Cov kev cuam tshuam feem ntau hauv kev sib txuas lus digital kub kub feem ntau suav nrog electromagnetic cuam tshuam (EMI), suab nrov impulse, ntau-mode/differential-mode cuam tshuam, xov tooj cua zaus cuam tshuam, thiab hauv av loops tshwm sim los ntawm kev tsis zoo hauv av. Cov kev cuam tshuam no cuam tshuam rau kev ncaj ncees ntawm kev sib txuas lus los ntawm hluav taws xob lossis kev coj ua, ua rau cov ntaub ntawv yuam kev, kev cuam tshuam ntawm node, thiab txawm tias tswj tsis tau.
1. Electromagnetic Interference (EMI) – Qhov kev cuam tshuam ntau tshaj plaws. Ua los ntawm electromagnetic teb tsim los ntawm siab - cov khoom siv hluav taws xob ua haujlwm hauv kev cob qhia, nws yog hom kev cuam tshuam tseem ceeb tshaj plaws hauv cov tshuab kub khiav.
Qhov chaw tseem ceeb:
Inverters thiab servo drives: Siab - zaus PWM teeb liab tsim hluav taws xob hluav taws xob dav dav;
Kev hloov hluav taws xob hloov hluav taws xob: Lub sijhawm tam sim no surges nyob rau hauv PID tswj tsim kev hloov hluav taws xob tsis zoo;
Hloov cov khoom siv hluav taws xob: Rectification thiab siab - zaus hloov cov txheej txheem tsim dv/dt thiab di/dt suab nrov.
Propagation paths:
Radiative coupling: Unshielded cables ua raws li "antennas" kom tau txais electromagnetic nthwv dej ntawm qhov chaw;
Conductive coupling: Xa mus rau qhov kev sib txuas lus module los ntawm cov kab hluav taws xob lossis cov xaim hauv av.
Yam tshwm sim: Inverter pib ua rau Modbus kev sib txuas lus ncua sij hawm lossis PROFINET cuam tshuam cuam tshuam.
2. Pulse Noise Interference – Feem ntau Sudden Type of Interference: Siab -Siv sij hawm cuam tshuam yooj yim ua rau cov teeb liab yuam kev lossis txawm tias muaj kev cuam tshuam kev sib txuas lus.
Tej qhov chaw:
Relay / Contactor Kev Ua Haujlwm: Kev sib cuag qhib thiab kaw tsim cov arcs thiab cov hluav taws xob hloov pauv siab;
Lub cev muaj zog pib- nce lossis nres: Rov qab lub zog hluav taws xob ua rau muaj hluav taws xob tawg;
Lightning Induction: Txawm hais tias tsis tshua muaj, nws tuaj yeem qhia ntau txhiab volt pulses raws cov kab hluav taws xob.
Mechanism of Influence: Instantaneous high -amplitude pulses superimposed on signal kab ua rau RS-485 transceivers rau misjudge theem;
Qhov no yog ib qho ntawm cov laj thawj tseem ceeb rau kev nce me ntsis yuam kev hauv kev sib txuas lus digital.
Cov yam ntxwv kuaj pom: Oscilloscopes tuaj yeem ntes microsecond - qib spikes thiab glitches, feem ntau synchronized nrog cov cuab yeej ua haujlwm.
3. Hom-Mod thiab Differential-Mode Interference - Ob Hom Suab nrov nrov ntawm Txoj Kev Ua: Raws li txoj kev nrov nrov tshaj tawm ntawm cov kab teeb liab, nws tau muab faib ua ob pawg, cuam tshuam ncaj qha rau kev ruaj ntseg ntawm cov teeb liab sib txawv.
Common-mode Interference: cuam tshuam qhov hluav taws xob ntawm cov teeb liab kab thiab hauv av. Ntau cov ntsiab lus hauv av tsim muaj qhov sib txawv hauv av; leakage tam sim no coupling. Ib qho - taw tes grounding; siv cov isolators.
Differential-mode Interference (Series-mode): Kev cuam tshuam voltage superimposed ntawm ob lub teeb liab kab. Coupling los ntawm cov kab hluav taws xob uas nyob ib sab; PID hloov suab nrov. Twisted khub; lim capacitors.
Cov Ntsiab Lus Qhia Txog Tus Kheej: Feem ntau-mos cuam tshuam tuaj yeem hloov pauv mus rau qhov sib txawv- hom kev cuam tshuam los ntawm cov kab hluav taws xob tsis sib xws, ua rau cov teeb liab tsis zoo ntxiv.
4. Xov tooj cua Frequency Interference (RFI) – High-Frequency Spatial Coupling Source: Radiated interference from high-frequency wireless devices or digital circuits, easy receive long-line signal loops.
Cov peev txheej: Walkie-talkies, WiFi routers, Bluetooth li; High- zaus induction rhaub, digital moos teeb liab hluav taws xob.
