Ua rau thiab kev faib tawm ntawm lub zog cable tsis ua haujlwm

 

Ua rau cable tsis ua haujlwm

Qhov ua rau ntawm lub hwj chim cable tsis ua haujlwm tuaj yeem yog qhov nyuaj thiab ntau yam, thiab tuaj yeem faib dav rau hauv pawg hauv qab no:

 

Mechanical puas:

 

Kev puas tsuaj txhua yam yog ib qho ua rau lub hwj chim cable tsis ua haujlwm, suav nrog ntau feem ntawm txhua kis. Kev puas tsuaj tuaj yeem tshwm sim thaum lub sijhawm teeb tsa, kev thauj mus los, lossis kev ua haujlwm, thiab tuaj yeem ua rau lub cable ua haujlwm tsis zoo lossis ua tsis tiav. Cov laj thawj tseem ceeb ntawm kev puas tsuaj rau cov tshuab muaj xws li:

 

* Kev puas tsuaj rau installation:Kev teeb tsa tsis raug tuaj yeem ua rau lub cable yuav tsum tau khoov, twist, lossis crushed, ua rau puas tsuaj rau lub rwb thaiv tsev lossis tus neeg xyuas pib.

* Kev puas tsuaj sab nraud: Sab nraud quab yuam, xws li kev tsim kho lossis kev ua haujlwm khawb, tuaj yeem ua rau lub cable puas ncaj qha.

* Tsheb khiav:Kev vibrations lossis cuam tshuam los ntawm lub tsheb tsheb tuaj yeem ua rau lub cable puas.

 

Rwb thaiv tsev puas:

 

Kev puas tsuaj rwb thaiv tsev tuaj yeem ua rau lub cable tsis tshua muaj zog tiv thaiv, ua rau tsis ua haujlwm lossis tsis ua haujlwm. Cov laj thawj tseem ceeb ntawm kev puas tsuaj rwb thaiv tsev muaj xws li:

* Cov dej nkag:Cov dej tuaj yeem nkag mus rau hauv lub cable los ntawm qhov tsis xws luag hauv cov rwb thaiv tsev lossis kev txiav tawm, ua rau cov rwb thaiv tsev ntub dej thiab poob nws cov khoom rwb thaiv tsev.

* Kev tsim khoom tsis zoo:Rwb thaiv tsev nrog kev tsim khoom tsis zoo tuaj yeem muaj qhov me me lossis tawg, tso dej nkag mus.

* Kev laus:Nyob rau tib lub sijhawm, lub rwb thaiv tsev tuaj yeem deteriorate, ua nkig thiab nquag tawg.

 

Overvoltage:

 

Overvoltage tuaj yeem ua rau lub rwb thaiv tsev tawg, ua rau luv luv Circuit Court thiab cable tsis ua haujlwm. Cov laj thawj tseem ceeb ntawm overvoltage muaj xws li:

* xob laim ntaus:xob laim tuaj yeem ua rau muaj qhov hluav taws xob tawg uas tuaj yeem ua rau lub cable puas.

* Internal overvoltage:Internal overvoltage tuaj yeem tshwm sim vim kev ua haujlwm tsis raug lossis ua haujlwm tsis zoo hauv lub tshuab hluav taws xob.

 

Tsim thiab tsim khoom tsis xws luag:

Kev tsim tsis zoo thiab kev tsim khoom tsis zoo tuaj yeem ua rau cable tsis ua haujlwm. Cov laj thawj tseem ceeb ntawm kev tsim thiab kev tsim khoom muaj xws li:

* Cov qauv tsim tsis zoo:Kev tsim qauv tsis zoo tuaj yeem ua rau tsis txaus cable sizing, xaiv cov khoom siv tsis raug, lossis tsis muaj kev tiv thaiv ib puag ncig.

* Khoom zoo:Kev siv cov khoom siv tsis zoo tuaj yeem ua rau tsis ua haujlwm ntxov ntxov.

* Cov txheej txheem tsim khoom:Kev puas tsuaj hauv cov txheej txheem tsim khoom, xws li rwb thaiv tsev tsis zoo lossis cov neeg xyuas pib winding, tuaj yeem ua rau cable tsis ua haujlwm.

 

Kev nkag siab txog qhov ua rau lub hwj chim cable tsis ua haujlwm yog qhov tseem ceeb rau kev tiv thaiv thiab txo cov kev ua tsis tiav. Los ntawm kev txheeb xyuas thiab hais txog cov hauv paus ntsiab lus, nws muaj peev xwm txhim kho kev ntseeg tau thiab kev ua neej nyob ntawm lub hwj chim cables.

