KUKONZEKEZA KWA EMC KWA MOTO YOPANDA BRUSHLE YOTHAMANGA KWAMBIRI

1. Zomwe zimayambitsa EMC ndi njira zodzitetezera

Mu ma mota opanda burashi othamanga kwambiri, mavuto a EMC nthawi zambiri amakhala cholinga chachikulu komanso chovuta cha polojekiti yonse, ndipo njira yokonzera EMC yonse imatenga nthawi yayitali. Chifukwa chake, tiyenera kuzindikira bwino zomwe zimayambitsa EMC kupitirira muyezo ndi njira zoyenera zokonzera kaye.

Kukonza kwa EMC kumayambira mbali zitatu:

• Sinthani gwero la kusokoneza

Poyang'anira ma mota opanda maburashi othamanga kwambiri, gwero lofunika kwambiri la kusokoneza ndi dera loyendetsa lomwe limapangidwa ndi zida zosinthira monga MOS ndi IGBT. Popanda kukhudza magwiridwe antchito a mota yothamanga kwambiri, kuchepetsa pafupipafupi ya chonyamulira cha MCU, kuchepetsa liwiro la kusintha kwa chubu chosinthira, ndikusankha chubu chosinthira chokhala ndi magawo oyenera kungachepetse bwino kusokoneza kwa EMC.

• Kuchepetsa njira yolumikizirana ya gwero losokoneza

Kukonza njira zoyendetsera ndi kukonza ma PCBA kungathandize kwambiri EMC, ndipo kulumikizana kwa mizere kungayambitse kusokoneza kwakukulu. Makamaka pa mizere ya ma signal yomwe imayenda pafupipafupi, yesetsani kupewa mizere yomwe imapanga ma loops ndi mizere yomwe imapanga ma antenna. Ngati kuli kofunikira, mutha kuwonjezera gawo loteteza kuti muchepetse kulumikizana.

• Njira zoletsera kusokoneza

Chomwe chimagwiritsidwa ntchito kwambiri pakukonza EMC ndi mitundu yosiyanasiyana ya ma inductances ndi ma capacitor, ndipo magawo oyenera amasankhidwa kuti asokonezedwe mosiyanasiyana. Y capacitor ndi common mode inductance ndi za common mode infusion, ndipo X capacitor ndi ya differential mode infusion. Mphete ya maginito ya inductance imagawidwanso kukhala mphete ya maginito ya ma frequency apamwamba ndi mphete ya maginito ya ma frequency otsika, ndipo mitundu iwiri ya ma inductances iyenera kuwonjezeredwa nthawi imodzi pakafunika kutero.

2. Nkhani yokonza EMC

Mu EMC optimization ya injini yopanda maburashi ya 100,000-rpm ya kampani yathu, nazi mfundo zazikulu zomwe ndikukhulupirira kuti zithandiza aliyense.

Kuti mota ifike pa liwiro lalikulu la ma 100,000, ma carrier frequency oyamba amaikidwa pa 40KHZ, omwe ndi okwera kawiri kuposa ma motor ena. Pankhaniyi, njira zina zowongolera sizinathe kukonza bwino EMC. Ma frequency amachepetsedwa kufika pa 30KHZ ndipo nthawi yosinthira ya MOS imachepetsedwa ndi 1/3 isanakhale kusintha kwakukulu. Nthawi yomweyo, zidapezeka kuti Trr (nthawi yobwezeretsa kumbuyo) ya reverse diode ya MOS imakhudza EMC, ndipo MOS yokhala ndi nthawi yobwezeretsa mwachangu idasankhidwa. Deta yoyesera ili monga momwe yasonyezedwera pachithunzi pansipa. Malire a 500KHZ~1MHZ awonjezeka ndi pafupifupi 3dB ndipo mawonekedwe a spike waveform aphwanyidwa:

Chifukwa cha kapangidwe kapadera ka PCBA, pali mizere iwiri yamagetsi yamphamvu yomwe imafunika kulumikizidwa ndi mizere ina yazizindikiro. Pambuyo poti mzere wamagetsi yamphamvu wasinthidwa kukhala awiri opindika, kusokonezana pakati pa ma lead kumakhala kochepa kwambiri. Deta yoyesera ili monga momwe yasonyezedwera pachithunzi pansipa, ndipo malire a 24MHZ awonjezeka ndi pafupifupi 3dB:

Pankhaniyi, ma inductor awiri a common-mode amagwiritsidwa ntchito, imodzi mwa izo ndi mphete ya maginito yotsika, yokhala ndi inductance ya pafupifupi 50mH, yomwe imakweza kwambiri EMC pamlingo wa 500KHZ ~ 2MHZ. Ina ndi mphete ya maginito yokwera kwambiri, yokhala ndi inductance ya pafupifupi 60uH, yomwe imakweza kwambiri EMC pamlingo wa 30MHZ ~ 50MHZ.

Deta yoyesera ya mphete ya maginito yotsika ikuwonetsedwa pachithunzi chili pansipa, ndipo malire onse akuwonjezeka ndi 2dB pakati pa 300KHZ ~ 30MHZ:

Deta yoyesera ya mphete yamaginito ya pafupipafupi kwambiri ikuwonetsedwa pachithunzi chili pansipa, ndipo malire akuwonjezeka ndi oposa 10dB:

Ndikukhulupirira kuti aliyense akhoza kusinthana maganizo ndi kuganizira bwino za kukonza EMC, ndikupeza yankho labwino kwambiri poyesa kosalekeza.