Electromagnetic Compatibility ntawm Hloov Hom Fais Fab
Cov laj thawj rau cov teeb meem electromagnetic compatibility tshwm sim los ntawm kev hloov cov khoom siv hluav taws xob ua haujlwm nyob rau hauv high voltage thiab loj tam sim no switching tej yam kev mob yog heev complex. Nyob rau hauv cov nqe lus ntawm electromagnetic zog ntawm tag nrho cov tshuab, muaj feem ntau yog impedance coupling, kab-rau-kab coupling, hluav taws xob teb coupling, magnetic teb coupling thiab electromagnetic yoj coupling. Common impedance coupling yog feem ntau cov hluav taws xob impedance nruab nrab ntawm qhov thab plaub thiab lub cev thab plaub. Los ntawm qhov impedance no, lub teeb liab thab plaub nkag mus rau hauv lub cev thab plaub. Kab-rau-kab coupling feem ntau yog kev sib txuas ntawm cov xov hlau lossis cov kab PCB uas ua rau muaj kev cuam tshuam qhov hluav taws xob thiab cuam tshuam tam sim no vim yog cov xaim sib txuas. Kev sib txuas hluav taws xob feem ntau yog vim muaj qhov sib txawv ntawm qhov sib txawv, uas ua rau cov hluav taws xob cuam tshuam ua rau thaj chaw sib txuas rau lub cev cuam tshuam. Sib nqus teb coupling feem ntau yog hais txog kev sib txuas ntawm cov khoom siv tsawg zaus sib nqus tsim nyob ze cov kab hluav taws xob siab tam sim no rau kev ua phem rau cov khoom. Electromagnetic field coupling feem ntau yog vim muaj cov hluav taws xob ntau zaus hluav taws xob tsim los ntawm cov hluav taws xob pulsating lossis tam sim no uas tawm sab nraud los ntawm qhov chaw thiab ua rau sib txuas rau lub cev cuam tshuam. Qhov tseeb, txhua txoj kev sib txuas tsis tuaj yeem raug cais nruj me ntsis, tab sis lub hom phiaj sib txawv.
Nyob rau hauv lub switching fais fab mov, lub ntsiab fais fab hloov raj ua hauj lwm nyob rau hauv ib tug high-frequency switching hom ntawm ib tug high voltage. Lub switching voltage thiab switching tam sim no yog ob qho tib si ze rau square waves. Los ntawm kev tsom xam spectrum, nws paub tias lub teeb liab yoj square muaj cov nplua nuj kev txiav txim siab sib haum xeeb. Lub spectrum ntawm qhov kev txiav txim siab siab no tuaj yeem ncav cuag ntau dua 1000 npaug ntawm cov xwm txheej square. Nyob rau tib lub sijhawm, vim tias qhov kev ua haujlwm tsis zoo ntawm cov xau inductance thiab faib cov peev txheej ntawm lub zog hloov hluav taws xob thiab lub zog hloov hluav taws xob tseem ceeb, cov khoom siv hluav taws xob ntau thiab high-voltage peak harmonic oscillations feem ntau tshwm sim thaum muaj ntau zaus qhib lossis tawm. Lub siab dua harmonics generated los ntawm no harmonic oscillation yog nkag mus rau hauv lub sab hauv Circuit Court los ntawm kev faib capacitance ntawm lub hloov raj thiab lub radiator los yog radiated mus rau qhov chaw los ntawm lub radiator thiab transformer. Hloov diodes siv rau rectification thiab freewheeling kuj yog ib qho tseem ceeb ua rau muaj kev cuam tshuam ntau zaus. Vim hais tias lub rectifier thiab freewheeling diodes ua hauj lwm nyob rau hauv ib tug high-frequency switching xeev, lub diode tus lead parasitic inductance, junction capacitance, thiab cov cuam tshuam ntawm rov qab rov qab tam sim no ua rau nws ua hauj lwm ntawm ib tug heev voltage thiab tam sim no hloov tus nqi, thiab tsim high-frequency oscillations. . . Rectifier thiab freewheeling diodes feem ntau yog nyob ze rau ntawm lub hwj chim tso zis kab, thiab cov high-frequency cuam tshuam lawv tsim yog feem ntau yuav kis tau los ntawm DC tso zis kab. Txhawm rau txhim kho cov khoom siv hluav taws xob, hloov cov khoom siv hluav taws xob txais yuav cov khoom siv hluav taws xob kho hluav taws xob. Nyob rau tib lub sijhawm, txhawm rau txhim kho kev ua tau zoo thiab kev ntseeg siab ntawm cov circuits thiab txo cov kev ntxhov siab ntawm cov khoom siv hluav taws xob, cov cuab yeej siv hluav taws xob hloov pauv tau dav siv. Ntawm lawv, xoom voltage, xoom tam sim no lossis xoom voltage / xoom tam sim no hloov tshuab yog siv dav tshaj plaws. Cov tshuab no zoo heev txo cov electromagnetic cuam tshuam los ntawm kev hloov khoom siv. Txawm li cas los xij, feem ntau cov mos-switching lossless absorption circuits siv L thiab C rau kev hloov hluav taws xob, thiab siv unidirectional conductive kev ua tau zoo ntawm diodes kom ua tiav unidirectional zog hloov. Yog li ntawd, cov diodes nyob rau hauv lub resonant Circuit Court dhau los ua ib qho tseem ceeb ntawm electromagnetic cuam tshuam.
Hloov cov khoom siv hluav taws xob feem ntau siv lub zog cia inductors thiab capacitors los ua L thiab C lim circuits los lim cov hom sib txawv thiab hom kev cuam tshuam cov teeb liab. Vim qhov kev faib tawm ntawm cov inductor coil, tus kheej-resonant zaus ntawm inductor coil raug txo, ua rau muaj ntau qhov kev cuam tshuam ntau zaus dhau los ntawm inductor coil thiab nthuav tawm sab nraud raws li AC fais fab kab lossis DC tso tawm kab. . Raws li qhov zaus ntawm cov teeb liab cuam tshuam ntawm lub lim capacitor nce, cov nyhuv ntawm cov hlau lead inductance ua rau cov capacitance thiab filtering nyhuv tsis tu ncua, thiab txawm ua rau lub capacitor tsis hloov, uas kuj yog ib qho kev cuam tshuam ntawm electromagnetic cuam tshuam.
