Umahluko ophambili phakathi kwemoto eqhutywa ngamandla okuguqulwa kwamaza kunye nemoto eqhutywa ngamandla amaza e-sine frequency kukuba kwelinye icala, isebenza kuluhlu olubanzi lwamaza ukusuka kwi-frequency ephantsi ukuya kwi-frequency ephezulu, kwaye kwelinye icala, i-power waveform ayisebenzi kwi-sinusoidal. Ngokusebenzisa uhlalutyo lwe-Fourier series lwe-voltage waveform, i-power supply waveform iqulethe ii-harmonics ezingaphezu kwe-2N ukongeza kwi-fundamental wave component (control wave) (inani lamaza e-modulation aqulethwe kwisiqingatha ngasinye se-control wave yi-N). Xa i-SPWM AC converter ikhupha amandla kwaye iwasebenzise kwi-motor, i-current waveform kwi-motor iya kuvela njenge-sine wave ene-superimposed harmonics. I-harmonic current iya kuvelisa i-pulsating magnetic flux component kwi-magnetic circuit ye-asynchronous motor, kwaye i-pulsating magnetic flux component ibekwe kwi-main magnetic flux, ukuze i-main magnetic flux ibe ne-pulsating magnetic flux component. I-pulsating magnetic flux component ikwenza i-magnetic circuit ithambekele ekubeni igcwale, eneziphumo ezilandelayo ekusebenzeni kwe-motor:
1. Ukujikeleza kwemagnethi okutyhafayo kuyaveliswa
Ilahleko iyanda kwaye ukusebenza kakuhle kuyancipha. Ngenxa yokuba imveliso yombane oguquguqukayo iqulethe inani elikhulu leeharmonics eziphezulu, ezi harmonics ziya kuvelisa ukusetyenziswa kobhedu kunye nesinyithi okuhambelanayo, kunciphisa ukusebenza kakuhle. Kwanobuchwepheshe be-SPWM sinusoidal pulse width, obusetyenziswa kakhulu okwangoku, buthintela kuphela iiharmonics eziphantsi kwaye bunciphise i-torque ye-pulsating yemoto, ngaloo ndlela bandisa uluhlu oluzinzileyo lokusebenza kwemoto ngesantya esiphantsi. Kwaye iiharmonics eziphezulu azizange zehle nje kuphela, kodwa zanda. Ngokubanzi, xa kuthelekiswa nombane we-frequency sine, ukusebenza kakuhle kuncitshiswa nge-1% ukuya kwi-3%, kwaye i-power factor incitshiswa nge-4% ukuya kwi-10%, ngoko ke ukulahleka kwe-harmonic kwemoto phantsi kombane wokuguqulwa kwamaza yingxaki enkulu.
b) Ukuvelisa ukungcangcazela kunye nengxolo ye-electromagnetic. Ngenxa yokuba kukho uthotho lwee-harmonics eziphezulu, ukungcangcazela kunye nengxolo ye-electromagnetic kuya kuveliswa. Indlela yokunciphisa ukungcangcazela kunye nengxolo sele iyingxaki kwiimoto ezisebenzisa i-sine wave. Kwimoto eqhutywa yi-inverter, ingxaki iba nzima ngakumbi ngenxa yendalo yombane ongekho sinusoidal.
c) I-torque ebetha ngamandla aphantsi yenzeka ngesantya esiphantsi. Amandla e-harmonic magnetomotive kunye ne-rotor harmonic current synthesis, ekhokelela kwi-torque ebetha ngamandla angapheliyo kunye ne-torque ebetha ngamandla ahlukeneyo, i-torque ebetha ngamandla ahlukeneyo iya kwenza i-motor pulsation, ngaloo ndlela ichaphazela ukusebenza okuzinzileyo ngesantya esiphantsi. Nokuba kusetyenziswa i-modulation mode ye-SPWM, xa kuthelekiswa nombane we-power frequency sine, kuya kubakho inqanaba elithile le-harmonics ephantsi, eya kuvelisa i-torque ebetha ngamandla ngesantya esiphantsi kwaye ichaphazele ukusebenza okuzinzileyo kwe-motor ngesantya esiphantsi.
2. Yenza i-voltage ye-impulse kunye ne-axial voltage (yangoku) kwi-insulation
a) Kwenzeka i-voltage yokunyukela. Xa injini isebenza, i-voltage esetyenzisiweyo idla ngokuxhonywa yi-voltage yokunyukela eyenziweyo xa izinto ezikwisixhobo sokuguqula amaza zitshintshiwe, kwaye ngamanye amaxesha i-voltage yokunyukela iphezulu, nto leyo ebangela ukubetheka kombane okuphindaphindiweyo kwi-coil kunye nomonakalo kwi-insulation.
b) Ukuvelisa i-axial voltage kunye ne-axial current. Ukuveliswa kwe-shaft voltage kubangelwa kakhulu kukubakho kokungalingani kwesekethe yemagnethi kunye ne-electrostatic induction phenomenon, engeyonto imbi kwiimoto eziqhelekileyo, kodwa ibonakala ngakumbi kwiimoto ezisebenza ngamandla ombane aguquguqukayo. Ukuba i-shaft voltage iphezulu kakhulu, imeko yokuthambisa yefilimu yeoyile phakathi kwe-shaft kunye ne-bearing iya konakala, kwaye ubomi benkonzo ye-bearing buya kufutshane.
c) Ukusasazwa kobushushu kuchaphazela isiphumo sokusasazwa kobushushu xa kuqhutywa ngesantya esiphantsi. Ngenxa yoluhlu olukhulu lolawulo lwesantya semoto eguquguqukayo, ihlala isebenza ngesantya esiphantsi kwisantya esiphantsi. Ngeli xesha, ngenxa yokuba isantya siphantsi kakhulu, umoya opholileyo obonelelwa yindlela yokupholisa ifeni esetyenziswa yimoto eqhelekileyo awanelanga, kwaye isiphumo sokusasazwa kobushushu sinciphile, kwaye kufuneka kusetyenziswe ukupholisa ifeni ezimeleyo.
Impembelelo yoomatshini ithambekele ekuvuseleleni, ngokubanzi, nasiphi na isixhobo soomatshini siya kuvelisa i-resonance phenomenon. Nangona kunjalo, i-motor esebenza nge-frequency yamandla angaguqukiyo kunye nesantya kufuneka iphephe i-resonance nge-frequency yendalo yomatshini yempendulo ye-frequency yombane ye-50Hz. Xa i-motor isebenza ngokuguqulwa kwe-frequency, i-frequency yokusebenza inoluhlu olubanzi, kwaye icandelo ngalinye line-frequency yalo yendalo, elula ukuyenza ijikeleze kwi-frequency ethile.
Ixesha leposi: Februwari-25-2025