一、伺服電機的工作原理
伺服電機是常用電機的一種,它是一種絕對服從控制信號指揮的電機,設計用于精確定位而不是可控速。伺服電機一般由定子和轉子構成,定子上有兩個繞組,即勵磁繞組和控制繞組,兩個繞組在空間相差90°電角度,內部的電流、角度、偏心度等信號,通過一根電纜連接于伺服器,伺服器以此來修正對伺服電機的驅動信號。由于服電機本身具備發出脈沖的功能,伺服主要靠脈沖來定位,伺服電機每旋轉一個角度,都會發出對應數量的脈沖,這樣,和伺服電機接受的脈沖形成了呼應,或者叫閉環,如此一來,系統就會知道發了多少脈沖給伺服電機,同時又收了多少脈沖回來,這樣,就能夠很精確的控制電機的轉動,從而實現精確的定位,可以達到0.001mm。如果您需要購買伺服電機,可以先來了解一下伺服電機十大品牌。
二、伺服電機驅動器的作用和功能
伺(si)服(fu)(fu)電(dian)(dian)機(ji)驅(qu)動(dong)(dong)器,簡稱伺(si)服(fu)(fu)驅(qu)動(dong)(dong)器,屬于伺(si)服(fu)(fu)系統的(de)一(yi)部分,主(zhu)要應用于高精度的(de)定位系統,是用來控(kong)制伺(si)服(fu)(fu)電(dian)(dian)機(ji)的(de)一(yi)種控(kong)制器,它的(de)功能(neng)(neng)細分的(de)話有很多(duo)種,包括:1、參(can)(can)數分組化設(she)置、控(kong)制模式再(zai)線任意切換。2、控(kong)制電(dian)(dian)源交流(liu)輸入(ru)、可設(she)置的(de)寬電(dian)(dian)壓輸入(ru)。3、瞬間掉電(dian)(dian)快速(su)停機(ji)保護(hu)功能(neng)(neng)。4、再(zai)生制動(dong)(dong)、動(dong)(dong)態(tai)制動(dong)(dong)功能(neng)(neng)。5、絕對值系統電(dian)(dian)壓監(jian)控(kong),低壓警(jing)告功能(neng)(neng)。6、調試(shi)軟件(jian)支持參(can)(can)數管理、監(jian)控(kong)、示(shi)波器功能(neng)(neng)。
三、伺服電機控制方式的三種基本形式
伺服電(dian)(dian)(dian)機(ji)的(de)(de)(de)(de)(de)(de)(de)(de)控(kong)(kong)制(zhi)(zhi)(zhi)方(fang)(fang)式主要有(you)三種,分(fen)別是(shi)轉(zhuan)(zhuan)矩(ju)控(kong)(kong)制(zhi)(zhi)(zhi)、位(wei)(wei)(wei)置(zhi)(zhi)控(kong)(kong)制(zhi)(zhi)(zhi)和速(su)度(du)(du)模(mo)式:1、轉(zhuan)(zhuan)矩(ju)控(kong)(kong)制(zhi)(zhi)(zhi):轉(zhuan)(zhuan)矩(ju)控(kong)(kong)制(zhi)(zhi)(zhi)方(fang)(fang)式是(shi)通(tong)(tong)過外(wai)(wai)部模(mo)擬(ni)量的(de)(de)(de)(de)(de)(de)(de)(de)輸入(ru)或直(zhi)接(jie)的(de)(de)(de)(de)(de)(de)(de)(de)地址的(de)(de)(de)(de)(de)(de)(de)(de)賦值(zhi)來(lai)(lai)設定(ding)電(dian)(dian)(dian)機(ji)軸對外(wai)(wai)的(de)(de)(de)(de)(de)(de)(de)(de)輸出轉(zhuan)(zhuan)矩(ju)的(de)(de)(de)(de)(de)(de)(de)(de)大(da)小,可(ke)(ke)以(yi)通(tong)(tong)過即(ji)時(shi)的(de)(de)(de)(de)(de)(de)(de)(de)改(gai)(gai)變(bian)模(mo)擬(ni)量的(de)(de)(de)(de)(de)(de)(de)(de)設定(ding)來(lai)(lai)改(gai)(gai)變(bian)設定(ding)的(de)(de)(de)(de)(de)(de)(de)(de)力矩(ju)大(da)小,也可(ke)(ke)通(tong)(tong)過通(tong)(tong)訊(xun)方(fang)(fang)式改(gai)(gai)變(bian)對應的(de)(de)(de)(de)(de)(de)(de)(de)地址的(de)(de)(de)(de)(de)(de)(de)(de)數(shu)值(zhi)來(lai)(lai)實(shi)現。