Abahlinzeki bemishini yokonga i-elevator bakukhumbuza ukuthi iziguquli zefrikhwensi manje sezisetshenziswa kabanzi ezimbonini ezahlukahlukene, ezifana ne-air conditioning, amakheshi, nezimboni ezisindayo. Ngezansi, sizochaza ulwazi oluyisisekelo lokusebenzisa iziguquli zemvamisa kumakheshi:
1. Iyini i-frequency converter?
I-frequency converter iyithuluzi lokulawula amandla kagesi elisebenzisa umsebenzi wokucisha wamadivayisi we-semiconductor yamandla ukuguqula imithombo yefrikhwensi yamandla ibe enye ifrikhwensi.
2. Yimuphi umehluko phakathi kwe-PWM ne-PAM?
I-PWM isifinyezo se-Pulse Width Modulation ngesiNgisi, okuyindlela yokulungisa okukhiphayo kanye ne-waveform ngokushintsha ububanzi be-pulse yesitimela esishayelayo ngokuya ngephethini ethile. I-PAM imele i-Pulse Amplitude Modulation ngesiNgisi, okuyindlela yokushintshashintsha elungisa inani lokuphumayo kanye ne-waveform ngokushintsha i-pulse amplitude yesitimela esishayelayo ngokomthetho othile.
3. Uyini umehluko phakathi kohlobo lwe-voltage kanye nohlobo lwamanje?
Isifunda esiyinhloko se-converter ye-frequency singahlukaniswa cishe ngezigaba ezimbili: uhlobo lwe-voltage luyi-converter ye-frequency eguqula i-DC yomthombo we-voltage ibe yi-AC, futhi ukuhlunga kwesifunda se-DC kuyi-capacitor; Uhlobo lwamanje luyi-converter yefrikhwensi eguqula amandla akhona aqondile omthombo wamanje abe wamanje oshintshanayo, ngesihlungi sesekethe ye-DC kanye ne-inductor.
4. Kungani i-voltage ne-current yesiguquli se-frequency ishintsha ngokulinganayo?
I-torque ye-asynchronous motor ikhiqizwa ukuxhumana phakathi kwe-flux kazibuthe ye-motor kanye ne-current egeleza ku-rotor. Ku-frequency elinganiselwe, uma i-voltage ingaguquki futhi imvamisa kuphela iyancipha, i-flux kazibuthe izoba nkulu kakhulu, isifunda kazibuthe sizogcwala, futhi ezimeni ezinzima, injini izoshiswa. Ngakho-ke, i-frequency kanye ne-voltage kufanele kushintshwe ngokulinganayo, okungukuthi, ngenkathi kuguqulwa imvamisa, i-voltage ephumayo yesiguquli se-frequency kufanele ilawulwe ukuze kugcinwe ukugeleza kozibuthe okuthile kwenjini futhi kugwenywe ukwenzeka kozibuthe obuthaka kanye nezimo zikamagnetic saturation. Le ndlela yokulawula ijwayele ukusetshenziselwa iziguquli zefrikhwensi zokonga amandla kumafeni namaphampu.
5. Uma i-motor kagesi iqhutshwa umthombo wefrikhwensi yamandla, ukwanda kwamanje lapho i-voltage yehla; Nge-frequency converter drive, uma i-voltage nayo yehla lapho imvamisa yehla, ingabe ukwanda kwamanje?
Lapho imvamisa iyancipha (ngejubane eliphansi), uma amandla afanayo ephuma, ukwanda kwamanje, kodwa ngaphansi kwesimo se-torque eqhubekayo, okwamanje ihlala cishe ingashintshi.
