Abahlinzeki bemishini esekela i-frequency converter bakukhumbuza ukuthi ohlelweni lokulawula imvamisa yendabuko oluhlanganisa iziguquli zemvamisa yendawo yonke, amamotho asynchronous kanye nemithwalo yemishini, lapho umthwalo omncane wamandla oshayelwa injini ukhishwa, injini ingase ibe sesimweni sokubhuleka sokukhiqiza amandla kabusha; Noma lapho injini yehla isuka ejubaneni elikhulu iye ejubaneni eliphansi (okuhlanganisa nokuma), imvamisa ingase yehle, kodwa ngenxa ye-inertia yemishini yemoto, injini ingase ibe sesimweni sokukhiqiza amandla kabusha, futhi amandla omshini agciniwe ohlelweni lokudlulisela aguqulwa abe ugesi ngenjini kagesi, ebuyiselwa kusekethe we-DC we-inverter ngokusebenzisa i-ditero eqhubekayo eyisithupha yamanje.
Eziguqulini ezijwayelekile, kunezindlela ezimbili ezisetshenziswa kakhulu zokucubungula amandla avuselelekayo:
(1) "Ukumelana ne-Braking" ngokuhambisana ne-capacitor esethwe ngokuzenzakalelayo kusekethe ye-DC, ebizwa ngokuthi i-dynamic braking state;
(2), ibuyisele kugridi, ibizwa nge-feedback braking state (eyaziwa nangokuthi yi-regenerative braking state). Kukhona futhi indlela yokubhuleka, okungukuthi, i-DC braking, ingasetshenziswa ezimeni ezidinga ukupaka okunembile noma ukujikeleza okungavamile kwe-motor brake ngaphambi kokuqala ngenxa yezinto zangaphandle.
Ezincwadini nasezincwadini, ochwepheshe abaningi bakhulume ngokuklama nokusetshenziswa kwe-inverter braking, ikakhulukazi muva nje kube nezihloko eziningi mayelana "ne-energy feedback braking". Namuhla, umlobi unikeza uhlobo olusha lwe-braking method, enezinzuzo zokusebenza ezine-quadrant "i-feedback braking", ukusebenza kahle okuphezulu, futhi kunezinzuzo "zokusebenzisa amandla okusebenzisa amandla" kugridi ngaphandle kokungcola, ukwethembeka okuphezulu.
I-Energy Brake
Ukusebenzisa ukumelana namabhuleki okusethwe kusekethe ye-DC ukuze kuncelwe amandla kagesi avuselelekayo enjini kubizwa ngokuthi i-energy ukusetshenziswa braking.
Izinzuzo zayo ukwakhiwa okulula; Akukho ukungcola kugridi (uma kuqhathaniswa nempendulo), izindleko eziphansi; Okubi wukusebenza kahle okuphansi, ikakhulukazi uma ukubhuleka njalo kuzodla amandla amaningi futhi namandla okumelana namabhuleki azokhula.
Ngokuvamile, kusiguquli sefrikhwensi evamile, isiguquli samandla amancane (ngaphansi kuka-22kW) sineyunithi yebhuleki eyakhelwe ngaphakathi, idinga kuphela ukwengeza ukumelana namabhuleki. Isiguquli sefrikhwensi yamandla aphezulu (ngaphezulu kuka-22kW) sidinga iyunithi yamabhuleki yangaphandle, ukumelana namabhuleki.
Impendulo Brake
Ukuze uzuze ukubhuleka kwempendulo yamandla kudinga i-voltage nefrikhwensi kanye nokulawulwa kwesigaba, isilawuli samanje sempendulo nezinye izimo. Kuwukusetshenziswa kobuchwepheshe bokubuyisela emuva obusebenzayo, ukubuyisela ugesi ovuselelekayo kugridi ngefrikhwensi efanayo namandla wesigaba se-AC ubuyele kugridi, ngaleyo ndlela kuzuzwe ukubhuleka.
