Asynchronous electric motors tam sim no siv heev. Lawv muaj qee qhov zoo vim tias lawv tau dhau los ua neeg nyiam. Txhawm rau txuas cov motors muaj zog rau cov khoom siv hluav taws xob, "hnub qub", "daim duab peb sab" schemes yog siv. Fais motors ua hauj lwm ntawm xws li schemes muaj lawv tus kheej zoo thiab tsis zoo. Lawv lawv tus kheej yog qhov txawv ntawm kev ntseeg siab hauv kev ua haujlwm, muaj peev xwm kom tau txais lub zog siab, nrog rau qhov ntsuas kev ua haujlwm siab.
motor txuas
Raws li kev xyaum qhia, muaj ob lub tswv yim zoo - "hnub qub", "daim duab peb sab". Hluav taws xob motors txuas rau ntawm ib qho ntawm lawv. Nws tseem tuaj yeem hloov "hnub qub" rau "daim duab peb sab", piv txwv li.
Ntawm qhov zoo ntawm asynchronous motors, cov hauv qab no sawv tawm:
- hloov tauwindings thaum ua haujlwm;
- rov qab ntawm lub tshuab hluav taws xob winding;
- tus nqi qis ntawm cov cuab yeej cuam tshuam nrog lwm tus;
- siab tiv thaiv kev puas tsuaj.
Lub ntsiab feature uas qhia tag nrho cov asynchronous electric motors yog qhov yooj yim ntawm kev tsim. Txawm li cas los xij, nrog rau tag nrho nws qhov zoo, muaj qee qhov tsis zoo uas tshwm sim thaum lub sijhawm ua haujlwm:
- Tsis muaj peev xwm tswj rotor ceev yam tsis muaj hluav taws xob nkim.
- Thaum lub load nce, lub torque txo.
- siab pib tam sim no.
Kev piav qhia kev sib txuas
Lub "hnub qub" thiab "delta" circuits rau lub tshuab hluav taws xob muaj qee qhov sib txawv hauv kev sib txuas. "Lub hnub qub" txhais tau hais tias qhov kawg ntawm stator winding ntawm cov cuab yeej tau sib sau ua ke ntawm ib qho chaw. Hauv qhov no, qhov hluav taws xob tseem ceeb ntawm 380 V yuav raug siv rau qhov pib ntawm txhua qhov windings. Feem ntau, ntawm tag nrho cov kab kos duab, cov qauv no tau qhia tias yog Y.
Nyob rau hauv rooj plaub ntawm kev siv "delta" txoj kev sib txuas, lub stator windings ntawm lub tshuab hluav taws xob txuas nrog hauv series. Ntawd yog, qhov kawg ntawm thawj winding txuas nrog rau qhov pib ntawm qhov thib ob, uas, nyob rau hauv lem, txuas nrog lub thib peb. Lub tom kawg yuav ua kom tiav Circuit Court, txuas nrog qhov pib ntawm thawj.
Qhov sib txawv hauv kev sib txuas lus
Lub "hnub qub" thiab "daim duab peb sab" circuits ntawm lub tshuab hluav taws xob yogtib txoj kev los txuas lawv. Lawv txawv ntawm ib leeg, muab ntau hom kev ua haujlwm. Yog li, piv txwv li, kev sib txuas siv Y scheme muab kev ua haujlwm softer thaum piv nrog delta-txuas motors. Qhov sib txawv no ua lub luag haujlwm tseem ceeb hauv kev xaiv lub zog ntawm cov khoom siv hluav taws xob.
Ntau lub cav muaj zog tsuas yog ua haujlwm ntawm "daim duab peb sab". Lub hnub qub-delta lub cev sib txuas yog qhov zoo heev rau cov ntawv thov uas yuav tsum tau pib muag muag. Thiab thaum lub sijhawm, hloov ntawm windings kom muaj zog tshaj plaws.
Nws yog ib qho tseem ceeb uas yuav tsum tau ntxiv ntawm no: txuas Y lav kev ua haujlwm du, tab sis lub cav yuav tsis tuaj yeem ncav cuag nws lub npe lub zog.
Ntawm qhov tod tes, delta-star-wye lub cev muaj zog txuas yuav muab lub zog ntau dua, tab sis qhov pib tam sim no rau cov cuab yeej tseem yuav nce ntxiv.
Nws yog qhov sib txawv ntawm lub zog ntawm Y kev sib txuas thiab daim duab peb sab uas yog qhov taw qhia tseem ceeb. Lub tshuab hluav taws xob nrog lub hnub qub Circuit Court yuav muaj li 1.5 npaug ntawm lub zog tsawg dua li lub cev muaj zog delta, txawm li cas los xij, qhov kev sib txuas no yuav pab txo qhov pib tam sim no. Txhua qhov kev sib txuas uas suav nrog ob txoj kev sib txuas sib txuas ua ke. Feem ntau lawv tsuas yog siv rau hauv cov xwm txheej uas yuav tsum tau pib lub tshuab hluav taws xob nrog lub npe loj zog.