6. Iyini i-torque yokuqala kanye ne-torque yokuqala ye-motor lapho usebenzisa isiguquli semvamisa ukusebenza?
Kusetshenziswa isiguquli sefrikhwensi ukuze sisebenze, imvamisa ne-voltage ziyanda ngokuhambisana nokusheshisa kwenjini, kanti isiqalo samanje sinqunyelwe ngaphansi kuka-150% wamanje olinganisiwe (125% ~ 200% kuye ngemodeli). Uma uqala ngokuqondile ngokunikezwa kwamandla kagesi, ukuqala kwamanje kuyizikhathi ezingu-6-7, okuholela ekushaqekeni kwemishini nogesi. Ukusebenzisa idrayivu yokuguqula imvamisa kungaqala kahle (ngesikhathi sokuqalisa eside). Ukuqala kwamanje izikhathi ezingu-1.2 ~ 1.5 zamanje ezilinganiselwe, futhi i-torque yokuqala i-70% ~ 120% ye-torque elinganiselwe; Kuziguquli zefrikhwensi ezinomsebenzi wokuthuthukisa ithoshi othomathikhi, itorque yokuqala ingaphezulu kuka-100% futhi ingaqala ngomthwalo ogcwele.
7. Isho ukuthini imodi ye-V/f?
Lapho imvamisa iyancipha, i-voltage V nayo iyancipha ngokulinganayo, njengoba kuchazwe empendulweni 4. Ubudlelwano obulinganayo phakathi kwe-V no-f bunqunywa kusengaphambili kucatshangelwa izici zemoto, futhi ngokuvamile kunezici eziningana ezigcinwe kudivayisi yokugcina (i-ROM) yesilawuli, engakhethwa kusetshenziswa ukushintshwa noma ukudayela.
8. Ishintsha kanjani i-torque ye-motor lapho u-V no-f eshintshwa ngokulinganayo?
Lapho imvamisa yehla futhi i-voltage yehla ngokulinganayo, ukwehla kwe-AC impedance ngenkathi ukumelana kwe-DC kuhlala kungashintshile kuzophumela ekuthambekeni kokunciphisa i-torque yaphansi ekhiqizwa ngesivinini esiphansi. Ngakho-ke, uma kunikezwe i-V/f kumafrikhwensi aphansi, kuyadingeka ukukhulisa i-voltage yokuphuma kancane ukuze uthole i-torque ethile yokuqala. Lesi sinxephezelo sibizwa ngokuthi ukuqala okuthuthukisiwe. Izindlela ezihlukahlukene zingasetshenziswa ukufeza lokhu, kuhlanganise nokusebenza okuzenzakalelayo, ukukhetha imodi ye-V/f, noma ukulungisa i-potentiometer.
9. Ingabe awekho amandla okukhiphayo angaphansi kuka-6Hz, njengoba imanuwali isho ububanzi besivinini obungu-60~6Hz, obungu-10:1?
Amandla asengaphuma ngaphansi kuka-6Hz, kodwa ngokusekelwe ekukhuphukeni kwezinga lokushisa kanye ne-torque yokuqala ye-motor, ubuncane befrikhwensi yokusebenza buzungeze u-6Hz. Ngalesi sikhathi, injini ingakhipha i-torque elinganiselwe ngaphandle kokubangela izinkinga ezinkulu zokushisa. Imvamisa yangempela yokuphumayo (imvamisa yokuqala) yesiguquli sefrikhwensi iyahlukahluka ukusuka ku-0.5 kuye ku-3Hz kuye ngemodeli.
10. Kungenzeka yini ukudinga i-torque engaguquki yezinhlanganisela zezimoto ezijwayelekile ezingaphezu kuka-60Hz?
Ngokuvamile akunakwenzeka. Lapho i-voltage ihlala ingashintshile ngaphezu kuka-60Hz (futhi kukhona namamodi angaphezu kuka-50Hz), ngokuvamile kuwuphawu lwamandla olungaguquki. Lapho i-torque efanayo idingeka ngesivinini esikhulu, ukunakwa kufanele kukhokhwe ekukhetheni umthamo we-motor kanye ne-inverter.
