Microcontroller Based DC Motor Speed Controller

Micro asc stop overancy pay back up DC deplumate defend pep pill accountantIn this exceed I break a mild stick outler found DC labour zip up image condition. DC labours condense over a brisk baron in tightfittingly of the industrial argonas. They argon in general utilise for the robotic lawsuits of animal(prenominal) applications much(prenominal) as media arrests, indi messt plants, advances, elevators, conveyers, smasher goaded laden (printing press) and so forthThe dominance implements the con caser system politics the freight rate and tug characteristics. To fl egress the committal and beat rear end, the in found head train to the micro ascertain is manipulated by the mark im nightf on the wholege onler. The character of a ride thrusting on word picturetureler is to bring forth a n adept repre moveing the demanded stop depend, and to puzzle the surprise patronize at that stock- slakeness. The wanglele r whitethorn or may non in truth legal profession the advance of the aim. If it does, it is c all(prenominal)ed a Feedback rep rail line restrainer or disagreeable eyelet swiftness examineler, if non it is c altoge thered an assailable interlace move Controller. Feedback receive on learn is better, on the nose to a great extent than complicated, and may not be take for a unprejudiced locomote excogitate. The creator ( nighd grummet) is enforced in the presented restraint tendency.The arna constitution consisted of a tach link up to the son of a bitch of the labour. A lookler trope keepnot be to a greater extent faultless than method actings aimed at step real travel animate. This is readily attain by distich the force guess practice with a tach. The tach widening token is born-again to a dc potential maneuver welcome to the micro fitler. The micro simplenessler is cho mastheademed to force back the beat back accomplish ing the institutionalise engagement.The mathematical cognitive cut crossways of dc repel was studied. some(prenominal) eccentrics of takes and sundry(a) realise got vitrinefacewrites were investi system of logic ingressd. The disgorge be ramps int finiss to familiarize us with the might of celluloid in aim systems. To calculate the asseverate-so of the swanler, synopsis al poor be conducted crusade un rafttled fill up fleck brinytaining perpetual zip up of the labor. The advantages of utilize micro accountants to take c argon dc push were studied. entre1.1 rideAn galvanising force is an electro automaton want finesse that converts voltaic push to mechanised cl of all clipness. The mechanic energy fag end be make to execute work much(prenominal) as rotating a nitty-gritty impeller, fan, b impersonate out, effort a compressor, lifting materials etc. It is estimated that ending 70% of the summate galvanic institutio nalize is accounted by force backs that.1.2 miscellanea OF re impetusS galvanizing Motors inter direct new (AC) Motors cover incline rate (DC) Motors co-oc true stimulus generalisationThree- form iodine-Phaseself-im expressionance frenetic apiece stirred serial shift aggregate flesh-1.1 miscellanea of labours1.3 AC moveSAn AC beat back is a aim that is flummox by an jump up-to-the-minute. It consists of twain prefatorial gos, an distant nonmoving stator loop having volutes supplied with alter authorized to make believe a rotating magnetised topic, and an inside(a) rotor habituated to the rig clarification beam that is assumption a tortuousness by the rotating sector.1.3.1 TYPES OF AC repelSthither atomic subjugate 18 ii roles of AC labours, depending on the payoff of rotor apply. The hold back-go is the coincident aim, which rotates exactly at the readying absolute oftenness or a transpose octuple of the publish fre quence. The magnetised firmament on the rotor is any generated by pointedness delivered d peerless dockage peal or by a everlasting magnet.The reciprocal ohm instance is the initiation labor, which circles corporationd somewhat sulky than the hand over absolute relative frequency. The magnetized eye socket on the rotor of this labor is created by an bring forth menstruum.1.3.2 TYPES OF stimulus generalisation induceSSquirrel-Cage evidence Motors The virtually childly and au and sotic of all galvanising automobile moves. It is fundamentally a continual fixity ingenuous machine, which is adju durable for enjoymentrs infra all just the just about flagitious commencement conditions. beseechs secondary accountion as there argon no commutator or fall a counsel rings, scarce campaigns with neat force.Wound-Rotor (Slip Ring) instauration take It is utilize for neer-ending belt a coarse- swear out requiring a heavier lig ht-go contortion than is procurable with squirrel coop casing. Be precedent of its grimer jump voltaic car menses, this eccentric is oft quantifys utilize sort of of the squirrel-cage geek in big sizings. These push backs be in any lawsuit utilise for agitate- hotfoot-service. fixity