Ntchito yamadzimadzi amadzimadzi amawonetsa mphamvu zamagetsi makamaka kutembenuza mphamvu ya mains 220V kukhala mafunde osiyanasiyana okhazikika omwe amafunikira kuti agwiritse ntchito mawonekedwe amadzimadzi amadzimadzi, komanso kupereka voteji yoyendetsera mabwalo osiyanasiyana, mabwalo omveka, mapanelo owongolera, etc. . mu chiwonetsero cha kristalo chamadzimadzi, ndi kukhazikika kwake kogwira ntchito Imakhudza mwachindunji ngati LCD monitor ingagwire ntchito bwino.
1. Kapangidwe ka madzi kristalo kusonyeza dera magetsi
Mphamvu yamagetsi yamadzimadzi yamadzimadzi imapanga 5V, 12V yogwira ntchito. Pakati pawo, voteji 5V makamaka amapereka voteji ntchito kwa logic dera gulu lalikulu ndi nyali chizindikiro pa gulu ntchito; voteji ya 12V makamaka imapereka mphamvu yogwira ntchito pa bolodi lamagetsi apamwamba ndi bolodi yoyendetsa.
Dongosolo lamagetsi limapangidwa makamaka ndi fyuluta, bridge rectifier filter circuit, main switch circuit, switching transformer, rectifier filter circuit, protection circuit, soft start circuit, PWM controller ndi zina zotero.
Pakati pawo, udindo wa AC fyuluta dera ndi kuthetsa kusokoneza mkulu pafupipafupi mu mains (mzere fyuluta wozungulira kawirikawiri amapangidwa resistors, capacitors ndi inductors); Udindo wa sefa yowongolera mlatho ndikusinthira 220V AC kukhala 310V DC; kusintha dera Ntchito ya rectification fyuluta dera ndi kutembenuza mphamvu DC pafupifupi 310V kudzera kusintha chubu ndi kusintha thiransifoma mu pulse voltages osiyanasiyana amplitudes; ntchito ya rectification fyuluta dera ndi kutembenuza pulse voltage linanena bungwe thiransifoma mu voteji 5V zofunika ndi katundu pambuyo kukonza ndi kusefa ndi 12V; Ntchito yozungulira chitetezo cha overvoltage ndikupewa kuwonongeka kwa chubu chosinthira kapena magetsi osinthika chifukwa cha katundu wovuta kapena zifukwa zina; ntchito ya woyang'anira PWM ndikuwongolera kusintha kwa chubu chosinthira ndikuwongolera dera molingana ndi mphamvu yamagetsi yamagetsi yachitetezo.
Chachiwiri, mfundo ntchito ya madzi galasi kusonyeza magetsi dera
Dongosolo lamagetsi lamagetsi amadzimadzi amadzimadzi nthawi zambiri limatenga njira yosinthira. Dongosolo loperekera magetsili limasintha voteji ya AC 220V kukhala voteji ya DC kudzera pagawo lowongolera ndi kusefa, kenako imadulidwa ndi chubu chosinthira ndikutsitsidwa ndi chosinthira chamtundu wapamwamba kwambiri kuti mupeze voteji yamakona amakona apamwamba kwambiri. Pambuyo pokonzanso ndikusefa, magetsi a DC omwe amafunikira gawo lililonse la LCD amatuluka.
Zotsatirazi zimatenga chiwonetsero cha kristalo chamadzi cha AOCLM729 monga chitsanzo chofotokozera mfundo yogwirira ntchito yamagetsi amagetsi amadzimadzi. Dongosolo lamagetsi la AOCLM729 liquid crystal display makamaka limapangidwa ndi AC filter circuit, bridge rectifier circuit, soft start circuit, main switch circuit, rectifier filter circuit, overvoltage protection circuit ndi zina zotero.
Chithunzi chowonekera cha board circuit power:
Chithunzi chojambula chamagetsi amagetsi:
- Zosefera za AC
Ntchito ya sefa ya AC ndikusefa phokoso lomwe limayambitsidwa ndi mzere wolowera wa AC ndikuletsa phokoso la mayankho lomwe limapangidwa mkati mwamagetsi.
