KUKONZEKERA KWA EMC KWA MOTOR YOLIMA KWAMBIRI YA BRUSHLESS

1. Zomwe zimayambitsa EMC ndi njira zotetezera

M'ma motors othamanga kwambiri, zovuta za EMC nthawi zambiri zimakhala zovuta komanso zovuta za polojekiti yonse, ndipo kukhathamiritsa kwa EMC yonse kumatenga nthawi yambiri. Chifukwa chake, tiyenera kuzindikira molondola zomwe zimayambitsa EMC kupitilira muyeso ndi njira zofananira nazo poyamba.

Kukhathamiritsa kwa EMC makamaka kumayambira mbali zitatu:

• Konzani gwero la kusokoneza

Poyang'anira ma motors othamanga kwambiri, gwero lofunikira kwambiri losokoneza ndikuyendetsa dera lomwe limapangidwa ndi zida zosinthira monga MOS ndi IGBT. Popanda kukhudza magwiridwe antchito a mota yothamanga kwambiri, kuchepetsa kuchuluka kwa chonyamulira cha MCU, kuchepetsa kuthamanga kwa chubu chosinthira, ndikusankha chubu chosinthira ndi magawo oyenera kumatha kuchepetsa kusokoneza kwa EMC.

• Kuchepetsa njira yolumikizirana ya gwero losokoneza

Kukonzanitsa PCBA mayendedwe ndi masanjidwe kungathandize bwino EMC, ndipo kuphatikiza mizere wina ndi mzake kungayambitse kusokoneza kwambiri. Makamaka mizere yolumikizira ma frequency apamwamba, yesetsani kupewa mizere yomwe imapanga malupu ndi mizere yomwe imapanga tinyanga. Ngati ndi kotheka, kuonjezera chitetezo wosanjikiza kuchepetsa kugwirizana.

• Njira zoletsa kusokoneza

Zomwe zimagwiritsidwa ntchito kwambiri pakuwongolera kwa EMC ndi mitundu yosiyanasiyana ya ma inductance ndi ma capacitor, ndipo magawo oyenera amasankhidwa pazosokoneza zosiyanasiyana. Y capacitor ndi common mode inductance ndizosokoneza wamba, ndipo X capacitor ndi yosokoneza mosiyanasiyana. Mphete ya maginito ya inductance imagawidwanso kukhala mphete ya maginito yafupipafupi komanso mphete yocheperako ya maginito, ndipo mitundu iwiri ya inductance iyenera kuwonjezeredwa nthawi imodzi ngati pakufunika.

2. EMC kukhathamiritsa mlandu

Mu kukhathamiritsa kwa EMC kwa 100,000-rpm brushless motor ya kampani yathu, nazi mfundo zazikuluzikulu zomwe ndikuyembekeza zithandiza aliyense.

Kuti injiniyo ifike pa liwiro lalikulu la ma revolution zana limodzi, ma frequency oyambira onyamula amayikidwa ku 40KHZ, yomwe ndi yokwera kawiri kuposa ma mota ena. Pankhaniyi, njira zina zokometsera sizinathe kukonza bwino EMC. Mafupipafupi amachepetsedwa kufika ku 30KHZ ndipo chiwerengero cha nthawi zosinthira MOS chimachepetsedwa ndi 1/3 pasanakhale kusintha kwakukulu. Panthawi imodzimodziyo, zinapezeka kuti Trr (nthawi yobwezeretsanso) ya diode yowonongeka ya MOS imakhala ndi zotsatira pa EMC, ndipo MOS yokhala ndi nthawi yobwezeretsa mofulumira inasankhidwa. Deta yoyesera ili m'chithunzi chomwe chili pansipa. Mphepete mwa 500KHZ~1MHZ yawonjezeka ndi pafupifupi 3dB ndipo mawonekedwe a spike wave asinthidwa:

Chifukwa cha masanjidwe apadera a PCBA, pali mizere iwiri yamphamvu yamagetsi yomwe imayenera kulumikizidwa ndi mizere ina yama siginecha. Pambuyo pa mzere wothamanga kwambiri umasinthidwa kukhala awiri opotoka, kusokonezana pakati pa otsogolera kumakhala kochepa kwambiri. Zomwe zayesedwa zikuwonetsedwa pachithunzichi pansipa, ndipo malire a 24MHZ awonjezeka ndi pafupifupi 3dB:

Pankhaniyi, ma inductors awiri omwe amagwiritsidwa ntchito nthawi zambiri amagwiritsidwa ntchito, imodzi yomwe ndi mphete yamagetsi yotsika kwambiri, yokhala ndi inductance pafupifupi 50mH, yomwe imathandizira kwambiri EMC mumitundu ya 500KHZ ~ 2MHZ. Winayo ndi mphete ya maginito yothamanga kwambiri, yokhala ndi inductance pafupifupi 60uH, yomwe imathandizira kwambiri EMC mumitundu ya 30MHZ ~ 50MHZ.

Deta yoyesera ya mphete ya maginito yotsika pafupipafupi ikuwonetsedwa pachithunzi pansipa, ndipo malire onse amawonjezeka ndi 2dB mumitundu ya 300KHZ~30MHZ:

Deta yoyesera ya mphete ya maginito yothamanga kwambiri ikuwonetsedwa pachithunzi pansipa, ndipo malirewo amachulukitsidwa ndi kupitilira 10dB:

Ndikukhulupirira kuti aliyense atha kusinthana malingaliro ndikukambirana za kukhathamiritsa kwa EMC, ndikupeza yankho labwino kwambiri pakuyesa kosalekeza.