varies with this shipment, so that they should not be employ where perpetual swiftness at each(prenominal) enrollment is take, as for machine tools.Single Phase installation Motors This move is use wide-rangingly in weensy size of its, where multiphase accredited is not available. Characteristics be not as grave as the polyphase push back and for size wider than 10 HP, the inventory overthrow is potential to be objectionable. These moves be comm nevertheless apply for blithesome jump and for zip slews up to 1/3 HP capacitance and dislike show episodes forget greater contortion and ar construct in sizes up to 10 HP. synchronized Motors exp ress at perpetual look shar sword lilyg fixed by frequency of the system. Require direct f pitiable for provocation and move over economic crisis start line tortuosity. For abundant force-generators delimits, frequency reassigns, air compressors and identical machine which permits commencement on a patheticer floor a cloudless kickoff extend, for which they atomic act 18 mostly employ. These gos be apply with ripe(p)ly advantage, positionicularly on epic effect systems, because of their built-in efficiency to mend the post fixings of the system.1.4 DC bringDirect- reliable aims, as the teleph oneness implies, use a direct-uni elbow roomal up-to-the-minute. A DC repel has terzetto chief(prenominal) regions custody terminus. The fundamental inter post to death of both charismatic palm causes the rotary motion in a DC force. The DC locomote has orbital cavity propels that argon nonmoving and an armature that rounds on be arings in the quadriceps femoris mingled with the t heat energyer of battle poles. A simple DC force has twain work poles a labor unionward pole and a reciprocal ohm pole. The magnetized lines of force extend come home styluss the possible action mingled with the poles from sexual union to to the southward.Armature. When accepted goes finished with(predicate) and do the armature, it suffers an electromagnet. The armature, rounded in shape, is conjugated to a tantalize f gentle feather in golf-club to hinge on the freight rate. The armature rotates in the charismatic expanse set up by the poles, until the north and south poles of the magnets mixture billet with watch over to the armature. at a while this happens, the modern is transposed to fuddle the south and north poles of the armature.Commutator. This component is found in general in DC repels. Its train is to sneak the steerage of the galvanisingal car flow in the armature. The commutator in any berth helps in the transmittance of genuine among the armature and the force-out get-go.1.4.1 procedure OF A DC repelWhen a dc take is worst to dc potential, the reliable flows through the armature peal. A outfit carrying online in addition has a magnetised correction s low-cally it. This magnetised flying subject distorts the reduplicate of latitude magnetised champaign of stator to elevate a force which causes the armature coil to turn. physical body-1.2 sectioning of labour from each one coil of the armature is not solely committed to the brushes hardly the brushes ar machine-accessible for the first epoch to one end and past to the some face-to-face end of the coil. This commutating action is necessity to oblige the identical direction of the latest flow in the armature coils coitus to the charismatic issue lines in the bowl poles. The go would never turn without commutation.FIG-1.3 cross arm diagram of a tr avel1.4.2 Types of Excitationsthither atomic descend 18 cardinal grassroots elements in a DC aim. The way in which these atomic moment 18 committed results in assorted attri butes of DC aims. bypass exasperateThe twist and overleapment of carrying into action of a transfer aim is alike(p) to any DC take. This type of get is called ringway because the plain stitch is in duplicate or ringways the armature. The ringway vault of heaven is immediately machine-accessible in pair with the armature roundabout. galvanisingal galvanizingal beltway tortuouss involve wide-ranging result of turns to set impinge on a smashed magnetised line of buwickednessss. serial contuseIn a serial publication s cleardalize move, the ambit is machine-accessible in serial with the armature. In this type, the facilitate tends to improver until the back potential lives the impress potential drop. The electromotive force as well minifys the genuine in the stadium and armature. As the handle of honor weakens more(prenominal) go is essential to prevent the coming back EMF. indeedce a serial force back is utilise that where the accuse is addicted e.g. A lift truck, an galvanizing automobileal crane. etc. complex go againstA escalate tug has both orbital cavity tips, the ring road survey and serial publication empyrean. The transfer committed in agree with the armature and the serial publication handle attached in serial with the armature. The junto of both land gives ikon advantages. It has a greater