Phokoso mkati mwa magetsi makamaka limaphatikizapo phokoso lamtundu wamba komanso phokoso labwinobwino. Pamagetsi agawo limodzi, pali mawaya amagetsi a 2 AC ndi waya wapansi umodzi kumbali yolowera. Phokoso lopangidwa pakati pa mizere iwiri yamagetsi ya AC ndi waya pansi pa mbali yolowera mphamvu ndi phokoso wamba; phokoso lopangidwa pakati pa mizere iwiri yamagetsi ya AC ndi phokoso labwinobwino. Dera losefera la AC limagwiritsidwa ntchito makamaka kusefa mitundu iwiri ya phokoso. Kuphatikiza apo, imagwiranso ntchito ngati chitetezo chamagetsi ozungulira komanso chitetezo cha overvoltage. Pakati pawo, fuseyi imagwiritsidwa ntchito poteteza ma overcurrent, ndipo varistor imagwiritsidwa ntchito poteteza voteji overvoltage. Chithunzi chomwe chili pansipa ndi chojambula cha sefa ya AC.
Pachithunzichi, ma inductors L901, L902, ndi capacitors C904, C903, C902, ndi C901 amapanga fyuluta ya EMI. Inductors L901 ndi L902 amagwiritsidwa ntchito kusefa otsika pafupipafupi phokoso wamba; C901 ndi C902 amagwiritsidwa ntchito kusefa otsika pafupipafupi phokoso wamba; C903 ndi C904 amagwiritsidwa ntchito kusefa pafupipafupi phokoso wamba ndi phokoso wamba (high frequency electromagnetic interference); Zoletsa zapano R901 ndi R902 zimagwiritsidwa ntchito kutulutsa capacitor pomwe pulagi yamagetsi imatulutsidwa; Inshuwaransi F901 imagwiritsidwa ntchito poteteza mopitilira muyeso, ndipo varistor NR901 imagwiritsidwa ntchito poteteza magetsi ochulukirapo.
Pamene pulagi yamagetsi yamadzimadzi amadzimadzi imayikidwa muzitsulo zamagetsi, 220V AC imadutsa fusesi F901 ndi varistor NR901 kuti iteteze kukhudzidwa, ndikudutsa dera lopangidwa ndi capacitors C901, C902, C903, C904, resistors R901, R902, ndi inductors L901, L902. Lowetsani dera lokonzanso mlatho pambuyo pa anti-interference circuit.
2. Mlatho rectifier fyuluta dera
Ntchito ya sefa yosinthira mlatho ndikusinthira 220V AC kukhala voteji ya DC pambuyo pokonzanso mafunde athunthu, kenako ndikusintha magetsi kukhala ma voliyumu a mains kawiri mutatha kusefa.
Zosefera zowongolera mlatho zimapangidwa makamaka ndi chowongolera mlatho DB901 ndi fyuluta capacitor C905..
Pachithunzichi, chowongolera mlatho chimapangidwa ndi ma diode 4 okonzanso, ndipo capacitor ya fyuluta ndi capacitor 400V. Ma mains a 220V AC akasefedwa, amalowa mlatho wokonzanso. Pambuyo pokonzanso mlatho kukonzanso mafunde athunthu pamakina a AC, imakhala magetsi a DC. Kenako magetsi a DC amasinthidwa kukhala magetsi a 310V DC kudzera pa fyuluta capacitor C905.
3. Yofewa chiyambi dera
Ntchito ya dera loyambira lofewa ndikuletsa mphamvu yanthawi yomweyo pa capacitor kuti zitsimikizire kuti ntchito yabwino komanso yodalirika yamagetsi osinthira. Popeza magetsi oyambira pa capacitor ndi zero panthawi yomwe gawo lolowera limayatsidwa, mphamvu yayikulu yolowera nthawi yomweyo imapangidwa, ndipo izi nthawi zambiri zimapangitsa kuti fusesi yolowera iphulike, kotero kuti dera loyambira mofewa liyenera khalani okonzeka. Dera loyambira lofewa limapangidwa makamaka ndi zopinga zoyambira, ma diode owongolera, ndi ma capacitor osefera. Monga momwe chithunzichi chikusonyezera ndi chithunzi chojambula cha dera loyambira lofewa.
Pachithunzichi, zotsutsa R906 ndi R907 ndizofanana ndi 1MΩ. Popeza otsutsawa ali ndi mtengo waukulu wokana, ntchito yawo ndi yochepa kwambiri. Mphamvu yosinthira ikangoyambika, mphamvu yoyambira yomwe ikufunika ndi SG6841 imawonjezedwa kumalo olowera (pini 3) ya SG6841 itatsitsidwa ndi 300V DC high voltage kudzera pa resistors R906 ndi R907 kuti izindikire kuyambika kofewa. . Chubu chosinthira chikasintha kukhala ntchito yabwinobwino, magetsi othamanga kwambiri omwe amakhazikitsidwa pa switching thiransifoma amakonzedwa ndikusefedwa ndi rectifier diode D902 ndi fyuluta capacitor C907, kenako imakhala mphamvu yogwira ntchito ya SG6841 chip, ndikuyamba- up process yatha.
