PWM Based DC Motor Speed Control Using Microcontroller [NEC-022]

PWM BASED DC MOTOR SPEED CONTROL USING MICROCONTROLLER

1

INTRODUCTION

Today’s industries are inreasin!"y de#andin! $roess auto#ation in a"" setors% Auto#ation resu"ts into &etter 'ua"ity( 'ua"ity( inreased $rodution $rodution an redued redued osts% T)e *aria&"e *aria&"e s$eed dri*es( +)i) an ontro" t)e s$eed o, A%C-D%C #otors( are indis$ensa&"e ontro""in! e"e#ents in auto#ation syste#s% De$endin! on t)e a$$"iations( so#e o, t)e# are ,i.ed s$eed and so#e o, t)e *aria&"e s$eed dri*es% T)e *aria&"e s$eed dri*es( ti"" a ou$"e o, deades &a/( )ad *arious "i#itations( su) as $oor  e,,iienies( e,,iienies( "ar!er s$ae( "o+er s$eeds( et%( 0o+e*er( 0o+e*er( t)e ad*ent ad*ent $o+er e"etroni e"etroni de*ies de*ies su) as $o+er #os,ets( i!&ts et%( and a"so +it) t)e introdution o, #iro ontro""ers +it) #any ,eatures on t)e sa#e si"ion +a,er( trans,or#ed t)e sene o#$"ete"y and today +e )a*e *aria&"e *aria&"e s$eed dri*e syste#s syste#s +)i) are not on"y in t)e s#a""er in si2e &ut a"so *ery e,,iie e,,iient( nt( )i!)"y )i!)"y re"ia&" re"ia&"ee and #eetin #eetin! ! a"" t)e strin!e strin!ent nt de#and de#andss o, *ariou *ariouss indust industrie riess o,  #odern era%

ECE De$art#ent( SRMGPC( Lu/no+

PWM BASED DC MOTOR SPEED CONTROL USING MICROCONTROLLER

3

INTERFACING WITH DC MOTOR 

DC MOTOR - A DC #otor is any o, a "ass o, e"etria" #a)ines t)at on*erts diret urrent e"etria" $o+er into #e)ania" $o+er% T)e #ost o##on ty$es re"y on t)e ,ores  $rodued &y #a!neti ,ie"ds% DC Motors are s#a""( ine.$ensi*e and $o+er,u" #otors used +ide"y in ro&otis ,or t)eir s#a"" si2e and )i!) ener!y out% A ty$ia" DC #otor o$erates at s$eeds t)at are ,ar too )i!) s$eed to &e use,u"( and tor'ue t)at are too "o+% Gear’s redue t)e s$eed o, #otor and inreases t)e tor'ue%

INTERFACING 

T)e #a.i#u# urrent t)at an &e soured or sun/ ,ro# 4561

#iroontro""er is 16 #A at 67% But a DC #otor need urrents #u) #ore t)an t)at and it need *o"ta!es 87( 137 et de$endin! u$on t)e ty$e o, #otor used% Anot)er $ro&"e# is t)at t)e &a/ e#, $rodued &y t)e #otor #ay a,,et t)e $ro$er ,untionin! o, t)e #iroontro""er% Due to t)ese reasons +e an’t onnet a DC #otor diret"y to a #iroontro""er% 0ene IC L39:D is used to inter,ae t)e DC #otor +it) #iroontro""er 4561%

INTERFACING OF DC MOTOR WITH MICROCONTROLLER 8051 USING IC L293D

ECE De$art#ent( SRMGPC( Lu/no+

PWM BASED DC MOTOR SPEED CONTROL USING MICROCONTROLLER

:

DESCRIPTION OF DRIVER CIRCUIT

T)ere are t+o in$uts A and B% T)es t+o in$uts to!et)er ,or# ; o#&inations%



CASE 1

W)en in$ut A < 5 =)i!)> and in$ut B < 5 ="o+> t)en t)e DC #otor sto$s rotatin! or &rea/s do+n% ECE De$art#ent( SRMGPC( Lu/no+

PWM BASED DC MOTOR SPEED CONTROL USING MICROCONTROLLER

;

CASE 2 W)en in$ut A < 5 ="o+> and in$ut B < 1 =)i!)> t)en t)e DC #otor starts rotatin! in anti"o/+ise diretion%



CASE 3

W)en in$ut A < 1 =)i!)> and in$ut B < 5 ="o+> t)en t)e DC #otor starts rotatin! in "o/+ise diretion%



CASE 4

W)en in$ut A < 1 =)i!)> and in$ut B < 1 =)i!)> t)en t)e DC #otor sto$s rotatin! or   &rea/s do+n%

ECE De$art#ent( SRMGPC( Lu/no+

PWM BASED DC MOTOR SPEED CONTROL USING MICROCONTROLLER

PROGRAM TO INTERFACE DC MOTOR WITH 8051 ?in"ude@re!63%) ?in"ude@stdio%) *oid de"ay=*oid> s&it #otor$in1 < P35 s&it #otor$in3 < P31 *oid #ain=>  do  #otor$in1 < 1 #otor$in3 < 5 --Rotates Motor Anti C"o/+ise de"ay=> #otor$in1 < 1 #otor$in3 < 1 --Sto$s Motor  de"ay=> #otor$in1 < 5 #otor$in3 < 1 --Rotates Motor C"o/+ise de"ay=> #otor$in1 < 5

ECE De$art#ent( SRMGPC( Lu/no+

6

PWM BASED DC MOTOR SPEED CONTROL USING MICROCONTROLLER

#otor$in3 < 5 --Sto$s Motor  de"ay=> F +)i"e=1> F *oid de"ay=>  int i( ,or=i  ,or= F F F

ECE De$art#ent( SRMGPC( Lu/no+

8

PWM BASED DC MOTOR SPEED CONTROL USING MICROCONTROLLER



PWM TECHNIQUE FOR CONTROLLING SPEED OF DC MOTOR USING MICROCONTROLLER

PWM is a one$t +it) +)i) one an #odi,y t)e $u"se *o"ta!e *aryin! it ,ro# 5J duty y"e to 155J% Pu"se +idt) #odu"ation =PWM> is a #et)od ,or &inary si!na"s !eneration( +)i) )as 3 si!na" $eriods =)i!) and "o+>% T)e +idt) =W> o, ea) $u"se *aries &et+een 5 and t)e $eriod =T>% T)e #ain $rini$"e is ontro" o, $o+er &y *aryin! t)e duty y"e% 0ere t)e ondution ti#e to t)e "oad is ontro""ed% Let ,or a ti#e t1( t)e in$ut *o"ta!e a$$ears aross t)e "oad i%e% ON state and ,or t3 ti#e t)e *o"ta!e aross t)e "oad is 2ero% K T)e a*era!e *o"ta!e at out$ut is !i*en &y 7 a < 7#a.%  +)ere( TON