nūhou

Hōʻuluʻulu manaʻo

He mea koʻikoʻi nā Inductors i ka hoʻololi ʻana i nā mea hoʻololi, e like me ka mālama ʻana i ka ikehu a me nā kānana mana. Nui nā ʻano o nā inductors, e like me nā noi like ʻole (mai ka haʻahaʻa haʻahaʻa a hiki i ke kiʻekiʻe kiʻekiʻe), a i ʻole nā ​​​​mea kumu like ʻole e pili ana i nā ʻano o ka inductor, a pēlā aku. ʻO nā inductors i hoʻohana ʻia i ka hoʻololi ʻana i nā mea hoʻololi kiʻekiʻe-frequency mau mea magnetic. Eia nō naʻe, ma muli o nā kumu like ʻole e like me nā mea waiwai, nā kūlana hana (e like me ka volta a me ka manawa), a me ka mahana ambient, ʻokoʻa nā ʻano a me nā manaʻo i hōʻike ʻia. No laila, i ka hoʻolālā kaapuni, i ka hoʻohui ʻana i ke ʻano kumu o ka waiwai inductance, pono e noʻonoʻo ʻia ka pilina ma waena o ka impedance o ka inductor a me ka AC a me ke alapine, ka poho kumu a me nā ʻano saturation o kēia manawa, a me nā mea ʻē aʻe. E hoʻolauna kēia ʻatikala i kekahi mau mea koʻikoʻi inductor koʻikoʻi a me ko lākou mau ʻano, a alakaʻi pū i nā ʻenekini mana e koho i nā inductors maʻamau.

Olelo mua

ʻO ka Inductor kahi mea hoʻokomo electromagnetic, i hana ʻia e ka wili ʻana i kekahi helu o nā coils (coil) ma kahi bobbin a i ʻole ke kumu me kahi uea insulated. Kapa ʻia kēia coil he inductance coil a i ʻole Inductor. E like me ke kumu o ka electromagnetic induction, i ka wā e neʻe ai ka coil a me ka māla magnetic e pili ana i kekahi i kekahi, a i ʻole ka coil e hoʻohua ai i kahi kahua magnetic alternating ma o ke ʻano o kēia manawa, e hoʻokumu ʻia kahi uila i hoʻohuli ʻia e pale aku i ka hoʻololi ʻana o ka māla magnetic mua. a ua kapa ʻia kēia ʻano o ke kāohi ʻana i ka hoʻololi o kēia manawa i ka inductance.

ʻO ke ʻano o ka waiwai inductance e like me ke kumu (1), ʻo ia ka mea like me ka permeability magnetic, ka huinahalike o ka wiliwili hulina N, a me ka like kaapuni makeke cross-sectional wahi Ae, a ua like ia me ka like me ka lōʻihi o ka pōʻai magnetic. . Nui nā ʻano inductance, kūpono kēlā me kēia no nā noi like ʻole; pili ka inductance i ke ʻano, ka nui, ke ʻano wili, ka helu o nā huli, a me ke ʻano o ka mea magnetic waena.

(1)

Ma muli o ke ʻano o ke kumu hao, ʻo ka inductance ka toroidal, E core a me ka pahu; ma ke ʻano o ka mea hao, aia ka nui o ka ceramic core a me ʻelua mau ʻano magnetic palupalu. He ferrite a me ka pauka metala. Ma muli o ke ʻano o ke ʻano a i ʻole ka hoʻopili ʻana, aia nā ʻeha uea, multi-layer, a hoʻoheheʻe ʻia, a ʻo ka ʻeha uea ʻaʻole i pale ʻia a me ka hapalua o ke kolu magnetic Shielded (semi-shielded) a me ka pale (pale), etc.

Ke hana nei ka inductor e like me ke kaapuni pōkole i ke au pololei, a hāʻawi i ka impedance kiʻekiʻe i ke ʻano o kēia manawa. ʻO nā mea hoʻohana maʻamau i nā kaʻapuni ʻo ia ka choking, kānana, hoʻolohe, a me ka mālama ʻana i ka ikehu. I ka hoʻohana ʻana i ka mea hoʻololi hoʻololi, ʻo ka inductor ka mea nui o ka mālama ʻana i ka ikehu, a hoʻokumu i kahi kānana haʻahaʻa haʻahaʻa me ka capacitor hoʻopuka e hōʻemi i ka ripple volta pukana, no laila he mea koʻikoʻi ia i ka hana kānana.

E hoʻolauna kēia ʻatikala i nā ʻano mea koʻikoʻi o nā inductors a me ko lākou mau ʻano, a me kekahi o nā hiʻohiʻona uila o nā inductors, ma ke ʻano he loiloi loiloi koʻikoʻi no ke koho ʻana i nā inductors i ka wā hoʻolālā kaapuni. Ma ka laʻana noiʻi, pehea e helu ai i ka waiwai inductance a pehea e koho ai i kahi inductor maʻamau i loaʻa i ke kālepa e hōʻike ʻia ma o nā laʻana kūpono.

ʻAno mea kumu

ʻO nā inductors i hoʻohana ʻia i ka hoʻololi ʻana i nā mea hoʻololi kiʻekiʻe-frequency mau mea magnetic. ʻO ka mea nui i ke kikowaena e pili nui i nā ʻano o ka inductor, e like me ka impedance a me ka pinepine, ka waiwai inductance a me ka pinepine, a i ʻole nā ​​​​ʻano saturation kumu. E hōʻike ana kēia i ka hoʻohālikelike ʻana o kekahi mau mea hao maʻamau a me ko lākou ʻano saturation ma ke ʻano he kuhikuhi koʻikoʻi no ke koho ʻana i nā inductors mana:

1. ʻO ke kumu seramika

ʻO Ceramic core kekahi o nā mea inductance maʻamau. Hoʻohana nui ʻia ia e hāʻawi i ke ʻano kākoʻo i hoʻohana ʻia i ka wā e wili ai i ka coil. Ua kapa ʻia ʻo ia ʻo "air core inductor". No ka mea, ʻo ke kumu hao i hoʻohana ʻia he mea non-magnetic me kahi haʻahaʻa haʻahaʻa haʻahaʻa haʻahaʻa, paʻa loa ka waiwai inductance i ka pae wela hana. Eia nō naʻe, ma muli o ka mea non-magnetic e like me ka medium, he haʻahaʻa loa ka inductance, ʻaʻole kūpono loa no ka hoʻohana ʻana i nā mea hoʻololi mana.

