Yuav Ua Li Cas Tsim EMI rau Hloov Cov Khoom Siv Hluav Taws Xob
EMC kev faib tawm thiab cov qauv:
EMC (Electromagnetic Compatibility) yog electromagnetic compatibility, uas suav nrog EMI (Electromagnetic Disturbance) thiab EMS (Electromagnetic Immunity). EMC txhais tau tias yog lub peev xwm ntawm lub cuab yeej lossis lub cev ua haujlwm ib txwm nyob hauv nws qhov chaw electromagnetic tsis ua rau muaj kev cuam tshuam tsis zoo ntawm electromagnetic cuam tshuam rau txhua yam khoom lossis khoom hauv ib puag ncig. EMC yog hu ua electromagnetic compatibility. EMP hais txog electromagnetic pulses.
EMC=EMI ntxiv rau EMS EMI: Electromagnetic cuam tshuam EMS: Electromagnetic compatibility (immunity)
EMI tuaj yeem muab faib ua ob ntu: Kev siv hluav taws xob thiab hluav taws xob,
Kev qhia tshwj xeeb feem ntau tuaj yeem muab faib ua: FCC Tshooj 15J Chav B; CISPR 22 (EN55022, EN61000-3-2, EN61000-3-3) Chav B;
GB IT (GB9254, GB17625) thiab AV (GB13837, GB17625).
FCC xeem zaus yog nyob nruab nrab ntawm 450K-30MHz, thiab CISPR 22 xeem zaus yog nyob nruab nrab ntawm 150K-30MHz. Kev coj ua tuaj yeem kuaj tau siv lub spectrum analyzer, thaum Radiation yuav tsum raug kuaj hauv chav kuaj tshwj xeeb.
EMI hais txog electromagnetic cuam tshuam, uas yog ib feem ntawm EMC. Electronic Magnetic Interference (EMI) yog hais txog electromagnetic cuam tshuam, uas suav nrog conduction, hluav taws xob, tam sim no harmonics, voltage flicker, thiab lwm yam. Electromagnetic cuam tshuam yog tsim los ntawm peb ntu: cuam tshuam qhov chaw, sib txuas channel, thiab receiver, feem ntau hu ua peb lub ntsiab lus ntawm kev cuam tshuam. EMI yog linearly proportional rau tam sim no, thaj tsam ntawm lub voj tam sim no, thiab cov square ntawm zaus, piv txwv li EMI=K * I * S * F2. Kuv yog qhov tam sim no, S yog lub voj voog, F yog qhov zaus, thiab K yog qhov tsis tu ncua ntawm cov khoom siv hauv Circuit Court thiab lwm yam.
Radiated cuam tshuam (30MHz 1GHz) propagates los ntawm qhov chaw thiab ua raws li cov yam ntxwv thiab kev cai ntawm electromagnetic tsis. Tab sis tsis yog txhua lub cuab yeej tuaj yeem cuam tshuam cov hluav taws xob hluav taws xob.
Kev cuam tshuam (150K-30}MHz) yog kev cuam tshuam uas nthuav tawm raws tus neeg xyuas pib. Yog li ntawd, kev nthuav tawm ntawm kev cuam tshuam yuav tsum muaj kev sib txuas ua tiav ntawm qhov cuam tshuam ntawm qhov chaw thiab txais.
EMI hais txog kev cuam tshuam sab nraud electromagnetic ntawm ib yam khoom. Feem ntau, nws muab faib ua ob theem: Chav A thiab Chav B. Chav A yog qib kev lag luam, thiab Chav B yog qib pej xeem. Kev siv pej xeem yog nruj dua li kev siv hauv kev lag luam, raws li kev siv kev lag luam tso cai rau me ntsis hluav taws xob ntau dua. Hais txog kev kuaj hluav taws xob rau tib yam khoom hauv EMI kuaj, ntawm 30-230MHz, Chav B xav kom cov hluav taws xob txwv tsis pub dhau 40dBm, thaum Class A xav kom cov hluav taws xob txwv tsis pub tshaj 50dBm (siv peb meter anechoic chamber ntsuas raws li piv txwv), uas yog kuj xoob. Feem ntau hais lus, CLASSA hais txog lub peev xwm ntawm cov cuab yeej siv txuas ntxiv ua haujlwm ib txwm ua raws li qhov xav tau nyob rau hauv EMI kev sim ntsuas yam tsis muaj kev cuam tshuam los ntawm cov neeg ua haujlwm, Tsis muaj kev ua haujlwm tsis zoo lossis kev ua haujlwm poob qis dua qib kev ua haujlwm tau tso cai.
EMI yog qhov ntsuas hluav taws xob thiab kev ua haujlwm ntawm lub cuab yeej thaum lub sijhawm ua haujlwm. Thaum lub sij hawm kuaj, muaj ob lub siab txwv rau EMI hluav taws xob thiab conduction ntawm lub receiver, sawv cev rau Class A thiab Class B. Yog hais tias qhov kev soj ntsuam waveform tshaj kab ntawm B tab sis ntog hauv qab kab A, cov khoom raug faib raws li Class A. EMS yog kev siv cov cuab yeej ntsuas los cuam tshuam cov khoom lag luam thiab saib seb nws puas tuaj yeem ua haujlwm ib txwm nyob hauv kev cuam tshuam. Yog tias nws ua haujlwm ib txwm lossis tsis muaj kev ua haujlwm degradation tshaj tus qauv, nws raug cais raws li Qib A. Nws tuaj yeem rov pib dua yam tsis muaj qhov ua tau zoo tshaj qhov kev ua haujlwm degradation tau teev tseg hauv tus qauv, thiab raug cais raws li Class B. Yog tias tsis siv neeg rov pib dua, phau ntawv rov pib dua yuav tsum yog qib C, thiab yog tias nws raug tshem tawm, nws yog qib D. Lub teb chaws tus qauv muaj D-theem kev cai, thiab EN tsuas yog muaj A, B, thiab C. EMI yog qhov phem tshaj plaws ntawm qhov txawv ntawm kev ua haujlwm zaus.