 

RDCD-IIcable fault test khoomtsim los ntawmWrinduyog lub laub-hom kuaj cov cuab yeej uas tsim nyog rau kev ua haujlwm ntawm qhov chaw thiab kev txav mus los. Nws yog tsuas yog siv rau qhov sib txawv, routing, thiab positioning ntawm lub ntsiab rwb thaiv tsev txhaum cov ntsiab lus ntawm lub hwj chim cables nrog voltage theem ntawm 35kV thiab hauv qab no. Nws tseem tuaj yeem ntsuas qhov tsis kam tiv thaiv thiab luv luv ntawm ntau qhov sib txawv ntawm cov kab hluav taws xob coaxial siab, cov xov tooj hauv zos, cov kab hluav taws xob hauv tsev, thiab cov xaim hauv av. , qhib Circuit Court thiab disconnection faults, raws li zoo raws li siab tiv thaiv to thiab siab tiv thaiv flashover faults. Lub kaw lus muaj plaub chav nyob: RDCD-Ⅱ/502 cable txhaum qhov chaw ua ntej, RDCD-Ⅱ/535T cable kuaj high-voltage teeb liab generator, RDCD-Ⅱ/503D cable txhaum locator, thiab RDCD-Ⅱ/507 underground pipeline detector.

 

Kev faib tawm ntawm cable faults tuaj yeem muab faib ua peb pawg:

series faults, parallel faults, thiab composite faults.

 

(1) Series faults (cov khoom siv hlau tsis xws luag) xa mus rau qhov tsis ua haujlwm ntawm ib lossis ntau lub conductors (xws li cov tawv nqaij sab nrauv) hauv ib lub cable, uas ua rau muaj qhov qhib Circuit Court. Qhov no yog ib hom kev ua txhaum ntawm cable, thiab nws tuaj yeem muab faib ua plaub pawg: qhib ib zaug, qhib ntau lub ntsiab lus, ib kab tawg, thiab ntau kab tawg.

(2) Parallel faults (cov khoom siv rwb thaiv tsev tsis zoo) tshwm sim thaum lub rwb thaiv tsev theem ntawm cov conductors lossis nruab nrab ntawm cov conductors thiab cov tawv nqaij sab nrauv txo qis, ua rau luv luv Circuit Court. Hom kev txhaum no tseem hu ua cable luv Circuit Court, thiab nws tuaj yeem muab faib ua plaub pawg: ib-theem grounding, ob-theem grounding, ob-theem luv Circuit Court, thiab peb-theem luv luv Circuit Court.

(3) Composite faults (ob qho tib si rwb thaiv tsev thiab cov ntaub ntawv hlau muaj qhov tsis xws luag) hais txog kev ua txhaum uas tshwm sim thaum ob qho tib si rwb thaiv tsev thiab cov khoom hlau ntawm lub cable tsis ua haujlwm. Hom kev txhaum no tuaj yeem suav nrog ntau yam tsos mob, xws li ib-theem qhib Circuit Court thiab grounding, ob-theem qhib Circuit Court thiab grounding, ob-theem luv Circuit Court thiab grounding, thiab peb-theem luv Circuit Court thiab grounding.

 

Raws li cov yam ntxwv ntawm rwb thaiv tsev ntawm cov ntsiab lus txhaum, cable faults tuaj yeem muab faib ua plaub pawg: qhib Circuit Court faults, tsis tshua muaj kev cuam tshuam faults, siab tiv thaiv faults, thiab flashover faults, raws li rwb thaiv tsev tiv thaiv Rf thiab tawg qhov sib txawv G ntawm cable txhaum cov ntsiab lus. Txoj kev faib tawm no yog txoj hauv kev yooj yim tshaj plaws rau kev faib cov kab hluav taws xob ua txhaum, tshwj xeeb tshaj yog muaj txiaj ntsig zoo rau kev xaiv txoj kev tshawb nrhiav. Qhov sib npaug Circuit Court ntawm cable faults yog qhia nyob rau hauv daim duab.

 

 

Qhov loj ntawm qhov tawg voltage UG nyob ntawm qhov deb G ntawm qhov txhaum taw tes tawm channel (piv txwv li, tawg qhov sib txawv), qhov loj ntawm cov rwb thaiv tsev tsis kam Rf nyob ntawm qib carbonization ntawm qhov txhaum taw tes cable rwb thaiv tsev, thiab qhov loj ntawm qhov faib capacitance Cf nyob ntawm seb cov dej noo ntawm qhov txhaum taw tes.