4. chachikulu lophimba dera
Ntchito ya chigawo chachikulu chosinthira ndikupeza mphamvu yamagetsi yamakona amakona apamwamba kwambiri kudzera pakusintha machubu ndikusintha ma transfoma apamwamba kwambiri.
Dera lalikulu losinthira limapangidwa makamaka ndi chubu chosinthira, chowongolera cha PWM, chosinthira thiransifoma, dera lodzitchinjiriza, chitetezo chamagetsi apamwamba ndi zina zotero.
Pachithunzichi, SG6841 ndi wowongolera wa PWM, womwe ndiye maziko amagetsi osinthira. Ikhoza kupanga chizindikiro choyendetsa galimoto ndi mafupipafupi okhazikika komanso kusinthasintha kwa pulse, ndikuwongolera malo otsekedwa ndi chubu chosinthira, potero kusintha mphamvu yamagetsi kuti ikwaniritse cholinga cha kukhazikika kwamagetsi. . Q903 ndi chubu chosinthira, T901 ndi chosinthira chosinthira, ndipo dera lopangidwa ndi ma voltage regulator chubu ZD901, resistor R911, transistors Q902 ndi Q901, ndi resistor R901 ndi dera lodzitchinjiriza.
PWM ikayamba kugwira ntchito, pini ya 8th ya SG6841 imatulutsa mafunde amtundu wamakona (nthawi zambiri ma frequency a pulse ndi 58.5kHz, ndipo ntchito yozungulira ndi 11.4%). Kugunda kumawongolera chubu losinthira Q903 kuti lizisintha molingana ndi kuchuluka kwake. Pamene chubu yosinthira Q903 imayatsidwa / kuzimitsa mosalekeza kuti ipangitse kudzisangalatsa kosangalatsa, thiransifoma T901 imayamba kugwira ntchito ndikupanga magetsi ozungulira.
Pamene linanena bungwe terminal ya pini 8 wa SG6841 ndi mkulu mlingo, kusintha chubu Q903 anatembenukira, ndiyeno koyilo chachikulu cha kusintha thiransifoma T901 ali panopa ikuyenda mwa izo, amene amapanga voteji zabwino ndi zoipa; nthawi yomweyo, yachiwiri ya thiransifoma imapanga ma voltages abwino ndi oipa. Panthawiyi, diode D910 yachiwiri imadulidwa, ndipo siteji iyi ndi malo osungirako mphamvu; pamene chotuluka cha pini 8 cha SG6841 chili pamlingo wochepa, chubu chosinthira Q903 chimadulidwa, ndipo chapano pa koyilo yoyamba ya chosinthira T901 chimasintha nthawi yomweyo. ndi 0, mphamvu ya electromotive ya pulayimale ndi yotsika yabwino komanso yotsika, ndipo mphamvu ya electromotive yapamwamba ndi yabwino komanso yotsika imapangidwira pachiwiri. Panthawi imeneyi diode D910 anatembenukira ndi kuyamba linanena bungwe voteji.
(1) Chitetezo chambiri
Mfundo yogwira ntchito ya overcurrent chitetezo dera ndi motere.
Pambuyo poyatsa chubu Q903, magetsi akuyenda kuchokera kukheni kupita kugwero la chubu Q903, ndipo magetsi adzapangidwa pa R917. Resistor R917 ndi chodziwikiratu chodziwikiratu, ndipo voteji yomwe imapangidwa ndi iyo imawonjezedwa mwachindunji ku malo olowera osalowetsamo omwe amafananiza ndi chipangizo cha PWM chowongolera SG6841 chip (chomwe ndi pini 6), bola mphamvu ikadutsa 1V. ipanga chowongolera cha PWM SG6841 mkati Chigawo chachitetezo chapano chimayamba, kotero kuti pini ya 8 imasiya kutulutsa mafunde amphamvu, ndi chubu chosinthira ndikusintha thiransifoma kusiya kugwira ntchito kuti azindikire chitetezo chapano.
(2) High voltage chitetezo dera
Mfundo yogwirira ntchito yachitetezo chamagetsi apamwamba ndi motere.
