd_string1(unsigned char *);

void lcd_string2(unsigned char *);

void lcd_command(unsigned char);

void lcd_data(unsigned char);

void lcd_init(void);

void lcd_delaybig(void);

void lcd_delaysmall(void);

void delay(void);

void delayvar(unsigned int);

void test(void);

void powinit(void);

void clkwise(int);

void aclkwise(int);

void timer0 (void);

void dispnum(unsigned char a);

unsigned char getadc( void);

void scan(void);

void main( void){powinit();test();while(1)

{timeout=10000;

toutstart=1;while(!toutend);toutend=0;toutstart=0;scan();}

 }

//LCD interface functionsvoid lcd_init()

{

 lcd_port=0;

RS=0;

RW=0;

EN=1;

EN=0;

lcd_delaybig();

lcd_command(0x38); //2 lines & 5x7 matrix

lcd_command(0x38); //2 lines & 5x7 matrix

lcd_command(0x0e); //Display on, cursor blinking

lcd_command(0x01); //Clear display screen

lcd_command(0x6); //Shift cursor to right

lcd_command(0x80); //Force cursor to beginning of 1st line

}

void lcd_command(unsigned char command){lcd_port=command;RS=0;RW=0;EN=1;EN=0;lcd_delaysmall();} void lcd_data(unsigned char lcddata){lcd_port=lcddata;RS = 1;RW = 0;EN = 1;EN = 0;lcd_delaysmall();}

void lcd_string1(unsigned char *p){

unsigned int i;lcd_command(0x80);for(i=0;i<16;i++)

lcd_data(' ');lcd_command(0x80);while(*p!=0)

{lcd_data(*p);p++;

}}void lcd_string2(unsigned char *p){ unsigned int i;

lcd_command(0xc0);for(i=0;i<16;i++)

lcd_data(' ');lcd_command(0xc0);while(*p!=0)

{lcd_data(*p);p++;

}}

void powinit(void)

{

EA=1;

ET0=1;

PT0=1;

TMOD=1;

TL0=0X2F; //2ms at 12 MHz

TH0=0XF8;

TR0=1;

stport=0;

adcport=0xff;

SOC=0;

EOC=1;

ALE=0;

//AI=0;

//BI=0;

//CI=0;

 toutstart=0;

toutend=0;

timeout=0;

curpos=5;

lcd_init();

}

void test(void)

{

lcd_string2("TEST");

clkwise(5);

aclkwise(5);

}

void clkwise(int psteps){unsigned char stval,st;int steps;  for(steps=0;steps<(psteps*2);steps++)

{ stval=0x10; for(st=0;st<4;st++)

{stport=stval;stval<<=1;delayvar(9000);

}}

}

void aclkwise(int psteps)

{

unsigned char stval,st;

int steps;

 for(steps=0;steps<(psteps*2);steps++)

{

stval=0x80;

for(st=0;st<4;st++)

{

stport=stval;

stval>>=1;

delayvar(9000);

}

}

}

void scan(void){ unsigned char i,maxval,maxpos,temppos;  aclkwise(curpos); for(curpos=0;curpos<10;curpos++)

{sundata[curpos]=getadc();clkwise(1);lcd_string1("SCANNING AT");dispnum(curpos);lcd_string2("VALUE IS ");dispnum(sundata[curpos]);

delayvar(0xaaaa);}

maxval=sundata[0]; maxpos=0;

for(i=1;i<10;i++)

{

if(maxval<sundata[i])

{

maxval=sundata[i];

maxpos=i;

}

  lcd_string1("MAX O/P AT: ");

lcd_data(maxpos+48);

lcd_string2("MAX O/P V: ");

dispnum(maxval);

temppos=curpos-maxpos;

curpos=maxpos;

aclkwise(temppos);

}

FLOW CHARTFLOW CHART

APPLICATIONSAPPLICATIONS

Solar tracking system is used in satellites as a Solar tracking system is used in satellites as a source of fuel.source of fuel.

It is used in solar thermal collector to collect heat.It is used in solar thermal collector to collect heat.

It is used in solar hot water panel that uses the It is used in solar hot water panel that uses the sun's energy to heat a fluid , which is used to sun's energy to heat a fluid , which is used to transfer the heat to a heat storage vessel.transfer the heat to a heat storage vessel.

It is used in water heaters.It is used in water heaters.

It is used in heat exchangers.It is used in heat exchangers.

It is used in solar power plants.It is used in solar power plants.

It is used for desalination of sea water.It is used for desalination of sea water.

It is used in inverters (AC to DC).It is used in inverters (AC to DC).

It is used in solar water pumps.It is used in solar water pumps.

DRAWBACKS

Tracker is affected by Tracker is affected by temporaltemporal variations in the variations in the atmospheric refractions caused by rain, cloud, etc.atmospheric refractions caused by rain, cloud, etc.

Thus, the system may give an erroneous detection in Thus, the system may give an erroneous detection in the direction of the sun, and lead to wrong positioning of the direction of the sun, and lead to wrong positioning of the solar panelthe solar panel.

ADVANTAGES

The tracking system is not constrained by the geographical The tracking system is not constrained by the geographical location of installation of the solar panel.location of installation of the solar panel.

It is designed for searching the maximum solar irradiance in It is designed for searching the maximum solar irradiance in the whole azimuth and tilt angle.the whole azimuth and tilt angle.

The operator interference is minimal because of not needing The operator interference is minimal because of not needing to be adjusted.to be adjusted.

CONCLUSIONCONCLUSION

To collect the greatest amount of energy from the sun, To collect the greatest amount of energy from the sun, solar panels must be aligned orthogonally to the sun. solar panels must be aligned orthogonally to the sun.

For this purpose, a new solar tracking technique based on For this purpose, a new solar tracking technique based on micro-controller was implemented and tested in this study. micro-controller was implemented and tested in this study.

There are several new solar cell concepts that aim at There are several new solar cell concepts that aim at making better use of the solar spectrum and achieve making better use of the solar spectrum and achieve much higher energy conversion efficienciesmuch higher energy conversion efficiencies