Nws tuaj yeem hais tias tsis muaj qhov tsis meej: pab pawg kws tshaj lij hluav taws xob tam sim no sib xyaw, thiab tsis muaj ob peb tus kws tshaj lij hluav taws xob ua haujlwm tom qab kev kawm me ntsis, thiab ntau tus kws tshaj lij hluav taws xob muaj txiaj ntsig rau kev paub thiab kev ua haujlwm, thiab qee zaum txawm tsis quav ntsej txog kev sib koom ua ke ntawm kev paub txog theoretical. hluav taws xob engineering thiab kuv tau kawm ntau yam uas kuv tsis nco qab txawm tias cov kev paub txog hluav taws xob. Txoj kev ntawm cov kws hluav taws xob tsis yooj yim taug kev. Puas yog technology tiag tiag lossis tsuas yog messing ib puag ncig? Lo lus nug no kuj tsim nyog xav txog!
1. Dab tsi yog qhov zoo thiab qhov tsis zoo ntawm peb hom kev ua haujlwm ntawm qhov nruab nrab ntawm lub zog hluav taws xob?
1. Qhov zoo ntawm qhov nruab nrab point ungrounded system:
Thaum cov av ib ntus tshwm sim hauv cov kab ke no, cov khoom siv hluav taws xob peb-theem tuaj yeem ua haujlwm ib txwm, thiab nws raug tso cai ua haujlwm ib ntus tsis pub dhau ob teev, yog li kev ntseeg siab yog siab;
Disadvantage: Thaum ib-theem grounding tshwm sim nyob rau hauv lub system no, lwm yam ob yam tsis zoo theem-rau-hauv av voltages nce mus rau cov kab voltage, uas yog √3 npaug ntawm ib txwm, yog li cov rwb thaiv tsev yuav tsum siab thiab cov nqi rwb thaiv tsev yog nce.
2. Qhov zoo ntawm nruab nrab point grounding system ntawm arc suppression coil:
Ntxiv rau qhov zoo ntawm qhov nruab nrab point ungrounded system, nws kuj tuaj yeem txo cov av tam sim no;
Nws qhov tsis zoo: zoo ib yam li qhov nruab nrab ntawm qhov tsis sib haum xeeb.
3. Qhov zoo ntawm qhov nruab nrab point direct grounding system:
Thaum ib theem av tshwm sim, lwm qhov tsis zoo ntawm ob theem-rau-hauv av voltages tsis nce, yog li tus nqi rwb thaiv tsev tuaj yeem txo;
Disadvantages: Thaum ib-theem grounding luv luv Circuit Court tshwm sim, lub luv luv-circuit tam sim no loj, thiab faulty qhov yuav tsum tau muab tshem tawm sai sai, ua rau tsis zoo zog mov kev cia siab rau.
2. Dab tsi yog txoj hauv kev rau kev tswj ceev ntawm nyias DC motors? Dab tsi yog cov yam ntxwv ntawm ntau txoj kev tswj kev ceev?
Muaj peb txoj kev tswj hwm ceev rau nyias muaj nyias DC motors:
1. Txo qhov armature voltage rau kev tswj ceev.
2, armature circuit series kuj ceev tswj.
3. Tsis muaj zog magnetic ceev tswj.
Nta ntawm ntau yam ceev-kho txoj kev:
1. Txo cov armature voltage rau kev ceev ceev: lub armature Circuit Court yuav tsum muaj ib tug voltage-adjustable DC fais fab mov, qhov kev tiv thaiv ntawm armature Circuit Court thiab excitation Circuit Court yog me me li sai tau, lub voltage yog txo thiab ceev yog txo, hardness ntawm cov yam ntxwv dag tseem tsis hloov pauv, kev khiav ceev yog qhov ruaj khov, thiab kev ua haujlwm tsis muaj zog tuaj yeem ua tau. ceev.
2. Armature circuit string resistance regulation ceev: qhov loj dua txoj hlua tsis kam, lub softer lub mechanical zog thiab lub unstable ntau rotational ceev. Thaum qis ceev, txoj hlua tsis kam yog loj, lub zog poob kuj ntau dua, thiab qhov ua tau zoo yuav qis dua. Qhov ntau ntawm kev tswj ceev yog cuam tshuam los ntawm qhov loj ntawm lub thauj khoom, qhov ntau ntawm kev tswj ceev yog qhov dav thaum lub thauj khoom loj, thiab qhov ntau ntawm kev tswj ceev yog me me thaum lub teeb yog lub teeb.