2. Ferrite

ʻO ke kumu ferrite i hoʻohana ʻia i nā inductors kiʻekiʻe kiʻekiʻe maʻamau he pūhui ferrite i loaʻa i ka nickel zinc (NiZn) a i ʻole manganese zinc (MnZn), he mea ferromagnetic magnetic palupalu me ka coercivity haʻahaʻa. Hōʻike ka Kiʻi 1 i ka pihi hysteresis (BH loop) o kahi kumu magnetic maʻamau. ʻO ka ikaika hoʻoikaika HC o kahi mea magnetic ka mea i kapa ʻia ʻo coercive force, ʻo ia hoʻi i ka wā i hoʻopaneʻe ʻia ai ka mea magnetic i ka saturation magnetic, ua hoʻemi ʻia kona magnetization (magnetization) i ka ʻole. ʻO ka haʻahaʻa coercivity ʻo ia ka haʻahaʻa haʻahaʻa i ka demagnetization a ʻo ia hoʻi ka haʻahaʻa haʻahaʻa o ka hysteresis nalowale.

ʻO ka manganese-zinc a me ka nickel-zinc ferrites he kiʻekiʻe ka pilina pili (μr), ma kahi o 1500-15000 a me 100-1000, kēlā me kēia. ʻO kā lākou kiʻekiʻe magnetic permeability e hoʻokiʻekiʻe i ke kumu hao ma kekahi leo. ʻO ka inductance. Eia nō naʻe, ʻo ka hemahema, ʻo ia ka haʻahaʻa o kēia manawa saturation hiki ke ʻae ʻia, a i ka manawa e hoʻopiha ʻia ai ke kumu hao, e hāʻule loa ka manaʻo magnetic. E nānā i ke Kiʻi 4 no ka emi ʻana o ke ʻano o ka hoʻoheheʻe ʻia o ka ferrite a me ka pauka hao i ka wā i hoʻopiha ʻia ai ke kumu hao. Hoʻohālikelike. Ke hoʻohana ʻia i nā inductors mana, e waiho ʻia kahi ea i loko o ke kaapuni magnetic nui, hiki ke hōʻemi i ka permeability, pale i ka saturation a mālama i ka ikehu hou aʻe; i ka wā e hoʻokomoʻia ai ka ea āpau, hiki ke pili i ka 20- Ma waena o 200. No ka mea hiki i ka resistivity kiʻekiʻe o ka mea pono ke hoʻemi i ka poho i hanaʻia e ka eddy current, ua emi ka poho ma nā alapine kiʻekiʻe, a ua kūpono ia no ka nā mea hoʻololi kiʻekiʻe-frequency, EMI kānana inductors a me ka ikehu mālama inductors o ka mana converters. Ma keʻano o ka hana pinepine, kūpono ka nickel-zinc ferrite no ka hoʻohanaʻana (> 1 MHz), aʻo ka manganese-zinc ferrite kūpono no nā kaha alapine haʻahaʻa (<2 MHz).

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Kiʻi 1. ʻO ka pihi hysteresis o ke kumu magnetic (BR: remanence; BSAT: saturation magnetic flux density)

3. Puka hao kumu

He mau mea ferromagnetic soft-magnetic nā ʻāpana hao pauda. Hana ʻia lākou me ka pauka hao o nā mea like ʻole a i ʻole ka pauka hao wale. Aia i loko o ka formula nā mea non-magnetic me nā ʻāpana ʻāpana like ʻole, no laila ua maʻalahi ka pihi saturation. He toroidal ka nui o ka pauda hao. Hōʻike ke kiʻi 2 i ke kumu hao pauda a me kona ʻike ʻaoʻao.

ʻO nā mea hao pauka maʻamau, ʻo ia ka iron-nickel-molybdenum alloy (MPP), senddust (Sendust), iron-nickel alloy (high flux) a me ka pauka hao (ka pauka hao). Ma muli o nā ʻāpana like ʻole, ʻokoʻa nā ʻano a me nā kumukūʻai, e pili ana i ke koho o nā inductors. E hōʻike ana kēia mau mea i nā ʻano kumu i ʻōlelo ʻia a hoʻohālikelike i ko lākou mau ʻano:

A. hao-nickel-molybdenum alloy (MPP)

Hoʻopau ʻia ka Fe-Ni-Mo alloy e like me MPP, ʻo ia ka pōkole o ka pauka molypermalloy. ʻO ka pili permeability ma kahi o 14-500, a ʻo ka saturation magnetic flux density ma kahi o 7500 Gauss (Gauss), ʻoi aku ka kiʻekiʻe ma mua o ka saturation magnetic flux density o ferrite (ma kahi o 4000-5000 Gauss). Nui i waho. Loaʻa i ka MPP ka poho hao liʻiliʻi loa a loaʻa iā ia ka paʻa wela maikaʻi loa ma waena o nā koina hao pauka. Ke hiki aku nei ka DC o waho i ka ISAT o kēia manawa, e emi mālie ka waiwai inductance me ka ʻole o ka attenuation. ʻOi aku ka maikaʻi o ka hana ʻana o MPP akā ʻoi aku ka nui o ke kumukūʻai, a hoʻohana mau ʻia e like me ka mana inductor a me ka kānana EMI no nā mea hoʻololi mana.