Coupling Mechanism: Unshielded cables ua raws li tau txais cov kav hlau txais xov, demodulating MHz -theem electromagnetic nthwv dej rau hauv qis- suab nrov zaus; Qhov no yog qhov tseem ceeb tshwj xeeb tshaj yog thaum siv cov hlua khi uas tsis muaj kev tiv thaiv.
Tej yam tshwm sim: kev sib txuas lus tsis raug; rov qab tau tshwm sim tom qab cov khoom siv wireless ze ze raug tua.
5. Kev cuam tshuam hauv av - Tsawg-Frequency Disturbances tshwm sim los ntawm qhov tsis zoo hauv av
Thaum cov ntsiab lus sib txawv hauv av muaj nyob rau ntawm ob qhov kawg ntawm kev sib txuas lus nrog cov peev txheej tsis sib xws, ib qho kev nthuav dav yog tsim, tsim kev cuam tshuam.
Cov hauv paus ntsiab lus: Lub txee tswj thiab cov khoom siv hauv teb tau sib cais, ua rau muaj peev xwm sib txawv ntawm ob peb volts; lub shielding txheej ntawm kev sib txuas lus cable yog grounded ntawm ob hnub, tsim ib lub voj kaw.
Cov yam ntxwv cuam tshuam: Superimposed 50Hz lub zog zaus suab nrov tshwm sim raws li qhov hloov pauv hloov pauv hauv qhov ntsuas kub; qhov kev ua yuam kev me ntsis nce nrog qhov kev ncua deb thaum lub sij hawm ntev - kev sib txuas lus nyob deb.
Kev daws: Ua raws li "ib zaug-point grounding", lossis nruab ib lub tshuab cais tawm kom txiav tawm lub voj.
6. Internal Circuit Self-Interference – Suab nrov tsim los ntawm lub system nws tus kheej
Internal Cheebtsam ntawm qhov kub khiav tswj qhov system kuj tuaj yeem ua qhov cuam tshuam.
Cov peev txheej: Siab- zaus oscillations ntawm lub zog hloov pauv hauv qhov ntsuas kub; crosstalk tshwm sim los ntawm kev kaw ntau dhau ntawm cov kab teeb liab digital thiab analog teeb liab; faib capacitance coupling tshwm sim los ntawm siab -ceev teeb liab ntug kev hloov.
Kev cuam tshuam ntau: Feem ntau tshwm sim raws li lub suab nrov ntawm lub sijhawm ruaj khov (xws li kaum tawm kHz); Tej zaum yuav cuam tshuam rau ADC piv txwv qhov tseeb, ua rau muaj kev hloov pauv me ntsis hauv kev nyeem ntawv sensor.
Txoj Kev Tshawb Nrhiav: Siv qhov ze ntawm - kev sojntsuam hauv cheeb tsam txhawm rau nrhiav cov chaw hluav taws xob hauv cheeb tsam ntawm PCB pawg thawj coj saib.
Cov lus qhia ceev ceev rau cov chaw cuam tshuam
|
Interference Source |
Cov yam ntxwv tseem ceeb |
Cov Khoom Siv Hluav Taws Xob |
Kev tiv thaiv zoo |
|
Electromagnetic cuam tshuam (EMI) |
Kev sib txuas lus cuam tshuam, cov ntaub ntawv dhia |
Inverters, servo motors |
Shielded twisted khub cable + hlau conduit |
|
Pulse Noise |
Spikes, CRC yuam kev |
Relays, cua sov hloov |
π- hom lim + magnetic nplhaib |
|
Hom Kev cuam tshuam |
Tsawg-frequency drift, hauv av muaj peev xwm sib txawv |
Multi-point grounding structure |
Ib qho - taw tes grounding + isolator |
|
Xov tooj cua Frequency Interference (RFI) |
Siab - zaus oscillations, irregular me ntsis yuam kev |
Cov khoom siv wireless, siab - cov khoom siv fais fab zaus |
Kev tiv thaiv tag nrho + 360℃connector |
|
Kev cuam tshuam hauv av |
50Hz hloov pauv, ntev -degradation deb |
Distributed grounding system |
Disconnect tej thaj chaw deb shielding grounding |
|
Sab hauv Crosstalk |
Tsau frequency nrov, sampling distortion |
Cov kab hluav taws xob PCB tuab tuab |
3W thaiv txoj cai + orthogonal routing |
Kev tiv thaiv tiag tiag - muaj peev xwm cuam tshuam tau pib nrog kev nkag siab meej txog qhov cuam tshuam. Tsuas yog los ntawm kev txheeb xyuas qhov tseeb thiab txoj hauv kev ntawm txhua hom kev cuam tshuam tuaj yeem tsim kom muaj kev tiv thaiv kev sib koom ua ke nrog kev tiv thaiv, kev cog lus hauv av, thaiv, lim, thiab kev sib cais los xyuas kom lub sijhawm ntev -kev ruaj ntseg ntawm kev sib txuas lus kub kub.
