Rau lub sijhawm ntev, DC lub cev muaj zog tswj kev ceev tau tswj hwm cov ntawv thov uas xav tau kev tswj hwm kev kub ceev. Txawm li cas los xij, DC lub cev muaj zog muaj qhov tsis zoo, xws li hnav yooj yim ntawm cov txhuam hniav thiab cov commutators, yuav tsum tau saib xyuas ntau zaus. Commutation generates sparks, txwv lub cev muaj zog lub siab tshaj plaws ceev thiab txwv nws daim ntawv thov ib puag ncig. Tsis tas li ntawd, DC motors yog qhov nyuaj hauv cov qauv, nyuaj rau kev tsim khoom, siv cov hlau ntau, thiab muaj cov nqi tsim khoom siab. AC motors, tshwj xeeb tshaj yog squirrel-cage induction motors, tsis muaj cov teeb meem no, thiab lawv cov rotor inertia me dua li ntawm DC motors, ua rau cov lus teb zoo dua. Nyob rau hauv tib lub ntim, AC motors muaj peev xwm muaj 10% mus rau 70% siab zog tso zis ntau tshaj DC motors. Tsis tas li ntawd, AC motors tuaj yeem tsim nrog lub peev xwm loj dua, ua kom muaj zog dua thiab nrawm dua. Niaj hnub nimno CNC tshuab cuab yeej nyiam siv AC servo drives, uas yog nce hloov DC servo drives.
Hom Asynchronous
Asynchronous AC servo motors xa mus rau AC induction motors. Lawv muaj nyob rau hauv peb -theem thiab ib zaug-theem versions, thiab nyob rau hauv squirrel- tawb thiab qhov txhab-rotor hom, nrog squirrel- tawb peb-theem induction motors yog feem ntau. Nws cov qauv yog yooj yim, thiab piv rau DC lub cev muaj zog ntawm tib lub peev xwm, nws yog ib nrab ntawm qhov hnyav thiab tsuas yog ib qho - peb tus nqi. Qhov tsis zoo yog tias nws tsis tuaj yeem ua tiav kev tswj hwm kev ceev nrawm ntawm ntau qhov sib txawv, thiab yuav tsum tau kos cov kev tawm dag zog tam sim no los ntawm daim phiaj hluav taws xob. Qhov no ua rau lub zog ntawm cov kab hluav taws xob tsis zoo.
Hom squirrel no -cage rotor asynchronous AC servo motor tsuas yog hu ua asynchronous AC servo lub cev muaj zog, txhais los ntawm IM.
Hom Synchronous: Txawm hais tias synchronous AC servo motors yog ntau dua li induction motors, lawv yooj yim dua li DC motors. Nws lub stator yog tib yam li ntawm lub cev muaj zog induction, nrog peb qhov sib npaug ntawm -theem windings. Txawm li cas los xij, lub rotor txawv, thiab raws li cov qauv sib txawv, nws tau muab faib ua ob pawg: electromagnetic thiab tsis yog -electromagnetic. Tsis yog-electromagnetic synchronous motors tau muab faib ua hysteresis, cov hlau nplaum ruaj khov, thiab hom reactive. Hysteresis thiab reactive synchronous motors muaj qhov tsis zoo xws li kev ua haujlwm qis, lub zog tsis zoo, thiab muaj peev xwm tsim tau tsawg. Cov hlau nplaum ruaj khov synchronous motors feem ntau yog siv hauv CNC tshuab cuab yeej.
Piv rau cov tshuab hluav taws xob, cov hlau nplaum ruaj khov muaj qhov zoo ntawm cov qauv yooj yim, txhim khu kev lag luam, thiab kev ua haujlwm siab dua; qhov tsis zoo yog qhov loj thiab tsis zoo pib yam ntxwv. Txawm li cas los xij, los ntawm kev siv cov hlau nplaum tsis tshua muaj - lub ntiaj teb hlau nplaum nrog siab remanence thiab coercivity, cov hlau nplaum ruaj khov synchronous motors tuaj yeem kwv yees li ib nrab ntawm qhov loj thiab 60% sib zog dua DC motors, nrog rotor inertia txo mus rau ib - thib tsib ntawm DC motors. Piv rau asynchronous motors, lawv muaj txiaj ntsig zoo dua vim tias tshem tawm cov kev poob siab thiab cuam tshuam txog kev poob qis los ntawm cov hlau nplaum tas li excitation. Tsis tas li ntawd, vim tias lawv tsis muaj lub nplhaib plam thiab txhuam uas xav tau los ntawm electromagnetic synchronous motors, lawv cov kev ntseeg tau zoo ib yam li induction (asynchronous) motors, thaum lawv lub zog muaj zog ntau dua, ua rau me me rau cov hlau nplaum ruaj khov synchronous motors. Qhov no yog vim hais tias nyob rau hauv qis speeds, induction (asynchronous) motors, vim hais tias ntawm lawv cov tsis muaj hwj chim yam, muaj ib tug ntau npaum li cas pom lub zog rau tib lub zog ntawm lub active zog, thiab lub ntsiab qhov ntev ntawm lub cev muaj zog yog txiav txim los ntawm lub meej zog.