B. Sendust

ʻO ka hao-silicon-aluminum iron core he mea hao hao i haku ʻia me ka hao, silicon, a me ka aluminika, me ka pili magnetic permeability ma kahi o 26 a 125. ʻO ka poho hao ma waena o ka pauka hao a me ka MPP a me ka hao-nickel alloy. . ʻOi aku ka kiʻekiʻe o ka saturation magnetic flux density ma mua o MPP, ma kahi o 10500 Gauss. ʻOi aku ka liʻiliʻi o ka paʻa o ka mahana a me ka saturation i kēia manawa i ka MPP a me ka hao-nickel alloy, akā ʻoi aku ka maikaʻi ma mua o ka pauka hao a me ka ferrite core, a ʻoi aku ka liʻiliʻi o ke kumukūʻai ma mua o ka MPP a me ka hao-nickel alloy. Hoʻohana nui ʻia ia i ka kānana EMI, ka hoʻoponopono ʻana i ka mana o ka mana (PFC) a me nā inductors mana o nā mea hoʻololi mana.

C. hao-nickel alloy

Hana ʻia ke kumu hao-nickel alloy me ka hao a me ka nickel. ʻO ka pili magnetic permeability ma kahi o 14-200. ʻO ka poho hao a me ka paʻa o ka mahana ma waena o MPP a me ka hao-silicon-aluminum. ʻO ke kumu hao-nickel alloy ka mea kiʻekiʻe loa o ka saturation magnetic flux density, ma kahi o 15,000 Gauss, a hiki ke pale aku i nā ʻōlele DC kiʻekiʻe, a ʻoi aku ka maikaʻi o kāna mau hiʻohiʻona DC. Ka laulā noi: Hoʻoponopono i ka mana ikaika, inductance mālama i ka ikehu, inductance kānana, mea hoʻololi kiʻekiʻe o ka flyback converter, etc.

D. Pauka hao

Hana ʻia ka pauka hao me nā ʻāpana pauka maʻemaʻe kiʻekiʻe me nā mea liʻiliʻi liʻiliʻi i hoʻokaʻawale ʻia mai kekahi i kekahi. ʻO ke kaʻina hana hana e loaʻa iā ia kahi ākea ākea. Ma waho aʻe o ke ʻano o ke apo, ʻo ke ʻano o ka pauda hao maʻamau i loaʻa nā ʻano E-type a me nā ʻano stamping. ʻO ka pili magnetic permeability o ka pauka hao ma kahi o 10 a 75, a ʻo ke kiʻekiʻe saturation magnetic flux density ma kahi o 15000 Gauss. Ma waena o nā ʻāpana hao pauka, ʻo ka pauka hao ka nui o ka poho hao akā ʻo ke kumu kūʻai haʻahaʻa loa.

Hōʻike ka Figure 3 i nā pihi BH o PC47 manganese-zinc ferrite i hana ʻia e TDK a me nā pahu hao pauka -52 a me -2 i hana ʻia e MICROMETALS; ʻOi aku ka kiʻekiʻe o ka pilina magnetic o ka manganese-zinc ferrite ma mua o ka pauka hao a hoʻopiha ʻia.

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Kiʻi 3. ʻO ka pihi BH o ka manganese-zinc ferrite a me ka pauka hao o nā mea like ʻole.

I ka hōʻuluʻulu ʻana, ʻokoʻa nā ʻano saturation o ke kumu hao; i ka manawa i oi aku ai ke au o ka saturation, e hā'ule loa ka mana o ka ferrite core, a hiki i ka pauda hao ke emi malie. Hōʻike ke Kiʻi 4 i nā hiʻohiʻona hāʻule o ka pauka hao me ka mana like like a me ka ferrite me kahi ākea ea ma lalo o nā ikaika o ke kahua magnetic. Hoʻomaopopo pū kēia i ka inductance o ka ferrite core, no ka mea, e hāʻule nui ka permeability i ka wā e hoʻopiha ʻia ai ke kumu, e like me ka ʻike ʻia mai ka hoohalike (1), e hāʻule nui ai ka inductance; oiai ka pauda kumu me ka mahele ea kaawale, ka magnetic permeability E emi malie ana ka nui i ka wa i piha ai ka hao, no laila e emi malie ai ka inductance, oia hoi, ua oi aku ka maikai o na hiohiona DC. I ka hoʻohana ʻana i nā mea hoʻololi mana, he mea nui kēia ʻano; inā ʻaʻole maikaʻi ka hiʻohiʻona lohi o ka inductor, piʻi ka inductor i kēia manawa saturation, a ʻo ka hāʻule koke ʻana o ka inductance e hoʻoulu i ke koʻikoʻi o kēia manawa o ke aniani hoʻololi i ka piʻi ʻana, kahi maʻalahi e hōʻino.

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Kiʻi 4. ʻO nā hiʻohiʻona hāʻule o ka pauka hao ferrite a me ka ferrite iron me ka ea ma lalo o ka ikaika o ke kahua magnetic.

ʻO nā hiʻohiʻona uila inductor a me ke ʻano o ka pūʻolo

I ka hoʻolālā ʻana i kahi mea hoʻololi hoʻololi a koho i kahi inductor, ʻo ka waiwai inductance L, impedance Z, AC resistance ACR a me Q waiwai (ʻano kumu), helu IDC a me ISAT o kēia manawa, a me ka poho kumu (core loss) a me nā ʻano uila koʻikoʻi ʻē aʻe. e noonooia. Eia kekahi, e hoʻopilikia ka ʻōnaehana pale o ka inductor i ka nui o ka leakage magnetic, e pili ana i ka EMI. Ma lalo iho nei e kūkākūkā kaʻawale i nā ʻano i ʻōlelo ʻia ma luna e like me ka noʻonoʻo ʻana no ke koho ʻana i nā inductors.