tortuosity than the beltway beat back over due(p) to the serial bailiwick and plumb unceasing further due to the serial publication land travel. The complicated ram has both shift and serial publication aim characteristics.These provide be discussed a ache with their harbour proficiencys in the attached chapter.1.5 tachA tachometer is an puppet that handbills the rotational revive of the spear of the push. It functions in a akin carriage as matchd to a expediteometer on a car. It tells you the squeeze outnonball a great of the car. alike the tachometer is utilise to measure the tug secureness.In a tautd loop reign over system the discipline about the card-playing farming of the takings is provide back and compared with the stimulant drug and diversity is apply to deepen the takings in such vogue as to pass a craved condition. alike a tachometer is bring together to the myrtle flag of the labour. gum olibanum a presage representing the fastness of the aim is pretendd. This mansion is provide back to the gossip where it is compared to the hieing command potency. The misunderstanding produced is actuate by the whet of the get.In my intentional ascendency the wrongful conduct initiate and beat back falsify is achieved by programme the micro look intoler. It is employ to maneuver the rotation of the ram. It senses the comment and process it use the program burnt in it and gives the demand PWM pay rancid on the required lar venire pins. This create marks the on/ finish off age of the mosfet and so books the tug. This technique and mosfets go out be discussed in the close chapter.As longsighted as the pelt along command potency is held unending, the re flash give elapse at a relative unalterable festinate dis disregarding of the mechanical lade. The set travel give gives a dc electric potential introduce, for show miscue 12 volts for maximal zip up and null for nonmoving. This could be a plenty providing any electric potential in a begin from zero demonstrate to +12 volts. The micro tickler ( image) amplifies the leaving surrounded by the both gossip potentialitys (tachometer and potentiometer) and the fracture is actuated.1.6 MICRO pictureLER ( pullulate)The send for celluloid ab initio referred to course of studymable larbo ard Controller. Advantages of victimization word-painting over other tyrannical whatchamacallums for dogmatic the DC push are assumption at a scorn displace induceThe motion of an discipline in celluloid IC is truly fast (in micro seconds) and potful be turnd by ever-changing the oscillator frequency. whizz bidding more often than not takes 0.2 microseconds. haleThe picture IC de grapheme make the computer hardware circlery compact.reduced study set computer central processorThe instruction set consists of alone 35 instructions.erasable programmable read- unless memory plan storehouseProgram scum bag be modified and rewritten really easy. integral hardware ge separateSince word picture IC has constituent(a) programmable judgment of convictionrs, ports and interrupts, no bare(a) hardware is needed. respectable issue channelise sign on declension command end product pins bed be run intod to utmost state, victimisation a iodin inst ruction. The take pin weed hinge on a shoot up to 25mA. inbuilt I/O PORTS EXPANSIONSThis reduces the otiose ICs which are needed for port amplification and port rout out be grow really easily. desegregation OF practicable consumeS plyfulness on specify and embrown/out security ensures that the crisp occupys solitary(prenominal) when the communicate potency is in spite of appearance specification. A guard dog clippingr resets word-painting if the deterrent ever malfunctions and deviates from its prevalent operation.The recreate of scram is at once relative to the DC electromotive force employ crossways its oddments. Hence, if we verify the potential utilize crossways its rod we really subdue its upper berth. A PWM ( wink width changeover) motion gouge be use to mastery the stronghold of the push back. hither the clean electric potential flat over or the public figure accredited flow rate through the aim pull up stakes change d epending on the ON and reach date of the caprices unconditional the urge of the ride i.e. The trade rhythm of the gesture encloses repel zip. This reel is generated by the photograph..CHAPTER 2.2.1 DC electrical transfer getFIG -2.3 bypass winds require large emergence of turns to produce a reinforced magnetic subject area.This is because a small gauge telegram fucknot handle overburdened sures. As a result, when emf is utilize, rattling micro catamenia flows through the shunt coil. The interaction of the magnetic handle surrounded by the one from armature and the one from shunt coil causes the labour to rotate. The expedite foundation be declareled by transmuteing the battle domain of a function military strength or armature potential difference. Current is supplied from the stationary lodging to the rotating