Yog vim li cas rau voltage poob rau hauvxlp kab
Voltagedrop "yog qhov poob qis, thiab qhov poob qis ntawm XLPE cable yog vim qhov tsis kam ntawm tus neeg xyuas pib. Vim li no, tsis hais cov khoom siv rau tus neeg xyuas pib (tooj liab / aluminium), nws yuav ua rau qee qhov tsis zoo ntawm cov khoom siv hluav taws xob. Circuit Court, thiab thaum qhov poob (voltage poob) tsis ntau tshaj 5% ntawm nws tus kheej voltage, nws feem ntau tsis muaj qhov tshwm sim ntawm lub zog tsav ntawm lub Circuit Court.
Piv txwv li, rau 380V kab, yog tias qhov hluav taws xob poob rau 19V, uas txhais tau hais tias qhov hluav taws xob hluav taws xob tsis qis dua 361V, yuav tsis muaj teeb meem loj. Tau kawg, peb cia siab tias qhov kev poob siab no yuav tsawg li tsawg tau. Vim hais tias lub siab nws tus kheej yog ib qho hluav taws xob poob, txawm hais tias nws yog ib qho kev inevitable, peb ib txwm cia siab tias qhov poob siab nyob rau hauv ib qho kev lees paub.
Kev suav cov mis rau voltage poob ntawmXLPE cable
Feem ntau hais lus, xam qhov poob siab ntawm XLPE cable tsis nyuaj thiab tuaj yeem ua tau los ntawm kev ua raws li cov kauj ruam no:
Feem ntau hais lus, xam qhov poob siab ntawm XLPE cable tsis nyuaj thiab tuaj yeem ua tau los ntawm kev ua raws li cov kauj ruam no:
1. Xam cov kab tam sim no I
I= P/1.732 × U × cosθ
Ntawm lawv: P-power (kW); U-voltage (kV); Cos θ - fais fab mov (0.8-0.85)
2. Xam cov kab tsis kam R
R=ρ×L/S
Ntawm lawv: ρ - conductor resistivity (tooj liab core cable ρ=0.01740, aluminium conductor ρ=0.0283); L - Kab ntev (meters); Nominal cross-section ntawm S-cable
3. Xam cov kab hluav taws xob poob (yooj yim thiab ua tau zoo tshaj plaws):
ΔU=I×R
Kev suav cov qauv rau kab hluav taws xob poob: △ U=2 * I * R, I - kab tam sim no; L - Kab ntev
Yuav ua li cas xam cable voltage poob?
Ua ntej xaiv cov hlau thiab tom qab ntawd xam qhov voltage poob. Lub hauv paus ntsiab lus ntawm kev xaiv cov hlau yog:
Txwv qhov ntu ntu ntawm cov xaim raws li cov cua sov ntawm qhov chaw nyob ze (kev nyab xeeb nqa tam sim no);
Raws li kev nyab xeeb tam sim no nqa lub peev xwm ntawm qhov ntev, cov hlau hla ntu yuav tsum raug xaiv raws li qhov tsis muaj hluav taws xob los xyuas kom meej tias qhov ua haujlwm voltage ntawm qhov chaw thauj khoom yog nyob rau hauv qhov tsim nyog;
Xaiv raws li kev lag luam tam sim no ceev rau cov khoom hnyav.
Qhov tso cai tam sim no ceev kom ntseeg tau tias kev ua haujlwm tsis tu ncua ntawm cov xaim rau lub sijhawm ntev yog hu ua lub peev xwm nqa tam sim no. Txoj cai dav dav yog xaiv 5-8A/mm ² tooj liab hlau; Aluminium hlau yuav tsum raug xaiv ntawm 3-5 A/mm ². Lub peev xwm nqa tam sim no muaj kev nyab xeeb yuav tsum tau txiav txim siab raws li cov khoom siv dav dav xws li qhov kub siab tshaj plaws, qhov txias txias, thiab tso cov xwm txheej ntawm cov tub ntxhais hlau siv ib puag ncig ntawm cov hlau.
Nyob rau hauv dav dav, nrog luv luv, me me cross-sectional cheeb tsam, zoo tshav kub dissipation, thiab tsis kub, conductivity ntawm hlau yog muaj zog, thiab lub sab sauv txwv tsis pub nqa tam sim no; Vim qhov kev ncua deb, qhov loj ntawm qhov hla ntu, tsis muaj cua sov dissipation, qhov kub thiab txias, ib puag ncig tsis zoo, thiab lwm yam, cov khoom siv hluav taws xob ntawm cov hlau tsis muaj zog, thiab cov kev txwv qis rau kev nyab xeeb tam sim no raug xaiv;
Xws li cov khoom siv hluav taws xob, cov xov hlau liab qab muaj zog dua li cov xov hlau insulated, cov xov hlau siv hluav taws xob muaj zog dua cov kab hluav taws xob, cov kab hluav taws xob faus muaj zog dua cov kab hauv av, thiab lwm yam.
Voltage poob yog xam raws li hauv qab no tej yam kev mob:
ambient kub yog 40 degree; Qhov kub ntawm cov hlau yog 70-90 degree ; Cable kev npaj: ib leeg tub ntxhais, S=2D; hwj chim factor cos θ=0.8; Qhov tso cai feem pua ntawm qhov txo qis ntawm qhov kawg yog Tsawg dua lossis sib npaug li 5%.
Ntawm lawv: Vd - voltage poob, Vd=KxIxLxV0 (v); I - Ua haujlwm tam sim no lossis suav tam sim no (A); L - Kab ntev (m); V0- Hauv rooj voltage (V/Am); K: Peb theem plaub hlau K=√ 3 theem ib zaug K=1
Tso cai qhov hluav taws xob poob thaum lub sijhawm ua haujlwm ib-theem: Vd=220Vx5%=11V
Tso cai voltage poob thaum lub sijhawm ua haujlwm peb theem: Vd=380Vx5%=19V