1. Waiwai inductance (L)

ʻO ka waiwai inductance o kahi inductor ka mea koʻikoʻi kumu nui i ka hoʻolālā kaapuni, akā pono e nānā ʻia inā paʻa ka waiwai inductance ma ke alapine hana. Hoʻohana pinepine ʻia ka waiwai nominal o ka inductance ma 100 kHz a i ʻole 1 MHz me ka ʻole o waho DC bias. A no ka hōʻoia ʻana i ka hiki ʻana o ka hana automated mass, ʻo ka hoʻomanawanui o ka inductor maʻamau ± 20% (M) a me ± 30% (N). ʻO ke kiʻi 5 ka pakuhi kikoʻī inductance-frequency o Taiyo Yuden inductor NR4018T220M i ana ʻia me ka mika LCR o Wayne Kerr. E like me ka mea i hōʻike ʻia ma ke kiʻi, ua palahalaha ka pihi waiwai inductance ma mua o 5 MHz, a aneane hiki ke ʻike ʻia ka waiwai inductance ma ke ʻano he mau. Ma ke alapine kiʻekiʻe ma muli o ka resonance i hana ʻia e ka capacitance parasitic a me ka inductance, e hoʻonui ʻia ka waiwai inductance. Ua kapa ʻia kēia alapine resonance ʻo ke alapine resonant ponoʻī (SRF), pono e ʻoi aku ka kiʻekiʻe ma mua o ke alapine hana.

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Kiʻi 5, Taiyo Yuden NR4018T220M inductance-frequency ana kiʻikuhi.

2. Hoʻopili (Z)

E like me ka mea i hōʻike ʻia ma ka Figure 6, hiki ke ʻike ʻia ke kiʻi impedance mai ka hana ʻana o ka inductance ma nā alapine like ʻole. ʻO ka impedance o ka inductor ua like like ia me ke alapine (Z=2πfL), no laila ʻoi aku ka kiʻekiʻe o ke alapine, ʻoi aku ka nui o ka reactance ma mua o ke kūpaʻa AC, no laila ke ʻano o ka impedance e like me ka inductance maʻemaʻe (ʻo 90˚ ka pae). Ma nā alapine kiʻekiʻe, ma muli o ka hopena capacitance parasitic, hiki ke ʻike ʻia ke ʻano o ka impedance ponoʻī. Ma hope o kēia manawa, hāʻule ka impedance a lilo i capacitive, a hoʻololi mālie ka māhele i -90 ˚.

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3. Waiwai Q a me ke kū'ē AC (ACR)

ʻO ka waiwai Q ma ka wehewehe o ka inductance ka lākiō o ka reactance i ke kū'ē, ʻo ia hoʻi, ka lakio o ka ʻāpana noʻonoʻo i ka ʻāpana maoli o ka impedance, e like me ke ʻano (2).

(2)

Ma kahi o XL ka reactance o ka inductor, a ʻo RL ke kūpaʻa AC o ka inductor.

Ma ke alapine haʻahaʻa haʻahaʻa, ʻoi aku ka nui o ke kūpaʻa AC ma mua o ka reactance i hana ʻia e ka inductance, no laila he haʻahaʻa loa kona waiwai Q; i ka piʻi ʻana o ke alapine, ʻoi aku ka nui a me ka nui o ka reactance (e pili ana i 2πfL), ʻoiai inā ʻo ke kū'ē ʻana ma muli o ka hopena o ka ʻili (ka hopena o ka ʻili) a me ka hopena (kokoke) ka hopena. ; i ka hoʻokokoke ʻana iā SRF, ua hoʻopau mālie ʻia ka reactance inductive e ka reactance capacitive, a liʻiliʻi liʻiliʻi ka waiwai Q; ke lilo ka SRF i zero, no ka mea, ua like loa ka reactance inductive a me ka reactance capacitive. Hōʻike ke kiʻi 7 i ka pilina ma waena o ka waiwai Q a me ka pinepine o NR4018T220M, a ʻo ka pilina ma ke ʻano o ka bele hoʻohuli.

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Kiʻi 7. ʻO ka pilina ma waena o ka waiwai Q a me ke alapine o Taiyo Yuden inductor NR4018T220M

I ka hoʻohana pinepine ʻana o ka inductance, ʻoi aku ka kiʻekiʻe o ka waiwai Q, ʻoi aku ka maikaʻi; 'o ia ho'i, 'oi aku ka nui o kona reactance ma mua o ke kū'ē AC. Ma ka ʻōlelo maʻamau, ʻoi aku ka maikaʻi o ka waiwai Q ma luna o 40, ʻo ia hoʻi ka maikaʻi o ka inductor. Eia naʻe, ma ka maʻamau i ka piʻi ʻana o ka bias DC, e emi ana ka waiwai inductance a e emi pū ka waiwai Q. Inā hoʻohana ʻia ka uea enameled flat a i ʻole multi-strand enameled wire, hiki ke hoʻemi ʻia ka hopena o ka ʻili, ʻo ia hoʻi, ke kūpaʻa AC, a hiki ke hoʻonui ʻia ka waiwai Q o ka inductor.

ʻO ka DC resistance DCR ka mea maʻamau i manaʻo ʻia e like me ke kūpaʻa DC o ka uea keleawe, a hiki ke helu ʻia ke kūpaʻa e like me ke anawaena uea a me ka lōʻihi. Eia naʻe, e hoʻohana ka hapa nui o nā mea hoʻokomo haʻahaʻa SMD i kēia manawa i ka hoʻoheheʻe ultrasonic e hana i ka ʻāpana keleawe o ka SMD ma ka pahu wili. Eia naʻe, no ka mea, ʻaʻole lōʻihi ka lōʻihi o ka uea keleawe a ʻaʻole kiʻekiʻe ke kumukūʻai kūʻē, ʻo ke kūpaʻa kuʻi ʻana e helu pinepine i ka hapa nui o ke kūpaʻa DC holoʻokoʻa. Ke lawe nei i ka uea-eha SMD inductor CLF6045NIT-1R5N ma ke ʻano he laʻana, ʻo 14.6mΩ ke kūpaʻa DC i ana ʻia, a ʻo ke kūpaʻa DC i helu ʻia ma muli o ke anawaena uea a me ka lōʻihi he 12.1mΩ. Hōʻike nā hualoaʻa e pili ana kēia kūpaʻa kuʻi ʻana ma kahi o 17% o ke kūpaʻa DC holoʻokoʻa.