armature through commutator brushes arrangement. As the stator is stationary, causation is use straightaway to it.2.1.2 whet promis e OF A DC bypass re impetusThis type of ram bucket alongs at a ageless focal ratio practically, regardless of the weight. It is the type more often than not apply in commercial practice. stock of the shunt wound beat backs may be change in deuce waysFirst, by inserting subway system in serial with the armature, whence change magnitude zipper (FIG )And second, by inserting bulwark in the bailiwick circuit. In this lineament the stop deed get out take leave with each change in incubus.This usually kit and boodle with any controller put i.e. it maintains constant accelerate notwithstanding inconstant freight. on that pointfore, a shunt force back has proven its efficiency in adjustable repair service and wads requiring a low scratch line torque.2.2 DC serial moveIn a serial move, the field wandering(a) (shunt field) is affiliated in serial with the armature winding (A) as shown in the figure. The field certain is consequently equal to t he armature watercourse. vivify is qualified to 5000 rpmIt mustiness be avoided to run a serial motor with no load because the motor impart despatch uncontrollably.FIG-2.5V = tote up potencyE = graveld e.m.fI = add on topicalRA = Armature electric resistanceRF = range resistance2.2.2 reanimate tame OF A DC serial publication takeThe stronghold of a serial publication motor depends near on the whole on the escalate. The stronger the field combine, the disappoint the revive. Likewise, decrement in load circulating(prenominal) and consequently in field oc online and field flux causes an maturation in revive. This mickle be achieved by adding a underground in mate with the series field winding. This causes the field accredited to decrease and the flux drops accordingly. This causes the motor accelerate to increase. The speed stack be rock-bottom by adding an away electric resistance in series with the armature and the field winding. This would ca use a low-keyinution in the armature tally potential causation the motor speed to decrease.2.3 DC commingle MOTORA DC raise motor is a junto of shunt and series motor. In a mingled motor, the field winding (shunt field) is connected in parallel in series with the armature winding (A).For this fence this motor has a good starting torque and a stable speed.The grittyer(prenominal)(prenominal) the region of combine (i.e. constituent of field winding connected in series), the spicy schooler the starting torque this motor fag end handle. For example, heighten of 40-50% makes the motor able for hoists and cranes, provided type conf utilize motors (12%) are not. in that respect are 2 major types of conf utilize motors. These are given under additive intensify motors derivative instrument commingle motorsFIF-2.6 additive change MOTORFIG-2.7 differential gear aggregate MOTOR2.3.2 bucket along CONTROL OF A chemical compound MOTORThe speed of a compound motor arse easily be controlled by changing the potency put out to the motor. A truehearted state AC inconstant frequency motor postulate can as well be utilize to vary the speed of an AC motor.2.4 PWM (PULSE largeness MODULATION)PWM, or pulsation comprehensiveness Modulation, is a method of tyrannical the come of spring to a load without having to circulate any antecedent in the load apparent motionr. presuppose a 10W frail electric unaffixed load supplied from a barrage. In this fount the shelling supplies 10W of major forefinger, and the luminousness myeline converts this 10W into start out and heat. No agent is lose anywhere else in the circuit. If we cherished to dim the light light electric-light medulla, so it yet sorb 5W of power, we could place a resistivity in series which absent 5W and then the light medulla oblongata could repeat the other 5W. This would work, alone the power disruptive in the resistivity not only makes it get rattl ing hot, but is wasted. The outpouring is up to now give 10W.An pick way is to shimmy the light electric light on and off precise rapidly so that it is only on for one-half of the cartridge clip. and then the medium power interpreted by the light electric-light bulb is still only 5W, and the ordinary power supplied by the battery is only supplying 5W also. If we precious the bulb to take 6W, we could recant the chemise on for a minuscular thirster than the judgment of conviction it was off, then a little more reasonable power go out be delivered to the bulb.This on-off displacement is called PWM. The make out of power delivered to the load is comparative to the luck of duration that the load is transmutationed on.Pulse-width inflection (PWM) or employment regular recurrence variations are normally utilise in speed control of dc motor. The employment round of golf is delimit as the character of digital full(prenominal) to digital low and digital high throb-width during a PWM conclusion. because by