Dab tsi yog lub zog dielectric ntawm dielectric? Cia peb sim nkag siab lo lus no, txhawm rau txheeb xyuas cov yam ntxwv ntawm qhov ntsuas no.
Definition
Dielectrics yog cov khoom uas tsis ua hluav taws xob zoo lossis tag nrho. Tus nqi ntawm qhov ntom ntawm xws li cov khoom ntawm tus nqi thauj khoom (electrons) tsis tshaj 108 pieces ib cubic centimeter. Lub ntsiab yam ntxwv ntawm cov khoom siv hluav taws xob insulating yog lawv lub peev xwm los polarize nyob rau hauv ib qho chaw sab nraud. Dielectrics muaj xws li gaseous tshuaj, ntau yam resins, iav, thiab cov ntaub ntawv polymeric. Lub chemically ntshiab insulator yog dej.
Dielectric yam ntxwv
pab pawg no suav nrog pyroelectrics, ferroelectrics, relaxors, piezoelectrics. Passive thiab active zog ntawm cov ntaub ntawv no nquag siv nyob rau hauv niaj hnub technology, yog li peb yuav nyob rau hauv lawv nyob rau hauv ntau nthuav dav.
Cov khoom tsis muaj zog ntawm cov insulators siv thaum lawv siv hauv cov khoom siv pa.
Cov khoom siv hluav taws xob hluav taws xob yog cov khoom siv hluav taws xob uas tsis tso cai rau kev poob hluav taws xob. Nrog lawv cov kev pab, nws muaj peev xwm cais cov hluav taws xob circuits ntawm ib leeg, cov khoom siv los ntawm cov khoom siv hluav taws xob. Hauv cov xwm txheej zoo li nopermittivity tsis muaj lub luag haujlwm tshwj xeeb.
Active (tswj) dielectrics yog pyroelectrics, ferroelectrics, electroluminophores, cov ntaub ntawv rau shutters thiab emitters nyob rau hauv laser technology.
Kev thov rau cov khoom siv dielectric yog nce txhua xyoo. Yog vim li cas yog qhov nce hauv lub peev xwm ntawm cov tuam txhab lag luam thiab cov tuam txhab lag luam.
Ntxiv rau, qhov xav tau ntau ntxiv rau dielectrics tuaj yeem piav qhia los ntawm kev nce hauv kev sib txuas lus thiab ntau yam khoom siv hluav taws xob.
Nyob hauv thev naus laus zis, lub zog hluav taws xob ntawm cov insulators yog qhov tseem ceeb tshwj xeeb, cuam tshuam nrog kev teeb tsa ntawm cov molecules thiab atoms hauv cov siv lead ua lattice.
Kev faib tawm
Nyob rau hauv cov xwm txheej sib txawv, cov khoom siv dielectric tuaj yeem pom cov yam ntxwv sib txawv ntawm cov insulating, uas txiav txim siab txog qhov kev thov ntawm nws daim ntawv thov. Piv txwv li, lub zog dielectric hloov nrog qhov kub thiab txias.
Nyob ntawm cov qauv, cov khoom siv hluav taws xob organic thiab inorganic inorganic yog qhov txawv.
Raws li kev lag luam hluav taws xob tsim, yog li tau tsim cov khoom siv dielectric los ntawm cov zaub mov. Cov thev naus laus zis tsis ntev los no tau txhim kho ntau heev uas nws tuaj yeem txo qis tus nqi ntawm kev tsim khoom, vim li ntawd, cov ntxhia dielectrics tau hloov tshuaj thiab cov khoom siv ntuj tsim.
Cov khoom siv ntxhia dielectric
Cov tebchaw xws li:
- Txhim kho, alkaline, teeb,capacitor iav, muaj cov sib tov sib txawv ntawm cov oxides. Thaum ua oxides ntawm txhuas, calcium, silicon, lub zog hluav taws xob ntawm cov khoom nce.
- iav enamels yog cov khoom siv hauv txheej txheej nyias ntawm cov enamel yog siv rau saum npoo hlau.
- Lub teeb qhia, uas yog hom tshwj xeeb ntawm lub teeb ua fiberglass.
- Ceramic khoom.
- Mica.
- Asbestos.
Txawm hais tias muaj ntau yam khoom siv hluav taws xob insulating, nws tseem nyob deb ntawm ib txwm muaj peev xwm hloov ib lub dielectric nrog lwm tus.