ʻO ke kūpaʻa AC ACR ka hopena ʻili a me ka hopena pili, e hoʻonui ai ka ACR me ka pinepine; i ka hoʻohana ʻana i ka inductance maʻamau, no ka mea ʻoi aku ka haʻahaʻa o ka ʻāpana AC ma mua o ka ʻāpana DC, ʻaʻole maopopo ka mana o ka ACR; akā, ma ka haawe māmā, No ka mea, ua ho'ēmiʻia ka mea DC,ʻaʻole hiki ke mālamaʻia ka poho i hanaʻia e ACR. ʻO ka hopena o ka ʻili, ʻo ia hoʻi, ma lalo o nā kūlana AC, ʻaʻole kūlike ka māhele ʻana o kēia manawa i loko o ka conductor a paʻa i ka ʻili o ka uea, e hopena i ka hoʻemi ʻana i ka ʻāpana cross-sectional uea like, e hoʻonui ai i ke kūpaʻa like o ka uea me alapine. Eia kekahi, ma ka wili uea, e hoʻohui ʻia nā uea pili i ka hoʻohui a me ka unuhi ʻana o nā māla magnetic ma muli o ke ʻano o kēia manawa, no laila e paʻa ke ʻano ma luna o ka ʻili e pili ana i ka uea (a i ʻole ka ʻili mamao loa, e pili ana i ke kuhikuhi o ke au. ), ka mea hoʻi e hoʻopili ai i ka uea like. ʻO ke ʻano o ka emi ʻana o ka wahi a me ka piʻi ʻana o ke kūpaʻa like, ʻo ia ka mea i kapa ʻia ʻo ka hopena pili; i ka noi inductance o ka multilayer winding, ʻoi aku ka maopopo o ka hopena pili.

8

Hōʻike ka Figure 8 i ka pilina ma waena o ke kūpaʻa AC a me ke alapine o ka uea-ʻeha SMD inductor NR4018T220M. Ma ke alapine o 1kHz, ʻo ke kū'ē ma kahi o 360mΩ; ma 100kHz, piʻi ke kū'ē i 775mΩ; ma 10MHz, kokoke ka waiwai kū'ē i 160Ω. Ke koho ʻana i ka poho keleawe, pono e noʻonoʻo ka helu ʻana i ka ACR i hoʻokumu ʻia e ka ʻili a me nā hopena pili kokoke, a hoʻololi i ke ʻano (3).

4. ʻO kēia manawa (ISAT)

ʻO ka ISAT saturation i kēia manawa ka mea maʻamau i hōʻailona ʻia i ka wā i hoʻemi ʻia ka waiwai inductance e like me 10%, 30%, a i ʻole 40%. No ka ferrite air-gap, no ka mea wikiwiki loa kona ʻano saturation o kēia manawa, ʻaʻohe ʻokoʻa nui ma waena o 10% a me 40%. E nānā i ke Kiʻi 4. Eia naʻe, inā ʻo ia ka pauka hao (e like me ka inductor i hoʻopaʻa ʻia), ʻoi aku ka mālie o ka pihi saturation, e like me ka mea i hōʻike ʻia ma ke Kiʻi 9, ʻo ke ʻano o kēia manawa ma 10% a i ʻole 40% o ka attenuation inductance he nui. ʻokoʻa, no laila e kūkākūkā kaʻawale ʻia ka waiwai o kēia manawa no nā ʻano ʻelua o nā koina hao e like me kēia.

No ka ferrite ea-gap, kūpono ke hoʻohana ʻana i ka ISAT ma ke ʻano he palena kiʻekiʻe o ka manawa inductor kiʻekiʻe no nā noi kaapuni. Eia nō naʻe, inā ʻo ia ka pauka hao, ma muli o ke ʻano o ka saturation lohi, ʻaʻohe pilikia inā ʻoi aku ka nui o kēia manawa o ke kaapuni noi ma mua o ISAT. No laila, kūpono loa kēia ʻano hao no ka hoʻololi ʻana i nā noi hoʻololi. Ma lalo o ke kaumaha kaumaha, ʻoiai he haʻahaʻa ka waiwai inductance o ka inductor, e like me ka mea i hōʻike ʻia ma ka Figure 9, he kiʻekiʻe ke kumu ripple o kēia manawa, akā ʻoi aku ka kiʻekiʻe o ka capacitor o kēia manawa, no laila ʻaʻole ia he pilikia. Ma lalo o ka haʻahaʻa māmā, ʻoi aku ka nui o ka inductance waiwai o ka inductor, e kōkua ana e hōʻemi i ka ripple o kēia manawa o ka inductor, a laila e hōʻemi ana i ka poho hao. Hoʻohālikelike ke Kiʻi 9 i ka pihi saturation o kēia manawa o ka ferrite ʻeha o TDK SLF7055T1R5N a me ka hoʻoheheʻe ʻana i ka pauka hao SPM6530T1R5M ma lalo o ka waiwai nominal like o ka inductance.

9

Kiʻi 9. ʻO ka piko o kēia manawa o ka ferrite ʻeha a me ka pauka hao i hoʻopaʻa ʻia ma lalo o ka waiwai nominal like o ka inductance.