Start-up scheme "star-delta" rau lub tshuab hluav taws xob muaj lwm qhov zoo dua. Kev xa tawm yog ua tiav hauv Y-tus qauv, uas txo qhov pib tam sim no. Thaum lub cuab yeej khaws nrawm txaus thaum lub sijhawm ua haujlwm, nws hloov mus rau lub tswv yim delta kom ua tiav lub zog siab tshaj plaws.
kev sib txuas ua ke
Lub hnub qub-delta hloov lub tswv yim ntawm lub tshuab hluav taws xob feem ntau yog siv nyob rau hauv cov xwm txheej uas yuav tsum tau pib lub cav nrog qhov tsawg kawg nkaus pib tam sim no. Tab sis tib lub sij hawm, tag nrho cov hauj lwm yuav tsum tau ua nyob rau hauv "daim duab peb sab" kev twb kev txuas. Txhawm rau tsim qhov hloov pauv no, tshwj xeeb peb-theem contactors yog siv. Ob qho xwm txheej yuav tsum tau ua kom tau txais kev hloov pauv tsis siv neeg ntawm cov phiaj xwm. Ua ntej, txhawm rau xyuas kom meej tias cov neeg raug kaw los ntawm kev qhib ib txhij. Qhov thib ob, txhua txoj haujlwm yuav tsum tau ua nrog ncua sijhawm.
Lub ntsiab lus thib ob yog qhov tsim nyog kom nrog 100% qhov tshwm sim yuav raug kaw tag nrho ntawm "lub hnub qub" ua ntej tig rau "daim duab peb sab". Yog tias qhov no tsis ua tiav, ces qhov luv luv yuav tshwm sim thaum lub sijhawm hloov ntawm cov theem. Txhawm rau ua kom tiav cov xwm txheej tsim nyog, siv lub sijhawm txuas nrog ncua ntawm 50 txog 100 milliseconds.
Kev ua raws sijhawm ncua
Thaum siv txoj kev sib txuas hnub qub-delta sib txuas, muaj lub sijhawm relay rau kev hloov qeeb yog tsim nyog. Cov kws tshaj lij feem ntau xaiv ib qho ntawm peb txoj hauv kev:
- Kev xaiv thawjyog nqa tawm siv ib txwm qhib kev sib cuag ntawm lub sij hawm relay. Hauv qhov no, RT yuav kaw qhov kev sib txuas ntawm delta thaum pib, thiab tam sim no relay RT yuav yog lub luag haujlwm hloov pauv.
- Qhov kev xaiv thib ob suav nrog kev siv lub sijhawm tam sim no relay nrog kev hloov pauv ncua ntawm 6 txog 10 vib nas this.
- Txoj kev thib peb yog tswj lub cev muaj zog contactors los ntawm cov khoom siv tsis siv neeg lossis manually.
Kev txiav txim siab ntawm kev hloov pauv
Kev siv cov classic version nrog kev siv lub sijhawm relay rau kev sib xyaw hnub qub-delta circuits yav tas los suav tias yog qhov zoo tshaj plaws. Nws tsuas muaj ib qho tsis zoo, uas qee zaum dhau los ua qhov tseem ceeb - qhov ntev ntawm RV nws tus kheej. Cov khoom siv no tau ua kom ntseeg tau tias lub sijhawm hloov pauv tau ncua sijhawm los ntawm kev sib nqus ntawm cov tub ntxhais. Txawm li cas los xij, cov txheej txheem thim rov qab tau siv sijhawm.
Tam sim no, xws li RV thiab lwm yam khoom siv tau hloov pauv los ntawm cov khoom siv niaj hnub no - zaus hloov pauv. Hloov lub hnub qub-delta lub cev muaj zog nrog lub inverter muaj qhov zoo. Qhov no suav nrog kev ua haujlwm ruaj khov dua, qis pib tam sim no.
Cov cuab yeej no muaj lub microprocessor built-in lub luag haujlwm hloov qhov zaus. Yog tias peb xav txog qhov tseem ceeb ntawm lub inverter rau lub tshuab hluav taws xob, ces nws lub hauv paus ntsiab lus ntawm kev ua haujlwm yog raws li nram no: lub converter generates qhov xav tau zaus ntawm alternating tam sim no. Txog hnub tim, kev lag luam siv tshwj xeeb lossis universal inverter qauv raukev sib txuas ntawm asynchronous motors.
Cov qauv tshwj xeeb yog tsim thiab siv nrog qee hom cav. Universal siv tau nrog txhua yam khoom siv.
Scheme flaws
Txawm tias qhov tseeb tias txoj kev sib txuas classic yog qhov yooj yim thiab txhim khu kev qha, nws muaj qee qhov tsis zoo.
Ua ntej, nws yog ib qho tseem ceeb heev kom raug txiav txim siab lub nra ntawm lub cev muaj zog. Txwv tsis pub, nws yuav siv sij hawm ntev heev kom tau txais lub zog, uas, dhau los, yuav tsis suav nrog qhov muaj peev xwm hloov pauv mus rau delta Circuit Court siv tam sim no relay. Nyob rau hauv hom no, nws yog undesirable mus khiav lub tshuab hluav taws xob rau lub sij hawm ntev.
Thib ob, nrog rau txoj kev sib txuas zoo li no, overheating ntawm windings yog ua tau, uas yog vim li cas cov kws txawj pom zoo kom txhim kho ib qho ntxiv thermal relay hauv Circuit Court.
Thib peb, thaum siv lub sijhawm niaj hnub relays, nws yog ib qho tsim nyog yuav tsum ua tib zoo saib xyuas cov ntawv hla tebchaws ntawm lub tshuab hluav taws xob.
Zoo kawg
Thaum siv lub hnub qub-delta kev twb kev txuas, nws yog ib qho tseem ceeb heev kom raug xam cov load ntawm lub cev muaj zog ncej. Lwm qhov tsis txaus ntseeg nyob hauv qhov tseeb tias thaum lub sijhawm hloov ntawm Y mus rau daim duab peb sab, thaum lub cav tseem tsis tau txais qhov tsim nyog ceev, nws tus kheej induction tshwm sim. Lub sijhawm no, muaj qhov nce voltage hauv lub network. Qhov no ua rau muaj kev puas tsuaj rau lwm cov khoom siv thiab cov khoom siv txuas nrog tib lub network.