Inzuzo ye-feedback braking ukuthi ingasebenzisa ama-quadrants amane, njengoba kukhonjisiwe kuMfanekiso 3, impendulo yamandla kagesi ithuthukisa ukusebenza kahle kwesistimu. Ububi bayo yilezi:
(1), kuphela ngaphansi kwamandla kagesi wegridi azinzile okungelula ukwehluleka ukwehluleka (ukuguquguquka kwamandla kagesi wegridi akungaphezu kuka-10%), le ndlela yokubhuleka impendulo ingasetshenziswa. Ngoba uma ibhuleki lokukhiqiza amandla lisebenza, isikhathi sokuhluleka kwegridi kagesi sikhulu kuno-2ms, kungase kwenzeke ukwehluleka koshintsho lwesigaba, kulimaze idivayisi.
(2) Empendulweni, kukhona ukungcoliswa kwe-harmonic kugridi.
(3) Ukulawula okuyinkimbinkimbi, izindleko eziphezulu.
Uhlobo olusha lokubhuleka (i-capacitive feedback braking)
Isimiso sokujikeleza esiyinhloko
Ingxenye yokulungiswa isebenzisa ibhuloho elivamile lokulungiswa okungalawuleki ukuze kulungiswe, isifunda sokuhlunga sisebenzisa i-electrolytic capacitor evamile, isifunda sokulibaziseka sisebenzisa i-contactor noma i-silicon elawulekayo. Ukushaja, imojuli yamandla okuhambisa impendulo ye-IGBT, ukushaja, ukumelana nempendulo L kanye ne-electrolytic capacitor C enkulu (umthamo ungamaphoyinti ayiziro, unganqunywa ngokuya ngesistimu yokusebenza lapho isiguquli semvamisa sikhona). Ingxenye ye-inverter iqukethe imojula yamandla ye-IGBT. Isekhethi yokuvikela iqukethe i-IGBT, isivimbeli samandla.
(1) Isimo sokusebenza kokukhiqiza amandla kagesi
I-CPU yokuqapha ngesikhathi sangempela okokufaka kagesi we-AC kanye ne-DC circuit voltage νd, inquma ukuthi izothumela yini isignali yokushaja ku-VT1, uma i-νd isingaphezu kwe-voltage ye-AC yokufaka ehambisana nenani lamandla kagesi e-DC (isb. 380VAC-530VDC) enanini elithile, i-CPU ivala i-VT3, ngokusebenzisa i-pulse conduction ye-VTpaci ye-charging ngesikhathi senqubo ye-electrolyte. i-resistor L ihlukaniswe yaba yi-electrolytic capacitor C, ngaleyo ndlela iqinisekisa ukuthi i-electrolytic capacitor C isebenza ngaphakathi kwebanga eliphephile.
(2) Isimo sokusebenza kukagesi wemoto kagesi
Lapho i-CPU ithola ukuthi isistimu ayisakhokhiswa, iqhuba i-VT3 pulse, ukuze umugqa ku-resistor L ube i-voltage engalungile yesokunxele nesokudla (njengoba kukhonjisiwe kusithonjana), kanye ne-voltage ku-electrolytic capacitor C ingafinyelela inqubo yempendulo yamandla kusuka ku-capacitor kuya kusekethe ye-DC. I-CPU ilawula imvamisa yokushintsha ye-VT3 kanye nesilinganiso sezikhala ngokuthola amandla kagesi kanye nesekhethi ye-DC ku-electrolytic capacitor C, ngaleyo ndlela ilawula impendulo yamanje ukuze iqinisekise ukuthi i-DC circuit voltage νd ayibonakali iphezulu kakhulu.
Izinkinga zesistimu
(1) Ukukhethwa kwe-resistor
(a) Sibheka izici ezingavamile zezimo zokusebenza, sicabanga ukuthi uhlelo lunohlobo oluthile lokwehluleka, okuholela ekusheshiseni kwamahhala komthwalo webhithi equkethwe emotweni, lapho injini isesimweni sokusebenza kokukhiqiza amandla,
Amandla avuselelekayo abuyiselwa kumjikelezo we-DC ngokusebenzisa ama-diode amanje ayisithupha aqhubekayo, okubangela ukuthi i-νd iphakame, ngokushesha okwenza isiguquli semvamisa sibe esimweni sokushaja, ngaleso sikhathi okwamanje kuzoba kukhulu. Ngakho-ke i-diameter ye-resistor wire ekhethiwe kufanele ibe nkulu ngokwanele ukudlula okwamanje ngalesi sikhathi.