5. Ua helu ʻia i kēia manawa (IDC)

ʻO ka waiwai IDC ka DC bias ke piʻi ka mahana inductor i Tr˚C. Hōʻike pū nā kikoʻī i kāna waiwai kūʻē DC RDC ma 20˚C. E like me ka coefficient mahana o ka uea keleawe ma kahi o 3,930 ppm, ke piʻi ka mahana o Tr, ʻo kona waiwai kūʻē ʻo RDC_Tr = RDC (1+0.00393Tr), a ʻo kona hoʻohana mana ʻo PCU = I2DCxRDC. Hoʻopau ʻia kēia poho keleawe ma ka ʻili o ka inductor, a hiki ke helu ʻia ke kūpaʻa wela ΘTH o ka inductor:

(2)

Hōʻike ka papa 2 i ka pepa ʻikepili o ka moʻo TDK VLS6045EX (6.0 × 6.0 × 4.5mm), a helu i ke kūpaʻa wela i ka piʻi ʻana o ka wela o 40˚C. ʻIke loa, no nā mea hoʻokomo o ka moʻo like a me ka nui, ʻaneʻane like ke kūpaʻa wela i helu ʻia ma muli o ka ʻāpana wela o ka ʻili; i nā huaʻōlelo ʻē aʻe, hiki ke koho ʻia ka IDC o kēia manawa o nā inductors like ʻole. ʻOkoʻa moʻo (packages) o inductors loaʻa nā thermal resistances. Hoʻohālikelike ka Papa 3 i ka pale wela o nā inductors o TDK VLS6045EX moʻo (semi-pale) a me SPM6530 series (hoʻoheheʻe). ʻOi aku ka nui o ke kūpaʻa wela, ʻoi aku ka kiʻekiʻe o ka piʻi ʻana o ka mahana i ka wā e kahe ai ka inductance ma o ka haʻawe o kēia manawa; i ole ia, o ka lalo.

(2)

Papa 2. Ke kū'ē wela o VLS6045EX series inductors i ka pi'i wela o 40˚C

Hiki ke ʻike ʻia mai ka Papa 3 inā like ka nui o nā inductors, ʻoi aku ka haʻahaʻa o ke kūpaʻa wela o nā inductors stamped, ʻo ia hoʻi, ʻoi aku ka maikaʻi o ka wela.

(3)

Papa 3. Ka hoohalike ana o ke ku'e wela o na mea hookomo puolo like ole.

6. Ke poho kumu

ʻO ka poho kumu, i kapa ʻia ʻo ka hao hao, ke kumu nui ʻia e ka eddy current loss a me ka hysteresis loss. ʻO ka nui o ka poho o kēia manawa e pili ana i ka maʻalahi o ka mea kumu e "hana"; inā kiʻekiʻe ka conductivity, ʻo ia hoʻi, he haʻahaʻa ke kūʻē, he kiʻekiʻe ka poho o ka eddy, a inā he kiʻekiʻe ka pale o ka ferrite, he haʻahaʻa loa ka poho o kēia manawa. Ua pili pū ka poho o Eddy i kēia manawa me ka pinepine. ʻO ke kiʻekiʻe o ke alapine, ʻoi aku ka nui o ka poho o kēia manawa. No laila, e hoʻoholo ka mea kumu i ka alapine hana kūpono o ke kumu. ʻO ka ʻōlelo maʻamau, hiki i ke alapine hana o ka pauka hao ke hiki i 1MHz, a hiki i ke alapine hana o ka ferrite ke hiki i 10MHz. Inā ʻoi aku ka nui o ka hana ma mua o kēia alapine, e piʻi koke ka nalowale o kēia manawa a e piʻi pū ka wela o ka hao. Eia nō naʻe, me ka hoʻomohala wikiwiki ʻana o nā mea hao hao, ʻo nā cores hao me nā alapine hana kiʻekiʻe e pono ma kahi o ke kihi.

ʻO kekahi poho hao, ʻo ia ka poho hysteresis, i kūlike me ka ʻāpana i hoʻopaʻa ʻia e ka hysteresis curve, e pili ana i ka amplitude swing o ka ʻāpana AC o kēia manawa; ʻoi aku ka nui o ka swing AC, ʻoi aku ka nui o ka nalowale o ka hysteresis.

Ma ke kaapuni like o kahi inductor, hoʻohana pinepine ʻia kahi resistor i hoʻopili ʻia me ka inductor e hōʻike i ka poho hao. Ke like ka alapine me SRF, hoʻopau ka reactance inductive a me ka reactance capacitive, a ʻo ka reactance like ʻole. I kēia manawa, ua like ka impedance o ka inductor me ke kūpaʻa poho hao ma ke ʻano me ke kūpaʻa wili, a ʻoi aku ka nui o ke kūpaʻa o ka hao ma mua o ke kūpaʻa wili, no laila ua like ka impedance ma SRF me ke kūpaʻa poho hao. ʻO ka lawe ʻana i kahi inductor haʻahaʻa haʻahaʻa ma ke ʻano he laʻana, ʻo kona pale ʻana i ka hao ma kahi o 20kΩ. Inā manaʻo ʻia ʻo 5V ka volta waiwai kūpono ma nā ʻaoʻao ʻelua o ka inductor, ʻo kona poho hao ma kahi o 1.25mW, ʻo ia hoʻi e hōʻike ana i ka nui o ke kūpaʻa hao, ʻoi aku ka maikaʻi.

7. Ka hale pale

ʻO ke ʻano o ka hoʻopili ʻana o nā inductors ferrite me ka pale ʻole, semi-pale me ka lei magnetic, a me ka pale, a he nui ka ea i loko o kekahi o lākou. ʻIke loa, e loaʻa i ka leaka ea ka leakage, a i ka hihia ʻoi loa, e hoʻopilikia ia i nā kaapuni hōʻailona liʻiliʻi e hoʻopuni ana, a inā aia kahi mea magnetic kokoke, e hoʻololi pū ʻia kona inductance. ʻO kahi hoʻolālā hoʻopili ʻē aʻe he inductor pauka hao. No ka mea, ʻaʻohe wahi āpau i loko o ka inductor a paʻa ka ʻōnaehana wili, he liʻiliʻi ka pilikia o ka dissipation field magnetic. ʻO ka helu 10 ka hoʻohana ʻana i ka hana FFT o ka RTO 1004 oscilloscope e ana i ka nui o ka leakage magnetic field ma 3mm ma luna a ma ka ʻaoʻao o ka inductor stamped. Papa 4 papa inoa i ka hoʻohālikelike o ka leakage mākēneki kahua o nā ʻokoʻa inductor hoʻolālā. Hiki ke ʻike ʻia i nā inductors pale ʻole i ka leakage magnetic koʻikoʻi; ʻO nā inductors i hoʻopaʻa ʻia i ka liʻiliʻi liʻiliʻi liʻiliʻi, e hōʻike ana i ka hopena pale pale magnetic maikaʻi loa. . ʻO ka ʻokoʻa o ka nui o ka leakage magnetic field o nā inductors o kēia mau hale ʻelua ma kahi o 14dB, ʻo ia ka mea kokoke i 5 mau manawa.