3. Kev tswj ceev tsis muaj zog: feem ntau DC motors, txhawm rau kom tsis txhob muaj kev sib nqus ntau dhau ntawm cov hlau nplaum, tsuas yog cov hlau nplaum tsis muaj zog tsis tuaj yeem ua kom muaj zog sib nqus, lub armature voltage tswj tus nqi ntsuas, armature circuit series tsis kam, excitation Circuit Court kuj Rf yog nce, thiab lub excitation tam sim no Thiab cov hlau nplaum flux txo, lub cev muaj zog ceev nce tam sim ntawd, thiab cov neeg kho tshuab zog ua mos.
Thaum qhov ceev nce, yog tias lub load torque tseem nyob ntawm tus nqi ntsuas, lub cev muaj zog lub cev muaj zog yuav dhau lub zog ntsuas, thiab lub cev muaj zog yog overloaded, uas tsis tso cai, yog li thaum lub teb tsis muaj zog yog hloov kho, raws li lub cev muaj zog nce. , lub load torque Correspondingly txo, nws belongs rau lub zog ceev ceev tswj. Txhawm rau tiv thaiv lub rotor winding ntawm lub cev muaj zog los ntawm kev puas tsuaj vim yog lub zog centrifugal ntau dhau, nws yuav tsum raug sau tseg tias lub cev muaj zog ceev tsis pub dhau qhov kev txwv tsis pub dhau lub sijhawm ua haujlwm tsis muaj zog.
3. Dab tsi yog qhov txawv ntawm shunt-excited DC lub cev muaj zog thiab series-excited DC lub cev muaj zog? Dab tsi load yog txhua tus haum rau?
Lub shunt DC lub cev muaj zog mechanical yam ntxwv, qhov ceev hloov me ntsis nrog lub load, lub magnetic flux yog ib tug tas li tus nqi, thiab lub torque hloov proportionally nrog lub armature tam sim no. Nyob rau hauv tib lub sijhawm, qhov pib torque yog me dua li ntawm series lub cev muaj zog, uas tsim nyog rau kev ceev ceev. ruaj khov, thiab loads tsis muaj tshwj xeeb yuav tsum tau rau pib torque.
DC series-zoo siab DC lub cev muaj zog muaj cov yam ntxwv ntawm cov neeg kho tshuab, qhov ceev sib txawv nrog cov load, qhov ceev ceev yog ceev thaum lub teeb, thiab qhov ceev yog qeeb thaum lub load hnyav, lub torque yog kwv yees li proportional rau lub square. armature tam sim no, thiab qhov pib torque loj dua li ntawm lub tshuab shunt. Nws yog qhov tsim nyog rau kev thauj thiab rub cov tshuab uas yuav tsum muaj qhov tshwj xeeb loj pib torque tab sis tsis xav tau qhov kev ruaj ntseg ntawm kev sib hloov ceev.
4. Dab tsi feem ntau yog siv los pib lub qhov txhab peb-theem asynchronous lub cev muaj zog? Dab tsi yog qhov zoo thiab qhov tsis zoo ntawm txhua txoj kev?
Feem ntau muaj ob txoj hauv kev los pib lub qhov txhab asynchronous lub cev muaj zog:
1. Peb-theem symmetrical sib txawv kuj pib ntawm rotor circuit series
Txoj kev no tuaj yeem tsis tsuas txwv qhov pib tam sim no, tab sis kuj nce lub zog pib. Yog tias tus nqi ntawm cov kev ua haujlwm tau zoo, nws tseem tuaj yeem ua rau qhov pib torque ze rau qhov siab tshaj plaws torque rau kev pib, thiab tsim nyog ua kom lub zog ntawm cov kev ua haujlwm ntawm lub series, yog li ntawd qhov pib kuj tseem siv tau rau kev tswj ceev. Resistor yog siv rau ob lub hom phiaj. Lawv tsim nyog rau cov loads xav tau loj pib torque thiab ceev tswj. Disadvantages: Cov kev hloov kho ntau theem tswj Circuit Court yog qhov nyuaj dua, thiab kev tiv thaiv siv ntau lub zog.