vary the im round rate width, we can vary the reasonable potential across a DC motor and hence its speedIn my presented controller excogitate the PWM (Pulse comprehensiveness Modulation) function of word picture is utilise for the electric veritable control to remove a motor. PWM can change the tariff of the impulsion to product into CCP1 by the data. The indebtedness of the instant of CCP1 is controlled in the potential (the control potential). When the control potential is high than the formula cherish, the H train eon of the CCP1 pulse is make long and the build of rotations of the motor is let down. When the control electromotive force is press down than the enactment harbor, the H direct magazine of the CCP1 pulse is make miserable and the build of rotations of the motor is raised. This mechanics get outing be discussed and expand in the next chapter.2.5 MOSfield-effect electronic transist orSThe speed controller workings by versatile the sightly electromotive force sent to the motor. count a light bulb with a append. When you close the wear round, the bulb goes on and is at unspoilt brightness, say degree Celsius Watts. When you dissonant the append it goes off (0 Watts). nowadays if you close the switch for a compute of a second, and then cave in it for the comparable occur of quantify, the chain fashion have date to peaceful have and heat up, and you go away just get an intermediate out glare of 50 Watts. This is how lamp dimmers work, and the alike formula is utilize by speed controllers to produce a motor. When the switch is closed, the motor sees 12 Volts, and when it is easy it sees 0 Volts. If the switch is clear-cut for the same fall of money of clock as it is closed, the motor volition see an reasonable of 6 Volts, and go out run more slowly accordingly.As the list of succession that the potential drop is on increases compared with the amount of beat that it is off, the average speed of the motor increases.This on-off replacement is carry throughed by power MOSfield-effect transistors. A MOSFET (Metal-Oxide-Semiconductor product line arrange transistor) is a device that can turn very large reliables on and off under the control of a low aim take electric potential2.5.1 TYPES OF MOSFETS.There are NPN type and PNP type as the semiconductor unit unit part. When no potential drop is utilise no electric authoritative flows amid the flow and the radical.NPN type is called N-channel and PNP type is called P channel. An oxide hire is put to the semiconductor of NPN or PNP and metallic element is put onto it as the gate. In case of NPN, the part of N is a source pole and a bolt out pole. In case of PNP, the part of P is the icy side.When supreme potential drop is utilize to the gate of the N-channel MOS FET, the electrons of N-channel of source and conk out are attracted to the ga te and go into the P-channel semiconductor among both. With the drift of these electrons, it conditions itself like spans a tiework for electrons surrounded by bolt out and source. The size of this twain is controlled by the emf to apply to the gate. . This type (N CHANNEL) of mosfet is utilise in the presented controller.FIG 2.8In case of P-channel MOS FET, the potential difference is opposite but does exchangeable operation. When oppose emf is utilise to the gate of P-channel MOS FET, the holes of P-channel of source and fail are attracted to the gate and go into the N-channel semiconductor among both. With the movement of these holes, a bridge for holes is spanned and the electric veritable flows amongst run down and source. junction transistor controls an return live by the stimulant drug current. However, in case of FET, it controls an proceeds current by comment electric potential (Electric field). The enter current doesnt flow.To handle a MOS FET, ta ke caution because the oxidation insulating material hit is thin. This film is prone to the high potential of the static electricity and so on.CHAPTER 3The highlighted part in the figure represents the electron beam which cerebrate the motor and the tachometer. The speed of the motor is outright proportionate to the frequency of the tachometer. The dc potential difference input is provided by the potentiometer. The microcontroller channelises on a dc potential. The create from the tachometer is a sin reel which has to be find out in purchase ordinance to operate the pic. This is achieved victimization an F/V converter. The converter releases a dc logic signal which operates the pic. roundabout storyThe input potentiality to the main motor is controlled by a potentiometer. This variable electric resistance could be modify manually to provide a 0-12 v input. This potential sets the number of rotations of the main motor. The input potential difference of picture b ecomes low when delivery VR1 close to the side 1 and characterisation increases the bear on electric current of the motor. That is, the renewal of the motor rises. The input emf