10

Kiʻi 10. ʻO ka nui o ka leakage magnetic field i ana ʻia ma 3mm ma luna a ma ka ʻaoʻao o ka inductor i hoʻopaʻa ʻia.

(4)

Papa 4. Ka hoohalike ana o ka leakage magnetic field o na mea hookomo o ka hale waihona

8. hoʻopili

I kekahi mau noi, i kekahi manawa he nui nā pūʻulu o nā mea hoʻololi DC ma ka PCB, i hoʻonohonoho pinepine ʻia ma kahi kokoke i kekahi, a ua hoʻonohonoho pū ʻia kā lākou mau inductors e pili ana i kekahi. Inā ʻoe e hoʻohana i kahi ʻano pale pale ʻole a i ʻole semi-pale me ka magnetic glue Hiki ke hoʻohui ʻia nā Inductors me kekahi i kekahi e hana i ka hoʻopili EMI. No laila, i ka wā e kau ai i ka inductor, pono ia e hōʻailona i ka polarity o ka inductor ma mua, a hoʻohui i ka wahi hoʻomaka a me ka wili o ka papa o loko o ka inductor i ka uila hoʻololi o ka mea hoʻololi, e like me ka VSW o kahi mea hoʻololi kālā, oia ka lae oni. Hoʻopili ʻia ka pahu puka i ka capacitor hoʻopuka, ʻo ia ke kiko static; ka uea keleawe wili no laila e hana i kekahi degere o ka uila kahua pale. I ka hoʻonohonoho wili o ka multiplexer, ʻo ka hoʻoponopono ʻana i ka polarity o ka inductance e kōkua i ka hoʻoponopono ʻana i ka nui o ka inductance like a pale i nā pilikia EMI i manaʻo ʻole ʻia.

Nā noi:

Ua kūkākūkā ka mokuna mua i ka mea kumu, ka hoʻonohonoho pūʻolo, a me nā ʻano uila koʻikoʻi o ka inductor. E wehewehe kēia mokuna pehea e koho ai i ka waiwai inductance kūpono o ka buck converter a me nā noʻonoʻo no ke koho ʻana i kahi inductor hiki ke kūʻai ʻia.

E like me ka mea i hōʻike ʻia ma ka hoohalike (5), ʻo ka waiwai inductor a me ke alapine hoʻololi o ka mea hoʻololi e hoʻopili i ka inductor ripple current (ΔiL). E kahe ana ke au ripple inductor ma o ka capacitor output a pili i ke au ripple o ka capacitor output. No laila, e hoʻopilikia ia i ke koho ʻana i ka capacitor puka a pili hou i ka nui ripple o ka volta puka. Eia kekahi, e pili pū ka waiwai inductance a me ka waiwai capacitance i ka hoʻolālā manaʻo o ka ʻōnaehana a me ka pane ikaika o ka ukana. ʻO ke koho ʻana i kahi waiwai inductance ʻoi aku ka liʻiliʻi o ke koʻikoʻi o kēia manawa ma ka capacitor, a he mea maikaʻi hoʻi ia e hōʻemi i ka ripple voltage puka a hiki ke mālama i ka ikehu hou aʻe. Eia nō naʻe, ʻoi aku ka nui o ka inductance waiwai e hōʻike ana i ka leo nui, ʻo ia hoʻi, ke kumukūʻai kiʻekiʻe. No laila, i ka hoʻolālā ʻana i ka mea hoʻololi, he mea nui ka hoʻolālā ʻana o ka waiwai inductance.

(5)

Hiki ke ʻike ʻia ma ke ʻano (5) inā ʻoi aku ka nui o ka ʻokoʻa ma waena o ka volta hoʻokomo a me ka puʻuwai hoʻopuka, e ʻoi aku ka nui o ke au inductor ripple, ʻo ia ke kūlana ʻino loa o ka hoʻolālā inductor. Hoʻohui pū ʻia me nā loiloi inductive ʻē aʻe, pono ke koho ʻia ka wahi hoʻolālā inductance o ka mea hoʻololi i lalo ma lalo o nā kūlana o ka volta komo kiʻekiʻe a me ka ukana piha.

I ka hoʻolālā ʻana i ka waiwai inductance, pono ia e hana i kahi kālepa ma waena o ka ripple inductor current a me ka nui o ka inductor, a ua wehewehe ʻia ka ripple current factor (ripple current factor; γ) e like me ka formula (6).

（6）

Ke hoʻololi nei i ke ʻano (6) i ke kumu (5), hiki ke hōʻike ʻia ka waiwai inductance ma ke ʻano he kumu (7).

（7）

Wahi a ke kumu (7), ke ʻoi aku ka nui o ka ʻokoʻa ma waena o ka volter input a me ka puka makani, hiki ke koho nui ʻia ka waiwai γ; akā, inā kokoke ka volta hoʻokomo a me ka hoʻopuka ʻana, pono e liʻiliʻi ka hoʻolālā waiwai γ. I mea e koho ai ma waena o ka inductor ripple i kēia manawa a me ka nui, e like me ka waiwai o ka hoʻolālā kuʻuna, ʻo γ ka mea maʻamau 0.2 a 0.5. Ke lawe nei kēia i ka RT7276 ma ke ʻano he laʻana e hōʻike i ka helu ʻana o ka inductance a me ke koho ʻana i nā inductors i loaʻa i ke kālepa.