Magetsi a gridi akakwera kupitilira mtengo wokwera, voteji yotulutsa mawu amtundu wa transformer nawonso iwonjezeka. Mpweya wothamanga udzapitirira 20V, panthawiyi chubu chowongolera magetsi ZD901 chasweka, ndipo kutsika kwamagetsi kumachitika pa resistor R911. Pamene dontho la voteji ndi 0.6V, transistor Q902 imayatsidwa, ndiyeno m'munsi mwa transistor Q901 imakhala yapamwamba, kotero kuti transistor Q901 nayonso imatsegulidwa. Nthawi yomweyo, diode D903 imayatsidwanso, ndikupangitsa kuti pini ya 4 ya chipangizo chowongolera cha PWM SG6841 ikhazikike, zomwe zimapangitsa kuti pakhale mawonekedwe afupipafupi, zomwe zimapangitsa woyang'anira PWM SG6841 kuzimitsa kutulutsa kwamphamvu.
Kuphatikiza apo, transistor Q902 ikayatsidwa, voliyumu ya 15V ya pini 7 ya PWM controller SG6841 imakhazikika mwachindunji kudzera pa resistor R909 ndi transistor Q901. Mwanjira imeneyi, voteji yamagetsi opangira magetsi a PWM controller SG6841 chip imakhala 0, wowongolera wa PWM amasiya kutulutsa mafunde amphamvu, ndipo chubu chosinthira ndikusintha thiransifoma kuyimitsa kugwira ntchito kuti akwaniritse chitetezo champhamvu kwambiri.
5. Rectifier fyuluta dera
Ntchito ya rectification fyuluta yozungulira ndikukonza ndikusefa voteji yotulutsa thiransifoma kuti mupeze voteji yokhazikika ya DC. Chifukwa cha kutayikira kwa thiransifoma ndi spike chifukwa cha kubwezeredwa m'mbuyo kwa diode yotulutsa, zonse zimapanga kusokoneza kwamagetsi. Chifukwa chake, kuti mupeze ma voteji a 5V ndi 12V, mphamvu yamagetsi yosinthira masinthidwe iyenera kukonzedwa ndikusefedwa.
Zosefera zosinthira zimapangidwa makamaka ndi ma diode, zopinga zosefera, zosefera ma capacitors, zosefera zosefera, ndi zina.
Pachithunzichi, RC fyuluta yozungulira (resistor R920 ndi capacitor C920, resistor R922 ndi capacitor C921) yolumikizidwa molingana ndi diode D910 ndi D912 kumapeto kwachiwiri kwa switching thiransifoma T901 imagwiritsidwa ntchito kuyamwa magetsi opangira magetsi opangidwa pamagetsi. diode D910 ndi D912.
Fyuluta ya LC yopangidwa ndi diode D910, capacitor C920, resistor R920, inductor L903, capacitors C922 ndi C924 imatha kusefa kusokoneza kwamagetsi kwamagetsi a 12V otulutsa ndi thiransifoma ndikutulutsa voteji yokhazikika ya 12V.
Fyuluta ya LC yopangidwa ndi diode D912, capacitor C921, resistor R921, inductor L904, capacitors C923 ndi C925 imatha kusefa kusokoneza kwamagetsi kwamagetsi a 5V otulutsa thiransifoma ndikutulutsa voteji yokhazikika ya 5V.
6. 12V / 5V olamulira olamulira dera
Popeza magetsi a mains 220V AC amasintha mkati mwamitundu ina, mphamvu ya mains ikakwera, voteji yotulutsa ya thiransifoma mudera lamagetsi nayonso ikwera molingana. Kuti mupeze ma voltages okhazikika a 5V ndi 12V, dera la Regulator.
Dongosolo la 12V/5V voltage regulator limapangidwa makamaka ndi precision voltage regulator (TL431), optocoupler, controller PWM, ndi voltage divider resistor.
Pachiwerengerocho, IC902 ndi optocoupler, IC903 ndi chowongolera voteji molondola, ndipo resistors R924 ndi R926 ndi ma voltage divider resistors.
Magetsi akamagwira ntchito, 12V yotulutsa DC voliyumu imagawidwa ndi resistors R924 ndi R926, ndipo voliyumu imapangidwa pa R926, yomwe imawonjezedwa mwachindunji ku TL431 precision voltage regulator (ku R terminal). Ikhoza kudziwika kuchokera kumagulu otsutsa pa dera Voltage iyi ndi yokwanira kuyatsa TL431. Mwanjira iyi, voteji ya 5V imatha kuyenda kudzera pa optocoupler ndi chowongolera chowongolera chamagetsi. Pamene magetsi akuyenda kudzera mu optocoupler LED, optocoupler IC902 imayamba kugwira ntchito ndikumaliza kuyesa kwamagetsi.