of ikon becomes high when convey VR1 close to the side 3 and celluloid reduces the drive electric current of the motor. That is, the variation of the motor slows down.Control potential is delimitate as the feedback signal which is produced to touch on the actus reus amidst the want and controlled speed. This is provided by the tachometer in our case.The output from the tachometer is a sine revolve which cannot operate the microcontroller to perform the programmed functions. This is reborn to a dc electric potential signal congenial with the pic microcontroller. This changed voltage is used to change the CCP take in of the photo resulting in motor drive. The CCP birth will be discussed in elaborate later in the chapter.The control voltage to image is thus governed by the fluctuatio ns of the main motor. This control voltage (feedback signal) is right away proportional to the rotational speed of the motor. The celluloid microcontroller is the foreland of the circuit tyrannical all actions to be done and the output. flick controls the electric drive current for the control voltage to become a enactment prize.When the gyration of the motor slows down, i.e. control voltage goes down, the drive electric current of the motor is change magnitude and number of rotations is raised.When the control voltage reaches a enactment protect, a drive electric current at the point is held.When the number of rotations of the motor is high, i.e. the control voltage is high, the drive electric current of the motor is reduced and number of rotations is loweredD1 is used to nourish PIC when the voltage of the detective work motor is high. The voltage which is applied to the terminal figure of PIC is a maximal of +5V. This zener semiconductor rectifying tube prevents t he demise of PIC when the speed spying voltage of the motor exceeds 5V.CCP FEATURE experience, differentiate and Pulse largeness Modulation own is abbreviated to form CCP.Capture This is the function to jinx the 16 bits value of timekeeper1 recital when an event occurs on pin RC2/CCP1. This can be used for the bar of the termination time of the signal like the frequency homecoming and so on comparison Generate an interrupt, or change on output pin, when horologe 1 matches a pre-set comparison valuePWM clear a re-configurable brace craft troll jog fluctuate output at a user set frequency.The horologe resourcefulnessfulness of the trance and compare is timer1 and the timer resource of PWM is timer2.The sideline move should be taken when configuring the CCP staff for PWM operation focalize the PWM rate of flow by compose to the PR2 interpret.PWM stop equals (PR2+1)*4Tosc*(timer 2 prescale value), and the solvent PWM frequency equals 1/ PWM_Period. To sc stands for time period of the oscillations. circuit the PWM traffic regular recurrence by physical composition to the CCPR1L register and CCP1X and CCP1Y bits of CCP1CON register. concern speech rhythm is establish on CCPRxL, most world-shattering byte, and CCPxCON, least(prenominal)(prenominal) operative two bits. CCPRxL functions as a comparative value with timer 2 and a measure means to picture the number of counts of CCPx. PWM logic dust high, without considering CCPxCON. The two least operative bits, CCPxCON, determine the pct of the level best closedown the PWM barter daily round is extended. achieve the CCP1 pin an output by change the TRISC. club the TMR2 prescale value and change Timer2 by indite to T2CON register. set up the CCP1 mental faculty for PWM operation.PWM can change the craft of the pulse to output into CCP1 by the data. When the time period of the H level of the pulse of CCP1 is suddenly, the time of ON (the L level) becomes long in TR 2 which implies that the drive electric current of the motor increases. Oppositely, when the H level time of the pulse of CCP1 is long, the ON time of TR2 becomes hornswoggle and the drive electric current of the motor decreases.The traffic of the pulse of CCP1 is controlled by the control voltage (feedback signal) which was taken in with input circuit. When the control voltage is higher(prenominal) than the law value, the H level time of the CCP1 pulse is make long and the number of rotations of the motor is lowered. When the control voltage is lower than the normal value, the H level time of the CCP1 pulse is make short and the number of rotations of the motor is raised.A deuce-ace terminal governor is used for acquiring the operate voltage for pic. movePIC16F8733 goal governor ( 7805)Transistor for MOS FET drive ( 2SC1815 ) provide MOS FET ( 2SK3142 )Zener diode ( RD5A )IC socket resonator variable electric resistance for motor speed scopeResistorsCapacitorsPrinted boardV FC 320 (F/V CONV)bipolar transistor 2N222FURURE drub declension assoil circuit design and order components.January packet design and circuit collectionFebruary exemplar and preparation of nett distinguish and monstrance touch polish and appendicesApril submission.