Lub zog hluav taws xob ntawm cov rwb thaiv tsev yog ib qho khoom tseem ceeb, tab sis nws tsis yog tib qho uas yuav tsum tau saib xyuas thaum xaiv cov khoom zoo li no.
Kev saib xyuas tshwj xeeb kuj tau them rau thermal, mechanical, lwm yam khoom siv lub cev thiab tshuaj, suav nrog kev muaj peev xwm rau ntau hom kev ua, nqi, khoom siv.
Tshawb xyuas lub zog hluav taws xob ntawm cov rwb thaiv tsev yog ua kom ntseeg tau tias muaj kev nyab xeeb siab tshaj plaws ntawm kev ua haujlwm ntawm cov twj paj nruag thiab cov khoom siv.
Electrical insulating petroleum oils
Transformer roj, siv rau lub hwj chim transformers, muaj qhov siab tshaj plaws kev faib tawm hauv hluav taws xob engineering ntawm cov ntaub ntawv insulating kua. Lawv sau cov pores nyob rau hauv lub fibers rwb thaiv tsev, qhov kev ncua deb ntawm lub windings, tsub kom lub dielectric zog ntawm rwb thaiv tsev, txhawb kev tshem tawm cua sov. Tsis tas li ntawd, cov roj transformer yog nquag siv nyob rau hauv high voltage roj Circuit Court breakers. Nyob rau hauv xws li pab kiag li lawm, ntawm divergentcov kev sib cuag ntawm tus tes hloov mus ua txhaum lub hluav taws xob arc, raws li ib tug tshwm sim ntawm cov arc channel yog sai txias thiab extinguished. Txhawm rau kom tau txais cov roj av hluav taws xob hluav taws xob hluav taws xob hluav taws xob, roj siv, ua tiav nws cov txheej txheem distillation nrog cov theem sib cais ntawm ib feem ntawm txhua theem thiab cov ncauj lus kom ntxaws purification los ntawm impurities nrog sulfuric acid, ua raws li kev ntxuav thiab ziab.
Lub zog hluav taws xob ntawm cov roj zoo li no yog qhov muaj txiaj ntsig zoo rau cov dej noo. Txawm tias muaj me ntsis admixture dej nyob rau hauv cov roj, ib tug tseem ceeb txo nyob rau hauv no lub cev kom muaj nuj nqis yog pom. Nyob rau hauv qhov kev txiav txim ntawm ib qho hluav taws xob teb, cov tee dej ntawm emulsified tau kos rau hauv cov chaw uas lub teb lub zog muaj ib tug siab tshaj plaws tus nqi, raws li ib tug tshwm sim ntawm kev puas tsuaj.
Nrog rau qhov txo qis hauv lub zog hluav taws xob ntawm cov roj, nws tsis tsuas yog cov dej molecules xwb, tab sis kuj muaj fiber ntau impurities. Lawv nqus dej, uas cuam tshuam rau cov yam ntxwv hluav taws xob ntawm cov kua dielectric.
kab roj
Lawv yog siv rau hauv kev tsim hluav taws xob fais fab cables. Thaum lawv cov ntawv rwb thaiv tsev yog impregnated nrog roj, qhov kev tshem tawm ntawm tshav kub poob nce.
Muaj ntau hom roj cable. Piv txwv li, rau impregnation ntawm lub hwj chim cables ntawm txhuas thiab txhuas sheaths, roj ntawm lub KM-25 hom yog siv, uas muaj ib tug kinematic viscosity ntawm tsawg kawg yog 23 millimeters ib ob, ib tug ncuav point ntawm tsis ntau tshaj 1000 degrees. Txhawm rau ua kom cov viscosity ntawm cov roj, rosin ntxiv rau nws lossisSynthetic thickener.
Ua ntej siv lub dielectric, sim lub zog dielectric ntawm rwb thaiv tsev.
Ua kua hluavtaws dielectrics
Cov khoom siv hluav taws xob rwb thaiv tsev no yog qhov zoo tshaj plaws ntawm qee yam ntawm cov roj av. Lawv muaj kev nyiam rau kev laus hluav taws xob, uas cuam tshuam tsis zoo rau cov khoom raws li kev cuam tshuam ntawm hluav taws xob ntawm kev siv zog ntau ntxiv.
Yuav daws qhov teeb meem no, capacitors yog impregnated nrog lub polar kua dielectric.
Kev kuaj xyuas lub zog hluav taws xob yog qhov yuav tsum tau ntsuas los xaiv hom insulator zoo tshaj plaws.
