Indlela yokuphucula uyilo lwe-transformer kwi-PoE Power Supply

Indlela yokuphucula uyilo lwe-transformer kwi-PoE Power Supply

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Amandla phezu kwe-Ethernet - Itekhnoloji yobonelelo lwamandla ibhekisa kwindlela i-PSE (Power souring Equipment) yokudlulisela amandla kwi-PD (Power Device) ngeentambo zenethiwekhi. Iinkqubo eziqhelekileyo, umzekelo, zithatha i-PSE switch njengesiseko, ziqhagamshela izixhobo ezininzi ze-PD ezifana ne-Access Point, i-IP Phone kunye ne-IP Camera ngeentambo zenethiwekhi, kwaye i-PSE igqibezela ukuhanjiswa kwesignali kunye namandla kwi-PD.

Umbane wePoE unezi nzuzo zilandelayo:

• Ukufakela nokwandisa okulula: Isignali kunye namandla zidluliselwa ngeentambo zenethiwekhi, kwaye akukho mfuneko yojongano lwamandla olujikeleze isixhobo sePD

• Ulawulo olukude: Isixhobo esinye se-PSE sinikezela ngombane kwizixhobo ezininzi ze-PD zolawulo lwamandla olukude

• Ixabiso eliphantsi: umgca wesignali kunye nomgca wombane zidityaniswe zibe yinto enye, kungabikho intambo yombane, ngoko ke intambo yothungelwano ayisiyo nje kuphela umthwali wothungelwano lwesignali, kodwa ikwathatha indima yothungelwano lwamandla, ngoko ke iindleko zocingo ziyancitshiswa.

• Ukuhambelana okuhle: iprotokholi ye-PoE edibeneyo iqinisekisa ukuba izixhobo ze-PD zinokuhambelana nayo nayiphi na i-PSE kwihlabathi liphela.

Ngokuphathelele uyilo lwesekethe, i-PSE ekhohlo ithumela i-DC 44-57V kwi-PD, ngelixa i-PD esekunene iguqula umbane uye kumbane ofunekayo ngesekethe esezantsi. I-PSE kunye ne-PD ziqhagamshelwe nge-port ye-RJ45 kunye nentambo ye-twisted pair eyi-100m.

Ngokweemeko ezahlukeneyo zokusetyenziswa kwamandla, imigangatho yombane ye-IEEE 802.3AF, IEEE 802.3AT kunye ne-IEEE 802.3BT Ethernet ipapashwe yi-IEEE. Ngokukodwa, umgangatho we-IEEE 802.3BT wakhutshwa ngo-2019, nto leyo ephucula kakhulu amandla ombane we-PoE. I-PSE inika amandla e-90W, kwaye i-PD ifumana i-71W emva kweemitha ezili-100 zentambo yenethiwekhi. Eli nqanaba lamandla leklasi yesi-8 lisetyenziswa kakhulu kwinkqubo yombane yezikhululo ezincinci zesiseko. Ukongeza, imigangatho ye-802.3BT ihambelana ngasemva nemigangatho ye-802.3AF kunye ne-802.3AT. Xa i-802.3BT PD iqhagamshelwe kwi-802.3AF kunye ne-802.3AT PSE enamandla aphantsi, iya kusebenza kwimeko yamandla aphantsi, oko kukuthi, "ewohlokileyo".

Kule nkqubo, i-PD enamandla aphantsi iqhagamshelwe kwi-PSE enamandla aphezulu, kwaye akukho monakalo wenzekayo kwisixhobo. Le nkqubo ilandelayo yokuxhawulana iyenzeka ikakhulu xa i-PSE inika i-PD amandla:

Uyilo lweSicelo soNikezelo lwaMandla

I-DC/DC inezicwangciso ezizimeleyo nezingezozodwa. Kwi-solid POE power supply, yahlulwe yaba zii-forward kunye nee-flyback topology, kuquka i-PSR (primary side feedback) kunye ne-SSR (secondary side feedback). Ezi topology zilandelayo ziyahlalutywa:

Kwisakhiwo sesekethe sezixhobo zePD, iiparameter ezintathu zichaphazeleka kakhulu: ubungakanani, ukusebenza kakuhle kunye ne-EMC. Emva koko ungadibanisa njani iimfuno zezixhobo zePD kunye neemfuno zoyilo lwetransformer?

Lungiselela ubungakanani

• Ingongoma yoyilo 1: ukunciphisa i-transformer rhoqo kakhulu ubukhulu obuncinci

Kwibhodi yesekethe, ungabona ukuba ivolumu enkulu yitransformer, ngoko ke ukunciphisa ubungakanani betransformer kunokusindisa ubungakanani bebhodi. Ifrikhwensi ephezulu inokunciphisa ubungakanani betransformer kunye nokudluliselwa kwamandla etransformer, ngoko ke ifrikhwensi ukusuka kwi-200 KHZ ->300 KHZ ->500KHZ inokunciphisa ivolumu yetransformer.

• Ingongoma yesi-2 yoyilo: Imo yokusebenza ye-CCM inciphisa ubungakanani besixhobo

• Ingongoma yoyilo 3: Impendulo yokuqala ecaleni yokunciphisa ubungakanani

Ukwandisa ukusebenza kakuhle

I-EMC ilinganisa ukuphazamiseka okubangelwa yimithombo yengxolo kwizixhobo ezibuthathaka, kuquka ukuhanjiswa kwengxolo kunye nezinto ezibangela imitha. Kwelinye icala, imithombo yokuphazamiseka kufuneka incitshiswe kwaye iindlela zokudibanisa kufuneka zilungiswe kwelinye icala.

Ukuze kuncitshiswe i-EMI, umthombo wengxolo kwisekethe kufuneka uqinisekiswe kuqala. Umthombo wengxolo unokwahlulwa ube ngumthombo wengxolo yokuqhuba kunye nomthombo wengxolo yemitha. Umthombo wengxolo oqhutywayo ngokubanzi yingxolo yefrikhwensi ephantsi ngaphakathi kwe-30MHZ, eveliswa kukutshintsha kwentsimi yombane. Umthombo wengxolo oqhubayo ngokuyintloko kukuba isenzo sokutshintsha kwetyhubhu yamandla siya kukhokelela ekuguqulweni kwevolthi yomthombo we-MOS, eya kubangela ukuba i-transformer idlulisele utshintsho lwevolthi kwicala lesibini. Ukuphucula ukumelana nokuqhuba kwe-MOS kunokunciphisa isantya sokutshintsha, kodwa ilahleko yokuqhuba iya kwanda. Okanye yongeza iisekethe zokufunxa ukuze unciphise ukushukuma kwamaza aphezulu. Iiparamitha ezilahlekileyo ze-transformer zinempembelelo enkulu kwi-EMI, umzekelo, i-transformer Cp (intsimi yombane ejikelezayo ephambili) ichaphazela ii-voltage spikes kunye ne-current ripple.

Umthombo wengxolo ekhutshwayo yingxolo engaphezulu kwe-30M, oku kukuphazamiseka kwentsimi yemagnethi yesithuba. Yenziwe yiluphu yamandla ajikelezayo aphezulu. Iluphu yamandla aphezulu ibhekisa kwiluphu esecaleni ephambili kunye neluphu esecaleni yesibini yetransformer.