 

(1) Nyob rau hauv qhib Circuit Court faults, qhov txuas ntxiv ntawm cable hlau ib feem yog cuam tshuam, tsim ib qho kev tawg, thiab cov khoom siv rwb thaiv tsev ntawm qhov chaw txhaum kuj raug puas tsuaj rau ntau qhov sib txawv. Cov rwb thaiv tsev tiv thaiv Rf ntsuas ntawm qhov chaw nrog megohmmeter yog infinite (∞), tab sis hluav taws xob tawg tuaj yeem tshwm sim thaum DC tiv thaiv qhov ntsuas hluav taws xob; tshawb xyuas qhov txuas ntxiv ntawm cov tub ntxhais hlau xaim qhia qhov tawg. On-site, qhib Circuit Court faults feem ntau tshwm sim nyob rau hauv daim ntawv ntawm ib tug ib-theem los yog ob-theem disconnection grounded.

 

(2) Nyob rau hauv qhov tsis muaj kev tiv thaiv tsis zoo, cov khoom siv hluav taws xob hluav taws xob raug puas tsuaj, ua rau muaj kev cuam tshuam hauv av. Cov rwb thaiv tsev tiv thaiv Rf ntsuas ntawm qhov chaw nrog megohmmeter tsawg dua 10Z0 (Z0 yog cov yam ntxwv ntawm cov kab hluav taws xob impedance, feem ntau ntawm 10 thiab 40Ω). Tsawg tsis kam ua txhaum feem ntau yuav tshwm sim hauv cov hluav taws xob qis hluav taws xob thiab tswj cov kab hluav taws xob ntawm qhov chaw.

 

(3) Nyob rau hauv kev ua haujlwm siab tsis ua haujlwm, cov khoom siv hluav taws xob hluav taws xob raug puas tsuaj, ua rau muaj kev cuam tshuam hauv av. Qhov rwb thaiv tsev tiv thaiv Rf ntsuas ntawm qhov chaw nrog megohmmeter yog ntau dua 10Z0, thiab hluav taws xob tawg tuaj yeem tshwm sim thaum lub sij hawm DC high-voltage pulse test. Kev ua haujlwm siab tsis zoo yog cov kab hluav taws xob ntau tshaj plaws nyob rau hauv high-voltage fais fab cables (6kV lossis 10kV fais fab cables), suav txog ntau dua 80% ntawm tag nrho cov txhaum. Thaum ua qhov ntsuas ntawm qhov chaw, tus sau feem ntau yuav siv Rf=3kΩ raws li qhov pib rau qhov sib txawv ntawm qhov kev ua haujlwm siab thiab qhov tsis zoo tsis kam. Qhov no yog vim hais tias, ntawm Rf=3kΩ, qhov ntsuas qhov tseeb ntawm txoj kev choj nrog qhov ntsuas tam sim no ntawm 10-50mA tuaj yeem tau txais.

 

(4) Nyob rau hauv flashover faults, cov ntaub ntawv rwb thaiv tsev cable puas, ua rau. Cov rwb thaiv tsev tiv thaiv Rf ntsuas ntawm qhov chaw nrog megohmmeter yog infinite (∞), tab sis flashover tawg yuav tshwm sim thaum lub sij hawm DC tiv taus voltage los yog high-voltage mem tes xeem. Flashover faults yog ib qho nyuaj rau kev kuaj xyuas, tshwj xeeb tshaj yog nyob rau hauv kev tiv thaiv kev ntsuam xyuas ntawm cov tshiab nteg cables. On-site, DC flashover txoj kev yog feem ntau siv rau kev tshawb nrhiav.

 

 

Kev faib tawm raws li qhov ua txhaum ntawm qhov ua rau thiab qhov yuam kev ntawm cov yam ntxwv

 

1. Kev Txhaum Txhaum Cai: nthuav tawm qhov kev ntxhov siab

Hauv kev lag luam chaw, blasting faults ua rau muaj kev puas tsuaj, ua rau muaj kev puas tsuaj loj heev thiab kev sib tsoo. Pom tau los ntawm cov pob khoom tawg thiab cov ntawv tooj liab, cov kev ua txhaum no feem ntau ua rau ob-theem luv luv Circuit Court los yog disconnections rau hauv av. Cov yam ntxwv tsis zoo hauv av ua kom yooj yim rau kev tshawb nrhiav, nrog rau kev ntsuas multimeter thiab acoustic muab txoj hauv kev ncaj nraim.