2、位(wei)(wei)(wei)置(zhi)(zhi)控(kong)(kong)制(zhi)(zhi)(zhi) 位(wei)(wei)(wei)置(zhi)(zhi)控(kong)(kong)制(zhi)(zhi)(zhi)模(mo)式一般是(shi)通(tong)(tong)過外(wai)(wai)部輸入(ru)的(de)(de)(de)(de)(de)(de)(de)(de)脈(mo)沖(chong)的(de)(de)(de)(de)(de)(de)(de)(de)頻(pin)率來(lai)(lai)確定(ding)轉(zhuan)(zhuan)動(dong)(dong)速(su)度(du)(du)的(de)(de)(de)(de)(de)(de)(de)(de)大(da)小,通(tong)(tong)過脈(mo)沖(chong)的(de)(de)(de)(de)(de)(de)(de)(de)個數(shu)來(lai)(lai)確定(ding)轉(zhuan)(zhuan)動(dong)(dong)的(de)(de)(de)(de)(de)(de)(de)(de)角度(du)(du),也有(you)些(xie)伺服可(ke)(ke)以(yi)通(tong)(tong)過通(tong)(tong)訊(xun)方(fang)(fang)式直(zhi)接(jie)對速(su)度(du)(du)和位(wei)(wei)(wei)移進行賦值(zhi)。3、速(su)度(du)(du)模(mo)式:通(tong)(tong)過模(mo)擬(ni)量的(de)(de)(de)(de)(de)(de)(de)(de)輸入(ru)或脈(mo)沖(chong)的(de)(de)(de)(de)(de)(de)(de)(de)頻(pin)率都可(ke)(ke)以(yi)進行轉(zhuan)(zhuan)動(dong)(dong)速(su)度(du)(du)的(de)(de)(de)(de)(de)(de)(de)(de)控(kong)(kong)制(zhi)(zhi)(zhi),在有(you)上位(wei)(wei)(wei)控(kong)(kong)制(zhi)(zhi)(zhi)裝(zhuang)置(zhi)(zhi)的(de)(de)(de)(de)(de)(de)(de)(de)外(wai)(wai)環(huan)PID控(kong)(kong)制(zhi)(zhi)(zhi)時(shi)速(su)度(du)(du)模(mo)式也可(ke)(ke)以(yi)進行定(ding)位(wei)(wei)(wei),但必須把電(dian)(dian)(dian)機(ji)的(de)(de)(de)(de)(de)(de)(de)(de)位(wei)(wei)(wei)置(zhi)(zhi)信(xin)號或直(zhi)接(jie)負(fu)載(zai)的(de)(de)(de)(de)(de)(de)(de)(de)位(wei)(wei)(wei)置(zhi)(zhi)信(xin)號給上位(wei)(wei)(wei)反饋以(yi)做運算用(yong)。
四、伺服電機和步進電機的區別
步(bu)(bu)進(jin)(jin)電(dian)(dian)(dian)(dian)機(ji)(ji)(ji)和伺服電(dian)(dian)(dian)(dian)機(ji)(ji)(ji)都是電(dian)(dian)(dian)(dian)機(ji)(ji)(ji),兩種電(dian)(dian)(dian)(dian)機(ji)(ji)(ji)比較起(qi)來有一(yi)(yi)定(ding)(ding)的(de)(de)(de)(de)(de)區(qu)別(bie):1、控(kong)(kong)制(zhi)精(jing)度(du)(du)不同(tong):伺服電(dian)(dian)(dian)(dian)機(ji)(ji)(ji)的(de)(de)(de)(de)(de)控(kong)(kong)制(zhi)精(jing)度(du)(du)由電(dian)(dian)(dian)(dian)機(ji)(ji)(ji)軸(zhou)后端(duan)的(de)(de)(de)(de)(de)旋(xuan)轉(zhuan)(zhuan)編(bian)碼(ma)器保證,是步(bu)(bu)距(ju)角為(wei)1.8°的(de)(de)(de)(de)(de)步(bu)(bu)進(jin)(jin)電(dian)(dian)(dian)(dian)機(ji)(ji)(ji)的(de)(de)(de)(de)(de)脈(mo)沖當(dang)量的(de)(de)(de)(de)(de)1/655。