2. Lub rotor Circuit Court yog txuas nrog nyob rau hauv series nrog ib tug zaus rheostat pib
Thaum pib ntawm kev pib, lub rotor Circuit Court zaus yog siab, qhov sib npaug kuj thiab inductive reactance ntawm zaus rhiab varistor nce, txwv qhov pib tam sim no kuj nce lub zog pib, raws li qhov ceev nce, zaus ntawm lub rotor Circuit Court txo, thiab qhov sib npaug impedance kuj txo qis. , Tom qab pib, tshem tawm cov zaus rhiab varistor. Qhov zoo: cov qauv yooj yim, kev lag luam thiab pheej yig, tsis xav tau kev hloov kho hauv nruab nrab ntawm kev pib, kev tswj kom yooj yim, thiab pib hnyav-load.
5. Feem ntau siv cov kauj ruam-down pib txoj kev rau tawb-hom peb-theem asynchronous motors: Dab tsi yog qhov txawv ntawm Y-△ hloov pib thiab autotransformer step-down pib?
1. Y-△ hloov pib
Rau lub tawb-hom peb-theem asynchronous lub cev muaj zog txuas nrog △ hauv kev ua haujlwm ib txwm, hloov kev sib txuas rau lub hnub qub zoo li thaum pib, kom lub armature voltage txo mus rau 1/√3 ntawm qhov ntsuas voltage. Thaum qhov ceev yog ze rau tus nqi ntsuas, hloov mus rau △ kev sib txuas, thiab tag nrho qhov hluav taws xob ntawm lub cev muaj zog yog qhov qub. khiav. Qhov tseeb pib tam sim no thiab pib lub zog ntawm Y-△ hloov mus rau 1/3 ntawm cov pib ncaj qha, thiab tsuas yog lub teeb-load pib ua tau.
Qhov zoo: Cov khoom pib yog qhov yooj yim hauv cov qauv, kev lag luam thiab pheej yig, thiab yuav tsum tau siv ua ntej;
Qhov tsis zoo: qis pib torque, tsuas yog haum rau kev ua haujlwm ib txwm △ txuas nrog lub cev muaj zog.
2. Autotransformer kauj ruam-down pib (tseem hu ua kev them nyiaj pib)
Thaum pib, siv lub autotransformer kom txo tau lub hwj chim mov voltage thiab ntxiv rau stator winding ntawm lub cev muaj zog los txo qhov pib tam sim no. Thaum qhov ceev yog ze rau tus nqi ntsuas, txiav tawm lub autotransformer thiab khiav nrog tag nrho cov voltage. Lub zog torque yog 2 npaug ntawm qhov pib siab pib (W2 / W1).
Qhov zoo: Nws tsis txwv los ntawm txoj kev sib txuas ntawm lub cev muaj zog winding, thiab tuaj yeem tau txais lub zog pib loj dua li Y-△ hloov; muaj 2-3 cov plugs nyob rau sab thib ob ntawm autotransformer, uas tuaj yeem xaiv los ntawm tus neeg siv, haum rau lub peev xwm loj thiab xav tau pib Motors nrog lub zog siab.
6. Cov kev ntsuas dab tsi tuaj yeem ntsuas los txiav txim siab ua haujlwm ntawm lub transistor hauv Circuit Court?
Qhov yooj yim tshaj plaws tuaj yeem txiav txim siab los ntawm kev ntsuas tus nqi Vce ntawm triode:
Ntawd yog: yog tias Vce ≈ 0, lub raj ua haujlwm nyob rau hauv lub xeev saturated conduction.
Yog tias Vbe ∠ Vce ∠ Ec, nws tuaj yeem txiav txim siab tias txoj haujlwm yog nyob rau hauv lub xeev loj.
Yog tias Vce ≈ VEc, lub transistor ua haujlwm hauv cheeb tsam txiav tawm. Ntawm no (Ec yog cov khoom siv hluav taws xob).
7. Dab tsi yog cov khoom siv feem ntau siv rau busbars? Qhov zoo thiab qhov tsis zoo ntawm txhua qhov yog dab tsi?
Cov khoom siv dav dav rau busbars yog aluminium, steel thiab tooj liab.