Laʻana hoʻolālā: Hoʻolālā ʻia me ka RT7276 holomua mau i ka manawa (Advanced Constant On-Time; ACOTTM) hoʻololi hoʻoponopono i lalo, ʻo kona alapine hoʻololi ʻo 700 kHz, ʻo 4.5V a hiki i 18V ka uila hoʻokomo, a ʻo 1.05V ka uila puka. . ʻO 3A ka ukana piha o kēia manawa. E like me ka mea i ʻōlelo ʻia ma luna nei, pono e hoʻolālā ʻia ka waiwai o ka inductance ma lalo o nā kūlana o ka volta komo kiʻekiʻe o 18V a me ka ukana piha o 3A, lawe ʻia ka waiwai o γ e like me 0.35, a ua hoʻololi ʻia ka waiwai i luna i ka hoohalike (7), ka inductance. waiwai ʻo

E hoʻohana i kahi inductor me kahi waiwai inductance nominal maʻamau o 1.5 µH. E hoʻololi i ke kumu (5) no ka helu ʻana i ke au o ka ripple inductor penei.

No laila, ʻo ke kiʻekiʻe o kēia manawa o ka inductor

A ʻo ka waiwai kūpono o ka inductor current (IRMS).

Ma muli o ka liʻiliʻi o ka ʻāpana ripple inductor, ʻo ka waiwai kūpono o ka inductor i kēia manawa ʻo ia ka mea nui o DC, a ua hoʻohana ʻia kēia waiwai kūpono i kumu no ke koho ʻana i ka IDC i koho ʻia i kēia manawa. Me ka 80% derating (derating) hoʻolālā, nā koi inductance:

L = 1.5 µH (100 kHz), IDC = 3.77 A, ISAT = 4.34 A

Papa 5 ka papa inoa o na inductors i loaʻa o nā moʻo like ʻole o TDK, like ka nui akā ʻokoʻa ka hoʻolālā pūʻolo. Hiki ke ʻike ʻia mai ka papa ʻaina ka nui o ka saturation a me ka helu o kēia manawa o ka inductor stamped (SPM6530T-1R5M), a he liʻiliʻi ke kūpaʻa wela a maikaʻi ka dissipation wela. Eia kekahi, e like me ka kūkākūkā ma ka mokuna mua, ʻo ka mea nui o ka inductor i hoʻopaʻa ʻia ʻo ia ka pauka hao, no laila ua hoʻohālikelike ʻia me ka ferrite core o ka semi-shielded (VLS6045EX-1R5N) a me ka pale (SLF7055T-1R5N) inductors. me ka pulupulu magnetic. , Loaʻa nā hiʻohiʻona DC maikaʻi. Hōʻike ka Figure 11 i ka hoʻohālikelike kūpono o nā inductors like ʻole i hoʻopili ʻia i ka RT7276 holomua mau i ka manawa hoʻoponopono hoʻoponopono hoʻololi i lalo. Hōʻike nā hopena ʻaʻole koʻikoʻi ka ʻokoʻa kūpono ma waena o nā ʻekolu. Inā ʻoe e noʻonoʻo i ka wela wela, nā hiʻohiʻona DC a me nā pilikia hoʻohemo ʻana o ke kahua magnetic, pono e hoʻohana i nā inductors SPM6530T-1R5M.

（5）

Papa 5. Hoʻohālikelike o nā inductances o nā moʻo like ʻole o TDK

11

Kiʻi 11. Hoʻohālikelike i ka pono o ka mea hoʻololi me nā inductors like ʻole

Inā koho ʻoe i ka hoʻolālā ʻāpana like a me ka waiwai inductance, akā ʻoi aku ka liʻiliʻi o nā inductors, e like me SPM4015T-1R5M (4.4 × 4.1 × 1.5mm), ʻoiai he liʻiliʻi kona nui, akā ʻo ka DC resistance RDC (44.5mΩ) a me ka thermal resistance ΘTH ( 51˚C) /W) Nui aʻe. No nā mea hoʻololi o nā kikoʻī like, ʻo ka waiwai kūpono o ka manawa i ʻae ʻia e ka inductor ua like nō hoʻi. ʻIke loa, e hōʻemi ke kūʻē DC i ka pono ma lalo o ka ukana kaumaha. Eia kekahi, ʻo ke kūpaʻa wela nui ke ʻano o ka hoʻoheheʻe wela maikaʻi ʻole. No laila, i ke koho ʻana i kahi inductor, ʻaʻole pono e noʻonoʻo i nā pono o ka liʻiliʻi o ka nui, akā e loiloi pū kekahi i kona mau hemahema.

I ka hopena

ʻO ka Inductance kekahi o nā ʻāpana passive maʻamau i ka hoʻololi ʻana i nā mea hoʻololi mana, hiki ke hoʻohana ʻia no ka mālama ʻana i ka ikehu a me ka kānana. Eia nō naʻe, i ka hoʻolālā kaapuni, ʻaʻole wale ka waiwai inductance e pono e nānā ʻia, akā nā ʻāpana ʻē aʻe e pili ana i ke kūpaʻa AC a me ka waiwai Q, ka ʻae ʻana i kēia manawa, ka saturation iron core, a me ka hoʻolālā ʻāpana, a me nā mea ʻē aʻe. e noʻonoʻo ʻia i ke koho ʻana i kahi inductor. . Hoʻopili pinepine ʻia kēia mau ʻāpana i ka mea kumu, ke kaʻina hana, a me ka nui a me ke kumukūʻai. No laila, hōʻike kēia ʻatikala i nā hiʻohiʻona o nā mea hao hao like ʻole a pehea e koho ai i kahi inductance kūpono ma ke ʻano he kuhikuhi no ka hoʻolālā lako mana.