Dab tsi yog qhov laj thawj uas tuaj yeem ua rau lub capacitors tawg thaum nws tau siv?
Apr 06, 2026| Keeb kwm:
480V capacitor, reactor impedance 7% nrog ib tug 1.35 zaug linear, THDU teem ntawm 12%, lub reactor txuas saum lub capacitor, thiab lub capacitor tawg los yog bulges ncaj qha los ntawm lub hau. Lub AC contactor los ntawm Chint kuj puas. Qhov project yog nyob ntawm Beihai Chemical Plant hauv Guangxi. Lub hwj chim reactive fais fab them nyiaj capacitor ntsia tau tawg sai li sai tau thaum nws tau siv rau, 12 units tawg thiab 6 units tseem nyob twj ywm. Yuav ua li cas yog vim li cas? Nws yog speculated tias qhov tsawg kawg nkaus THDu yog 8% thiab muaj resonance.
I. Direct Cause: Harmonic Resonance Ua rau muaj kev puas tsuaj loj heev
1.1 Resonance tshwm sim li cas?
Lub resonant zaus ntawm LC ceg (7% reactor + capacitor) yog:
Sib raug rau cov3, 78th sib.
Hom kev sib haum xeeb los ntawm cov chaw cog tshuaj (VFDs, rectifiers) suav nrog 3rd (150Hz), 5th (250Hz), thiab 7th (350Hz). Thaum cov yam ntxwv impedance hloov pauv, kev sib haum xeeb nyob ze 3.78 (tej zaum 3rd lossis 4th) tuaj yeem ua kom nrov nrov.
1.2 Lub cev txheej txheem ntawm "tawg tawg thaum lub zog"
Lub sij hawm ntawm capacitor energization → LC Circuit Court tsim → Yog hais tias harmonic Cheebtsam nyob ze 189Hz nyob rau hauv daim phiaj → Parallel los yog series resonance tshwm sim → Harmonic tam sim no amplified 5 ~ 20 zaug
Capacitor kev paub txog tam sim no tshaj nws qhov kev ntsuam xyuas hauv vib nas this → Internal metallized zaj duab xis overheats sai → Dielectric tawg → Ntau cov roj tsim tawm → Siab tawg los ntawm qhov tsis muaj zog tshaj plaws ntawm lub hau saum toj kawg nkaus → tawg (los yog bulging yog tias tsis tso siab rau lub sijhawm)
1.3 Vim li cas tsuas yog 6 ntawm 12 tawg?
Kev faib tsis sib npaug ntawm lub zog resonance ntawm peb theem (ib theem tshwm sim ze rau qhov taw tes resonance)
Kev sib txawv ntawm qhov sib txawv ntawm cov capacitors (thawj cov hauv dais brunt)
Kev hloov pauv ntawm tus kheej (qee qhov capacitors muaj qhov kam rau siab me ntsis)
Tom qab tawg, Circuit Court qhib, tiv thaiv cov capacitors seem
II. Qhov tseem ceeb ntawm kev koom tes: Tsis txaus Reactor Linearity (1.35x)
2.1 "1.35x" txhais li cas?
Cov qauv kev lag luam (piv txwv li, GB / T 1094.6) feem ntau xav tau cov reactors kom tswj tau cov linearity (inductance hloov<5%) up to 1.8x rated current. 1.35x is a significantly low specification, meaning:
Thaum tam sim no tshaj 1.35x tus nqi ntsuas, lub reactor pib magnetize saturate
Tom qab saturation, inductance poob → qhov tseeb reactance piv poob los ntawm 7% mus rau 5% lossis qis dua
Resonance zaus hloov mus (los ntawm 189Hz tej zaum mus rau 200 ~ 250Hz)
2.2 Kev tuag tshwm sim tom qab saturation
| Theem | Phem | Qhov tshwm sim |
|---|---|---|
| Ib txwm | 7% reactance, resonance ntawm 189Hz | Zam kev sib haum xeeb tseem ceeb, nyab xeeb |
| Overcurrent → saturation | Inductance poob, resonance point hloov mus | Tej zaum yuav poob ze ze ntawm 5th harmonic (250Hz) |
| Resonance amplification | 5th harmonic tam sim no amplified | Harmonic tam sim no ntawm capacitor surges |
| Cov lus pom zoo | Siab dua tam sim no → ntxaum saturation → resonance ze dua rau 5th → tam sim no siab dua | Avalanche tsis ua haujlwm |
2.3 Kub ambient kub nyob rau hauv tshuaj nroj tsuag ua phem saturation
Kub ambient kub (lub caij ntuj sov hauv Beihai, Guangxi tuaj yeem ncav cuag 35℃+)
Reactor tsim nws tus kheej cua sov los ntawm tooj liab thiab hlau poob
Qhov kub nce yuav txo qhov sib nqus core permeability → txo qis saturation pib
III. Basic Configuration Flaw: Tsis txaus Margin ntawm 480V Capacitor nrog 7% Reactor
3.1 Voltage nce nyhuv
Nrog rau 7% series reactor, qhov voltage hla lub capacitor ua:
Yog hais tias qhov tseeb qhov system khiav hauj lwm voltage yog 400V (ntau tus nqi), lub capacitor kev paub txog430V, uas zoo nkaus li qis dua nws qhov ntsuas 480V.Txawm li cas los xij:
3.2 Harmonic voltage superposition
Ntawm -site THDu Ntau dua lossis sib npaug li 8%, qhov hluav taws xob waveform yog distorted
Harmonic voltage peaks tuaj yeem nce qhov siab kawg voltage rau1.2 ~ 1.5 npaug ntawm qhov tseem ceeb ncov
Qhov hluav taws xob teb kev ntxhov siab ntawm lub capacitor dielectric mus txog lossis tshaj nws qhov kev txwv tsim
3.3 Kev sib piv xaiv kev nyab xeeb
| Kev xaiv | Voltage withstand nyob rau hauv lub hauv paus | Kev nyab xeeb margin nyob rau hauv ib puag ncig harmonic | Xaus |
|---|---|---|---|
| 480V cap + 7% reactor | ~430V | Tsis txaus | Txaus ntshai |
| 525V cap + 7% reactor | ~430V | Tsim nyog | Kev lag luam pom zoo |
Kev xaiv 480V yog "tseem ceeb heev" rau koj qhov chaw, ua rau lub cev qhuav dej tam sim ntawd thaum lub suab nrov tshwm sim.