Mphamvu yamagetsi ya 220V AC ikakwera ndipo voteji yotulutsa ikukwera moyenerera, zomwe zikuyenda kudzera pa optocoupler IC902 zidzawonjezekanso moyenerera, ndipo kuwala kwa diode yotulutsa kuwala mkati mwa optocoupler kudzawonjezekanso moyenerera. Kukaniza kwamkati kwa phototransistor kumakhalanso kochepa panthawi imodzi, kotero kuti digiri ya conduction ya phototransistor terminal idzalimbikitsidwanso. Pamene digiri ya conduction ya phototransistor ilimbikitsidwa, voteji ya pini 2 ya PWM yolamulira mphamvu SG6841 chip idzatsika nthawi yomweyo. Popeza votejiyi imawonjezedwa ku inverting inverting ya amplifier yamkati ya SG6841, ntchito yozungulira ya SG6841 imayendetsedwa kuti ichepetse mphamvu yamagetsi. Mwa njira imeneyi, overvoltage linanena bungwe ndemanga kuzungulira aumbike kukwaniritsa ntchito yokhazikika linanena bungwe, ndi linanena bungwe voteji akhoza okhazikika pa kuzungulira 12V ndi 5V linanena bungwe.
lingaliro:
Optocoupler amagwiritsa ntchito kuwala ngati sing'anga kufalitsa ma siginecha amagetsi. Zili ndi zotsatira zabwino zodzipatula pazolowera ndi zotulutsa zamagetsi, motero zimagwiritsidwa ntchito kwambiri m'mabwalo osiyanasiyana. Pakadali pano, yakhala imodzi mwazinthu zosiyanasiyana komanso zogwiritsidwa ntchito kwambiri ndi optoelectronic. Optocoupler nthawi zambiri imakhala ndi magawo atatu: kutulutsa kuwala, kulandira kuwala, ndi kukulitsa ma siginecha. Chizindikiro chamagetsi cholowera chimayendetsa diode yotulutsa kuwala (LED) kuti itulutse kuwala kwa utali wina wake, womwe umalandiridwa ndi chithunzithunzi kuti apange chithunzithunzi, chomwe chimakulitsidwa ndikutuluka. Izi zimamaliza kutembenuka kwamagetsi-mawonekedwe-magetsi, motero kumachita gawo la kulowetsa, kutulutsa, ndi kudzipatula. Popeza kulowetsa ndi kutulutsa kwa optocoupler kumakhala kosiyana kwa wina ndi mzake, ndipo kufalitsa kwa chizindikiro cha magetsi kumakhala ndi makhalidwe a unidirectionality, kumakhala ndi mphamvu zabwino zamagetsi zamagetsi komanso mphamvu zotsutsana ndi kusokoneza. Ndipo chifukwa cholowera kumapeto kwa optocoupler ndi chinthu chotsika kwambiri chomwe chimagwira ntchito pakalipano, chimakhala ndi mphamvu yokana kukana. Chifukwa chake, imatha kusintha kwambiri chiŵerengero cha ma sign-to-noise ngati chinthu chodzipatula pakufalitsa kwanthawi yayitali. Monga chipangizo cholumikizira chizindikiro chodzipatula pamakompyuta pamakompyuta komanso kuwongolera nthawi yeniyeni, zitha kukulitsa kudalirika kwa ntchito zamakompyuta.
7. overvoltage chitetezo dera
Ntchito ya overvoltage chitetezo dera ndi kuzindikira linanena bungwe voteji wa linanena bungwe dera. Mphamvu yotulutsa thiransifoma ikakwera modabwitsa, kutulutsa kwamphamvu kumazimitsidwa ndi wowongolera wa PWM kuti akwaniritse cholinga choteteza dera.
Dera lodzitchinjiriza la overvoltage limapangidwa makamaka ndi chowongolera cha PWM, optocoupler, ndi chubu chowongolera ma voltage. Monga momwe tawonera pamwambapa, chubu chowongolera ma voltage ZD902 kapena ZD903 pazithunzi zamadongosolo ozungulira amagwiritsidwa ntchito kuti azindikire mphamvu yamagetsi.
Mphamvu yachiwiri ya chosinthira chosinthira ikakwera modabwitsa, chubu chowongolera ma voltage ZD902 kapena ZD903 chidzasweka, zomwe zipangitsa kuti kuwala kwa chubu chotulutsa kuwala mkati mwa optocoupler kuchuluke mosadziwika bwino, ndikupangitsa pini yachiwiri ya wolamulira wa PWM. kudutsa optocoupler. Phototransistor mkati mwa chipangizocho imakhazikitsidwa, wolamulira wa PWM amadula mofulumira kutulutsa kwa pini 8, ndi chubu chosinthira ndi kusintha kwa thiransifoma kusiya kugwira ntchito nthawi yomweyo kuti akwaniritse cholinga choteteza dera.
Nthawi yotumiza: Oct-07-2023