2、低(di)(di)頻(pin)特(te)性(xing)不同(tong):步(bu)(bu)進(jin)(jin)電(dian)(dian)(dian)(dian)機(ji)(ji)(ji)在低(di)(di)速(su)(su)時(shi)(shi)(shi)易出(chu)現(xian)(xian)低(di)(di)頻(pin)振(zhen)動(dong)現(xian)(xian)象(xiang),振(zhen)動(dong)頻(pin)率(lv)與負(fu)載情況(kuang)和驅動(dong)器性(xing)能有關(guan);伺服電(dian)(dian)(dian)(dian)機(ji)(ji)(ji)運轉(zhuan)(zhuan)非常平穩(wen),即使在低(di)(di)速(su)(su)時(shi)(shi)(shi)也不會出(chu)現(xian)(xian)振(zhen)動(dong)現(xian)(xian)象(xiang)。3、矩(ju)(ju)頻(pin)特(te)性(xing)不同(tong):步(bu)(bu)進(jin)(jin)電(dian)(dian)(dian)(dian)機(ji)(ji)(ji)的(de)(de)(de)(de)(de)輸(shu)(shu)出(chu)力(li)(li)矩(ju)(ju)隨(sui)轉(zhuan)(zhuan)速(su)(su)升高(gao)而(er)下降,且在較高(gao)轉(zhuan)(zhuan)速(su)(su)時(shi)(shi)(shi)會急劇下降;伺服電(dian)(dian)(dian)(dian)機(ji)(ji)(ji)為(wei)恒力(li)(li)矩(ju)(ju)輸(shu)(shu)出(chu),在額定(ding)(ding)轉(zhuan)(zhuan)速(su)(su)內都能輸(shu)(shu)出(chu)額定(ding)(ding)轉(zhuan)(zhuan)矩(ju)(ju)。4、過載能力(li)(li)不同(tong):步(bu)(bu)進(jin)(jin)電(dian)(dian)(dian)(dian)機(ji)(ji)(ji)一(yi)(yi)般(ban)不具(ju)有過載能力(li)(li),伺服電(dian)(dian)(dian)(dian)機(ji)(ji)(ji)具(ju)有較強的(de)(de)(de)(de)(de)過載能力(li)(li),具(ju)有速(su)(su)度(du)(du)過載和轉(zhuan)(zhuan)矩(ju)(ju)過載功能。5、運行性(xing)能不同(tong):步(bu)(bu)進(jin)(jin)電(dian)(dian)(dian)(dian)機(ji)(ji)(ji)的(de)(de)(de)(de)(de)控(kong)(kong)制(zhi)為(wei)開(kai)環控(kong)(kong)制(zhi),啟動(dong)頻(pin)率(lv)過高(gao)或(huo)負(fu)載過大易出(chu)現(xian)(xian)丟(diu)步(bu)(bu)或(huo)堵轉(zhuan)(zhuan)的(de)(de)(de)(de)(de)現(xian)(xian)象(xiang),停(ting)止時(shi)(shi)(shi)轉(zhuan)(zhuan)速(su)(su)過高(gao)易出(chu)現(xian)(xian)過沖的(de)(de)(de)(de)(de)現(xian)(xian)象(xiang);伺服驅動(dong)系統為(wei)閉(bi)環控(kong)(kong)制(zhi),一(yi)(yi)般(ban)不會出(chu)現(xian)(xian)步(bu)(bu)進(jin)(jin)電(dian)(dian)(dian)(dian)機(ji)(ji)(ji)的(de)(de)(de)(de)(de)丟(diu)步(bu)(bu)或(huo)過沖的(de)(de)(de)(de)(de)現(xian)(xian)象(xiang),控(kong)(kong)制(zhi)性(xing)能更為(wei)可(ke)靠。6、速(su)(su)度(du)(du)響應(ying)性(xing)能不同(tong) 步(bu)(bu)進(jin)(jin)電(dian)(dian)(dian)(dian)機(ji)(ji)(ji)從靜(jing)止加(jia)(jia)速(su)(su)到工作轉(zhuan)(zhuan)速(su)(su)(一(yi)(yi)般(ban)為(wei)每分(fen)鐘幾百轉(zhuan)(zhuan))需要200~400毫秒;伺服電(dian)(dian)(dian)(dian)機(ji)(ji)(ji)系統的(de)(de)(de)(de)(de)加(jia)(jia)速(su)(su)性(xing)能較好,從靜(jing)止加(jia)(jia)速(su)(su)到其額定(ding)(ding)轉(zhuan)(zhuan)速(su)(su)3000RPM僅需幾毫秒。