Lub resistivity ntawm txhuas busbar yog me ntsis loj dua tooj liab, nws cov hluav taws xob conductivity yog inferior rau cov tooj liab, nws mechanical zog yog me dua tooj liab, thiab nws yog ib qho yooj yim rau corrode thiab oxidize, tab sis nws yog pheej yig thiab lub teeb nyob rau hauv qhov hnyav. .
tooj liab busbars muaj hluav taws xob zoo conductivity, tsis tshua muaj resistivity, siab mechanical zog, thiab zoo tiv thaiv corrosion, tab sis lawv kim heev.
Cov hlau busbar muaj cov hluav taws xob tsis zoo thiab yooj yim rau corrode, tab sis nws yog pheej yig thiab muaj zog txhua yam.
8. Txoj kev xaiv dav dav ntawm kev hloov cua tsis siv neeg yog dab tsi?
1. Qhov ntsuas hluav taws xob ntawm lub tshuab cua tsis siv neeg hloov ntau dua lossis sib npaug ntawm qhov ntsuas hluav taws xob ntawm kab.
2. Qhov ntsuas tam sim no ntawm lub tshuab hluav taws xob tsis siv neeg hloov pauv ntau dua lossis sib npaug ntawm cov khoom thauj tam sim no suav los ntawm Circuit Court.
3. Kev teeb tsa tam sim no ntawm cov thermal tso tawm=qhov ntsuas tam sim no ntawm cov khoom tswj tau.
4. Lub sijhawm mus ncig tam sim no ntawm cov khoom siv hluav taws xob tso tawm yog ntau dua lossis sib npaug ntawm lub ncov tam sim no thaum lub voj voog thauj khoom ua haujlwm ib txwm.
5. Qhov ntsuas hluav taws xob ntawm qhov hluav taws xob tso tawm ntawm qhov tsis siv neeg cua hloov pauv=qhov ntsuas hluav taws xob ntawm kab.
9. Koj nkag siab txog cos Φ yog dab tsi? Cos Φ cuam tshuam rau lub zog hluav taws xob li cas? Dab tsi yog vim li cas rau qhov qis cos Φ? Yuav ua li cas txhim kho tus neeg siv lub cos Φ?
Kev nkag siab ntawm cosΦ: hauv DC Circuit Court, P=UI; nyob rau hauv AC Circuit Court, P=UIcosΦ, qhov twg U thiab kuv yog rms tus nqi ntawm qhov voltage thiab tam sim no, yog li nyob rau hauv lub AC Circuit Court, lub hwj chim ntawm lub load tsis yog tsuas yog tus nqi rms ntawm qhov voltage thiab tam sim no. Nws yog proportional rau cos Φ, thiab cos Φ yog ib tug unitless yam uas txiav txim siab hwj chim, yog li nws yog hu ua lub hwj chim factor.
cos Φ muaj cov teebmeem hauv qab no ntawm lub zog:
(1) Tsawg cos Φ nce qhov hluav taws xob poob thiab lub zog poob ntawm kab.
(2) Qhov qis cos Φ ua rau cov cuab yeej tsim hluav taws xob tsis siv tag nrho, uas yog, kev siv tus nqi qis.
Los ntawm kev cuam tshuam ntawm ob qho tib si saum toj no, nws tuaj yeem pom tias qis cos Φ yog qhov tsis zoo rau kev lag luam hauv lub tebchaws, yog li lub tuam txhab hluav taws xob muab qhov tseem ceeb rau qhov ntsuas no.
Nws yog paub los ntawm cov mis ψ =tg -1 tias nws yog txiav txim los ntawm qhov load factor. Lub capacitive load yog qhov siv tsawg tshaj plaws, thiab txawm tias tsis muaj peev xwm siv tau. Lub inductive load yog dav siv nyob rau hauv kev lag luam, thiab XL yog loj heev, xws li hluav taws xob motors thiab hluav taws xob vuam tshuab. , induction furnaces, transformers, thiab lwm yam. yog tag nrho cov inductive loads. Vim tias XL loj heev thiab loj, cosΦ tsawg heev.
Yog li ntawd, lub ntsiab yog vim li cas rau qhov qis cosΦ yog siv loj ntawm inductive loads nyob rau hauv kev lag luam. Cov txheej txheem los txhim kho tus neeg siv lub zog qhov tseem ceeb yog txuas lub capacitor nyob rau hauv parallel ntawm tus neeg siv cov kab nkag los yog ntawm tus neeg siv khoom.