 

2. Kev Ua Phem Txhaum Cai: Kev Tshawb Fawb Txog Kev Ruaj Ntseg

Tig thaum lub sij hawm tiv thaiv kev ntsuam xyuas, kev puas tsuaj txhaum, induced los ntawm DC test voltage, sib tw nrhiav tau vim lawv qhov xwm txheej. Cov ntsiab lus hauv av tseem nyob ruaj khov, thiab cov deformations sab nraud yog tsawg. Kev tshawb pom muaj txiaj ntsig suav nrog kev siv zog xws li "lub voj voog high-voltage" thiab "hluav taws xob rauj" txhawm rau txheeb xyuas cov kev tsis txaus ntseeg no.

 

3. Kev Ua Haujlwm Tsis Txaus: Txiav txim siab qhov nyuaj

Kev ua haujlwm txhaum cai nthuav tawm ib qho kev sib tw thaum lub sijhawm ua haujlwm ntawm lub zog, xws li cable blasting mus rau kev puas tsuaj. Cov teeb meem kev ua haujlwm tshwm sim los ntawm kev teeb tsa tsis raug lossis kev hloov pauv hauv av ntxiv txheej txheej nyuaj. Kev txheeb xyuas cov kev ua yuam kev no yuav tsum muaj kev qhia dav dav, suav nrog kev ntsuas kev tiv thaiv hluav taws xob thiab DC tiv thaiv qhov ntsuas hluav taws xob.

 

Kev nkag siab txog cov khaubncaws sab nraud povtseg ntawm lub zog cable faults yog qhov tseem ceeb rau kev saib xyuas thiab kev daws teeb meem. Kev siv cov kev sim siab tshaj plaws thiab cov cuab yeej tshuaj ntsuam xyuas kom paub meej sai thiab daws teeb meem ntawm cov teeb meem cable, txhawb nqa tag nrho kev ntseeg siab ntawm lub zog hluav taws xob.

 

Decoding Cable Ground Faults: Ua rau thiab Kev Tshawb Nrhiav Txoj Kev

 

1. Kev ua haujlwm hauv av tsis raug: Kev laus thiab corrosion

Kev ua haujlwm cable hauv av faults stems los ntawm ob lub hauv paus ua rau: ntuj aging ntawm rwb thaiv tsev ntev siv thiab sai deterioration ntawm cable sheaths nyob rau hauv corrosive ib puag ncig. Txawm hais tias los ntawm kev laus los yog kev degradation, qhov txo qis hauv qhov hluav taws xob tawg tshwm sim, ua rau cable grounding faults nyob rau hauv rated zaus. Cov kev tshawb nrhiav zoo li "Low Voltage Return Line" thiab "Electric Hammer" ua pov thawj zoo hauv kev nthuav tawm cov kev ua txhaum no.

 

2. High-Resistance Faults: Unraveling Complexity

High-resistance cable faults poob rau hauv ob pawg raws li qhov tseem ceeb ntawm kev ua haujlwm: cable high-resistance faults thiab cable low-resistance faults. Txoj kev "High-Voltage Loop" thiab "Electric Hammer" txoj hauv kev ua lub luag haujlwm tseem ceeb hauv kev txheeb xyuas thiab qhia txog qhov tsis zoo no. Kev kuaj xyuas qhov kev hloov pauv thaum lub sij hawm DC tiv thaiv kev ntsuam xyuas muab kev nkag siab rau hauv cov kab mob, txawm tias muaj kev cuam tshuam rau kev puas tsuaj los yog tsis muaj zog.

 

3. Moisture-Induced Faults: Kev Xeem Tshaj Tawm

Moisture-induced faults, feem ntau tshwm sim los ntawm dej ingress mus rau hauv lub cable lub ntsiab rwb thaiv tsev txheej, ua ib tug tshwj xeeb kev sib tw. Kev tsis zoo, kev tsim kho tsis zoo, lossis kev puas tsuaj sab nraud ua rau muaj qhov tsis zoo no. Txoj kev "High-Voltage Choj" yuav tsum yog qhov tseem ceeb, tshwj xeeb tshaj yog thaum ya raws cuam tshuam cov qauv ib txwm ua raws li txoj hauv kev "Pulse Thib Ob" lossis "Peb Pulse". Kev ntsuas ntxiv, xws li arc hlawv, tej zaum yuav xav tau rau qhov chaw ua txhaum cai.

 

To taub qhov intricacies ntawm cable hauv av faults yog qhov tseem ceeb rau kev soj ntsuam thiab saib xyuas. Kev siv kev sib xyaw ua ke ntawm cov txheej txheem tshawb nrhiav kom haum rau cov yam ntxwv txhaum cai ua kom muaj kev qhia dav dav rau kev daws teeb meem thiab txhim kho tag nrho cov kev ntseeg siab ntawm cov kab hluav taws xob.