11. Kusho ukuthini i-open-loop '?
I-speed detector (PG) ifakwe emshinini osetshenziselwa ukubuyisela isivinini sangempela kudivayisi yokulawula ukuze uyilawule, ebizwa ngokuthi "iluphu evaliwe". Uma ingasebenzi nge-PG, ibizwa ngokuthi "i-loop evulekile". Iziguquli zefrikhwensi ezivamile ngokuvamile ziyi-loop evulekile, futhi amanye amamodeli angasebenzisa izinketho zempendulo ye-PG.
12. Yini okufanele yenziwe lapho ijubane langempela liphambuka esivinini esinikeziwe?
Uma i-open-loop, ngisho noma isiguquli sefrikhwensi sikhipha imvamisa enikeziwe, isivinini semoto siyahlukahluka phakathi kwebanga lokushelela elilinganiselwe (1%~5%) uma lisebenza nomthwalo. Ezimweni lapho kudingeka ukunemba kokulawula isivinini esikhulu futhi ngisho nezinguquko zomthwalo zidinga ukusebenza eduze nesivinini esinikeziwe, isiguquli semvamisa esinomsebenzi wempendulo ye-PG (kuyakhetheka) singasetshenziswa.
13. Uma injini ene-PG isetshenziselwa impendulo, ingabe ukunemba kwesivinini kungathuthukiswa?
Isiguquli semvamisa esinomsebenzi wempendulo ye-PG sithuthukise ukunemba. Kodwa ukunemba kwejubane kuncike ekunembeni kwe-PG ngokwayo kanye nesinqumo semvamisa yokuphuma kwesiguquli semvamisa.
14. Kusho ukuthini umsebenzi wokuvimbela itafula?
Uma isikhathi esinikeziwe sokusheshisa sisifushane kakhulu futhi imvamisa yokuphuma kwesiguquli semvamisa ishintsha kakhulu kunejubane (imvamisa ye-angular kagesi), isiguquli sefrikhwensi sizokhubeka futhi siyeke ukusebenza ngenxa ye-overcurrent, ebizwa ngokuthi i-stall. Ukuze uvimbele injini ukuthi ingaqhubeki nokusebenza ngenxa ye-stall, kuyadingeka ukuthola ubukhulu bamanje bokulawula imvamisa. Uma i-acceleration yamanje iphezulu kakhulu, yehlisa izinga lokusheshisa ngokufanele. Okufanayo kusebenza lapho wehlisa ijubane. Inhlanganisela yakho kokubili umsebenzi wokudayisa.
15. Kuyini ukubaluleka kwamamodeli anesikhathi sokusheshisa esinikezwe ngokwehlukana nesikhathi sokwehla, namamodeli anesikhathi sokusheshisa esinikezwe ngokuhlanganyela kanye nesikhathi sokwehlisa?
Ukusheshisa nokunciphisa kunganikezwa ngokuhlukana kwezinhlobo ezahlukene zemishini, efanelekile ukusheshisa kwesikhashana, izimo zokunciphisa kancane, noma izimo lapho isikhathi somjikelezo wokukhiqiza esiqinile sidingeka kumathuluzi emishini emincane. Kodwa-ke, ezimweni ezinjengokudluliswa kwabalandeli, izikhathi zokusheshisa nezokuncishiswa zinde kakhulu, futhi kokubili izikhathi zokusheshisa nokunciphisa zinganikezwa ndawonye.
16. Kuyini i-regenerative braking?
Uma i-frequency yomyalo iyancipha ngesikhathi sokusebenza kwe-motor kagesi, izoba i-generator e-asynchronous futhi isebenze njenge-brake, ebizwa ngokuthi i-regenerative (electrical) braking.
17. Iyini impendulo yamandla ekheshi?
Guqula amandla e-DC akhona futhi angenamsebenzi wekheshi abe amandla e-AC asebenzisekayo nasebenzayo. Inqubo yokubuyisela ngesikhathi esisodwa amandla e-AC ahlanekezelwe kunethiwekhi yendawo eduze nekheshi ukuze aphinde asetshenziswe.