IV. Cov yam tseem ceeb: Inrush tam sim no + Residual Charge
4.1 Inrush tam sim no
Capacitor energization tsim ib qho inrush tam sim no ntawm5 ~ 10 zaug ntsuas tam sim no. Nrog rau keeb kwm kev sib haum xeeb uas twb muaj lawm, lub inrush superimposes nrog harmonics, uas ua rau lub ncov siab dua.
4.2 Residual nqi
If the capacitor is not fully discharged after de-energization (requires >3 feeb)
Residual charge tawm voltage hla lub capacitor terminals
Thaum re-energization, residual voltage ntxiv rau muab voltage → tsis tshua muaj siab surge voltage thiab tam sim no → tam sim no dielectric puas
4.3 Cov ntaub ntawv pov thawj los ntawm contactor puas
Qhov puas CHINT AC contactor qhia:
Inrush tam sim no los yog resonance tam sim no tshaj nws cov qhab nia ua peev xwm
Kev sib cuag tej zaum yuav tau welded los yog hlawv tawm
Qhov no ntxiv qhia txog qhov hnyav ntawm qhov tshwm sim overcurrent
V. Ua kom tiav Txoj Kev Ua Tsis Taus (Chronological Order)
VI. Kev Ua Tam Sim No & Kev Kho Kom Zoo
⚠️ Kev Ua Tam Sim No (Yuav tsum tau ua ua ntej rov- zog)
Tsis txhob rov- zog: Tsis txhob hloov cov capacitors thiab energize kom txog rau thaum pom qhov ua rau
Ntsuas lub zog zoo: Tsis muaj lub tsev txhab nyiaj capacitor hauv kev pabcuam, ntsuas qhov kev sib haum xeeb ntawm lub ntsiab lus nkag los txheeb xyuas qhov tseem ceeb ntawm kev sib haum xeeb thiab qhov loj
Check tawm Circuit Court: Txheeb xyuas cov hluav taws xob tawm hluav taws xob yog qhov ua haujlwm tau zoo thiab lub sijhawm tswj lub sijhawm tso tawm ntau dua lossis sib npaug li 3 feeb
🔧 Kev Ua Haujlwm Kho Kom Zoo
| Qhov teeb meem | Kev ntsuas kho | Ua ntej |
|---|---|---|
| Tsis txaus capacitor voltage margin | Hloov nrog 525V rated voltage capacitor | Yuav tsum tau |
| Tsis zoo reactor linearity | Hloov nrog reactors muaj linearity Ntau dua lossis sib npaug rau 1.8x (tseem 7%) | Yuav tsum tau |
| Harmonic resonance txaus ntshai | Nruab Active Power Filter (APF) rau qhov chaw - theem kev sib haum xeeb mitigation | Pom zoo heev |
| Inrush tam sim no cuam tshuam | Hloov AC contactor nrog Thyristor Hloov (TSC) rau xoom- hla kev hloov | Pom zoo |
| Kev tiv thaiv tsis txaus | Ntxiv ceev- ua fuses rau ib ceg capacitor, pab tswj kev tiv thaiv overcurrent/overvoltage | Pom zoo |
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Pom zoo xaiv Parameters (Tom qab kho)
Capacitor525V, 30 kvar (piv txwv li, kho raws li qhov yuav tsum tau muaj peev xwm)
Reactor: 7%, linearity Ntau dua lossis sib npaug rau 1.8x (lossis 2.0x), ntsuas tam sim no xaiv raws li 1.3x capacitor ntsuas tam sim no
Hloov ntaus ntawv: Thyristor hloov (TSC), lossis tshwj xeeb contactor nrog ua ntej -them resistors
Tshem tawm resistor: Xyuas kom tawm mus rau qis dua 50V hauv 3 feeb
VII. Ib -Sentence Summary
Tsis txaus cov npoo ntawm 480V capacitor nrog 7% reactor + low reactor linearity (1.35x, nquag saturation) + muaj zog harmonic keeb kwm nyob rau hauv cov tshuaj cog → tom qab saturation, resonant zaus hloov ua rau harmonic resonance → overcurrent ua rau 6 capacitors tawg los ntawm sab saum toj.
Core kho cov kev ua: upgrade capacitors rau 525V + siv reactors nrog linearity Ntau tshaj los yog sib npaug rau 1.8x + nruab APF rau qhov chaw - theem harmonic mitigation.
Kev nyab xeeb ua ntej. Thov ua kom tiav kev ntsuas hluav taws xob zoo ua ntej hloov khoom siv.