Chlorinated hydrocarbons
Lawv tau txais los ntawm ntau yam hydrocarbons los ntawm kev hloov ib lossis ntau dua hydrogen atoms nrog chlorine. Feem ntau hom dielectrics yog chlorinated biphenyl. Nws muaj viscosity siab, muaj cov yam ntxwv tseem ceeb sib xws rau GOST. Lub zog hluav taws xob ntawm lub rwb thaiv tsev no yog siab dua lwm cov roj av uas tsis yog-polar, yog li ntawd, thaum siv nws, lub ntim ntawm lub capacitor yuav luag halved. Ntawm qhov zoo ntawm chlorinated biphenyls, peb qhia txog lawv qhov tsis sib xws, thiab qhov tsis zoo yog toxicity thiab tus nqi siab.
Ntawm cov khoom siv pheej yig hauv tsev nrog cov yam ntxwv zoo insulating, peb qhia txog kev sib xyaw ntawm isobutene thiab nws cov isomers (octol), tau los ntawm cov roj tawg.
Natural insulators
Rosin,uas yog ib tug nkig resin tau los ntawm resin, muaj cov organic acids nyob rau hauv nws muaj pes tsawg leeg. Nws dissolves zoo nyob rau hauv cov roj av thiab yog siv los ua sealing thiab impregnating cable compounds.
Ib txheej nyias ntawm cov roj zaub, ntog ntawm cov khoom siv, tsim cov yeeb yaj kiab nyias, ua kom cov yam ntxwv ntawm cov insulating ntawm ib feem.
Ua rau poob hluav taws xob
Nyob rau hauv cov dielectrics uas siv rau hauv kev xyaum, muaj dawb xwb. Raws li electrons txav, hluav taws xob conductivity nce. Txij li thaum muaj ob peb nqi, cov insulators tau ua tiav qhov kev xeem no. Lub zog hluav taws xob ntawm insulators txiav txim siab thaj chaw tseem ceeb ntawm lawv daim ntawv thov kev lag luam.
Rwb thaiv tsev yog qhov tsim nyog rau kev sib cais tam sim no, tswj qhov kub thiab txias, hluav taws xob lub zog, lwm yam khoom siv thiab cov khoom siv muaj.
Yog tias lub piezoelectric siv los ua dielectric nyob rau hauv lub capacitor, nws hloov nws cov yam ntxwv linear nyob rau hauv lub zog ntawm alternating voltage, hloov mus rau hauv lub generator ntawm ultrasonic vibrations.
Zoo kawg
Technology thiab cov yam ntxwv ntawm kev ua haujlwm ntawm cov khoom siv hluav taws xob thiab hluav taws xob txiav txim siab sib txawv ntawm cov khoom siv dielectric.
Insulators siv rau lub hom phiaj siv tswv yim muaj ob peb lub tshuab hluav taws xob hauv lawv lub ntim, yog li ntawm qhov hluav taws xob tas li lawv dhau qhov tam sim no yam tsawg kawg nkaus, hu ua hluav taws xob tam sim no.
Yog tias qhov hluav taws xob nce,thov rau lub rwb thaiv tsev, tus nqi ntawm lub zog ntawm lub zog hauv lub dielectric yuav ntau dua ib qho nqi, lub insulator yuav poob nws cov hluav taws xob insulating yam ntxwv.
Qhov dhau los ntawm qhov tam sim no uas ntws los ntawm cov insulator nce thiab nws qhov kev tiv thaiv qis, ua rau cov electrodes rau luv Circuit Court.
qhov tshwm sim no hu ua dielectric breakdown. Nyob rau hauv rooj plaub thaum lub voltage thov mus rau lub dielectric nce mus txog ib tug tseem ceeb tus nqi, ib tug ntse nce nyob rau hauv lub tam sim no tau pom, lub voltage ntawm lub electrodes txo, raws li ib tug tshwm sim ntawm irreversible kev hloov, hluav taws xob tsis kam ntawm lub insulator txo.
Nyob ntawm qhov tsis sib xws ntawm lub zog thiab lub zog sib cais, lub txim tshwm sim tom qab tawg, uas ua rau melting, hlawv, tawg, thiab lwm yam kev hloov pauv ntawm dielectric thiab electrodes.
Nrog xaiv txoj cai ntawm cov khoom siv hluav taws xob, koj tuaj yeem ua haujlwm zoo ntawm cov khoom siv hluav taws xob thiab cov cuab yeej siv.