(b), ku-loop yempendulo, ukuze kwenziwe i-electrolytic capacitor ngaphambi kokukhokhiswa okulandelayo ukukhulula amandla kagesi amaningi ngangokunokwenzeka, ukukhetha kwensimbi evamile (i-silicon steel plate) ayikwazi ukufeza inhloso, kungcono ukhethe i-iron core eyenziwe ngezinto ze-ferrous oxide, bese ubheka ukucatshangelwa okungenhla kwenani lamanje kukhulu kakhulu, ungabona ukuthi le nsimbi enkulu kangakanani angazi ngisho noma kukhona umgogodla wensimbi ukuthi, inani layo ngokuqinisekile ngeke libe phansi kakhulu.
Ngakho-ke, ngiphakamisa ukuthi ukushaja kanye nesekhethi yempendulo ngayinye isebenzise i-resistor kagesi.
(2) Ubunzima bokulawula
(a) Kumjikelezo we-DC wesiguquli sefrikhwensi, i-voltage νd ngokuvamile ingaphezulu kuka-500VDC, futhi i-voltage yokumelana ye-electrolytic capacitor C ingu-400VDC kuphela. Kuyabonakala ukuthi ukulawulwa kwale nqubo yokushaja akufani nendlela yokulawula ye-energy braking (i-resistance braking). I-voltage yayo yesikhashana ku-resistor iyancipha ibe, i-voltage yokushaja yesikhashana ye-electrolytic capacitor C ingu-νc = νd-νL, ukuze kuqinisekiswe ukuthi i-electrolytic capacitor isebenza ngaphakathi kwebanga lokuphepha (≤400V), kuyadingeka ukulawula ngempumelelo ukwehla kwe-voltage νL ku-resistor, futhi ukwehla kwamandla kagesi νL kuncike enanini lamanje le-inductance.
(b) Enqubweni yempendulo, amandla kagesi akhishwe i-electrolytic capacitor C kumele futhi avinjwe ekubangeleni amandla kagesi wesekethe ye-DC ngokweqisa ngesixhasi, ukuze isistimu ibonakale ivikela ukugcwala kwamandla.
Izicelo Eziyinhloko Nezibonelo Zokusebenza
Kungenxa yezinzuzo zalolu hlobo olusha lwe-braking (i-capacitive feedback braking) ye-converter frequency, muva nje, abasebenzisi abaningi baye bahlongoza ukuhlomisa lesi simiso ngezici zemishini yabo. Ngenxa yobunzima bezobuchwepheshe, akwaziwa ukuthi ikhona yini indlela yokubhuleka phesheya. Njengamanje, yiShandong Fengguan Electronics Co., Ltd. kuphela eshintshele kulolu hlobo olusha lwekheshi yezimayini yochungechunge lwe-capacitive feedback braking kusukela kusiguquli sefrikhwensi esasebenzisa i-feed braking esikhathini esidlule (kusekuse-2 ekusebenzeni okujwayelekile), kuze kube manje, le-capacitive feedback braking frequency converter ibisebenza ngokujwayelekile isikhathi eside eMayini ye-Tandong Ningan, e-Shandong Home Security kanye ne-Shangyang Security Gcwalisa
Ngokunwetshwa kwenkambu yezinhlelo zokusebenza ze-frequency converter, lobu buchwepheshe bohlelo lokusebenza buzothembisa kakhulu, ikakhulukazi, ikakhulukazi, busetshenziswa ekhejini elilenga emayini (elinomuntu noma elilayishwayo), iloli yezimayini ye-bevel well (isilinda esisodwa noma esiphindwe kabili), imishini yokuphakamisa kanye nezinye izimboni. Ngamafuphi, isidingo samadivayisi wempendulo yamandla singasetshenziswa.