一、什么是隨動系統
隨動系統servo system，是(shi)一(yi)(yi)(yi)種(zhong)(zhong)反(fan)饋控(kong)(kong)制系(xi)(xi)(xi)(xi)統(tong)(tong)(tong)(tong)(tong)。在(zai)(zai)這種(zhong)(zhong)系(xi)(xi)(xi)(xi)統(tong)(tong)(tong)(tong)(tong)中，輸(shu)(shu)(shu)(shu)出(chu)量(liang)(liang)(liang)是(shi)機械位(wei)移、速(su)度或者加速(su)度。因此隨(sui)(sui)動(dong)系(xi)(xi)(xi)(xi)統(tong)(tong)(tong)(tong)(tong)這一(yi)(yi)(yi)術語，與位(wei)置或速(su)度，或加速(su)度控(kong)(kong)制系(xi)(xi)(xi)(xi)統(tong)(tong)(tong)(tong)(tong)是(shi)同義語。在(zai)(zai)隨(sui)(sui)動(dong)系(xi)(xi)(xi)(xi)統(tong)(tong)(tong)(tong)(tong)中，有一(yi)(yi)(yi)類(lei)，它(ta)的(de)(de)參(can)考輸(shu)(shu)(shu)(shu)入(ru)(ru)不是(shi)時間(jian)的(de)(de)解析(xi)函(han)數(shu)，如何變(bian)(bian)化(hua)(hua)(hua)(hua)事先并(bing)不知(zhi)(zhi)道(dao)（隨(sui)(sui)著時間(jian)任意(yi)變(bian)(bian)化(hua)(hua)(hua)(hua)）。控(kong)(kong)制系(xi)(xi)(xi)(xi)統(tong)(tong)(tong)(tong)(tong)的(de)(de)任務是(shi)在(zai)(zai)各種(zhong)(zhong)情況下保(bao)證輸(shu)(shu)(shu)(shu)出(chu)以一(yi)(yi)(yi)定(ding)精度跟(gen)隨(sui)(sui)著參(can)考輸(shu)(shu)(shu)(shu)入(ru)(ru)的(de)(de)變(bian)(bian)化(hua)(hua)(hua)(hua)而(er)變(bian)(bian)化(hua)(hua)(hua)(hua)。微機位(wei)置伺服系(xi)(xi)(xi)(xi)統(tong)(tong)(tong)(tong)(tong)概述在(zai)(zai)自(zi)動(dong)控(kong)(kong)制系(xi)(xi)(xi)(xi)統(tong)(tong)(tong)(tong)(tong)中，把輸(shu)(shu)(shu)(shu)出(chu)量(liang)(liang)(liang)能夠以一(yi)(yi)(yi)定(ding)準確(que)度跟(gen)隨(sui)(sui)輸(shu)(shu)(shu)(shu)入(ru)(ru)量(liang)(liang)(liang)的(de)(de)變(bian)(bian)化(hua)(hua)(hua)(hua)而(er)變(bian)(bian)化(hua)(hua)(hua)(hua)的(de)(de)系(xi)(xi)(xi)(xi)統(tong)(tong)(tong)(tong)(tong)稱(cheng)(cheng)為隨(sui)(sui)動(dong)系(xi)(xi)(xi)(xi)統(tong)(tong)(tong)(tong)(tong)，亦(yi)稱(cheng)(cheng)伺服系(xi)(xi)(xi)(xi)統(tong)(tong)(tong)(tong)(tong)。在(zai)(zai)控(kong)(kong)制系(xi)(xi)(xi)(xi)統(tong)(tong)(tong)(tong)(tong)中若給(gei)定(ding)的(de)(de)輸(shu)(shu)(shu)(shu)入(ru)(ru)信號是(shi)預先未(wei)知(zhi)(zhi)且(qie)隨(sui)(sui)時間(jian)變(bian)(bian)化(hua)(hua)(hua)(hua)的(de)(de)并(bing)且(qie)系(xi)(xi)(xi)(xi)統(tong)(tong)(tong)(tong)(tong)的(de)(de)輸(shu)(shu)(shu)(shu)出(chu)量(liang)(liang)(liang)隨(sui)(sui)輸(shu)(shu)(shu)(shu)入(ru)(ru)量(liang)(liang)(liang)的(de)(de)變(bian)(bian)化(hua)(hua)(hua)(hua)而(er)變(bian)(bian)化(hua)(hua)(hua)(hua)這種(zhong)(zhong)系(xi)(xi)(xi)(xi)統(tong)(tong)(tong)(tong)(tong)就稱(cheng)(cheng)為隨(sui)(sui)動(dong)系(xi)(xi)(xi)(xi)統(tong)(tong)(tong)(tong)(tong)。快速(su)跟(gen)蹤和準確(que)定(ding)位(wei)是(shi)隨(sui)(sui)動(dong)系(xi)(xi)(xi)(xi)統(tong)(tong)(tong)(tong)(tong)的(de)(de)兩個重要技術指(zhi)標。
二、隨動系統的特點
改變(bian)電(dian)(dian)(dian)動(dong)機(ji)電(dian)(dian)(dian)樞回路(lu)總電(dian)(dian)(dian)阻調速(su)(su)方法最早被采(cai)用。該調速(su)(su)系(xi)統的特(te)點是：設計、安裝、調試方便(bian)、設備線路(lu)簡單，投資小；缺點是：電(dian)(dian)(dian)動(dong)機(ji)的機(ji)械(xie)特(te)性變(bian)軟(ruan)，耗能多(duo)；調速(su)(su)范圍小，不(bu)平(ping)滑。減(jian)弱(ruo)電(dian)(dian)(dian)動(dong)機(ji)勵磁(ci)磁(ci)通調速(su)(su)方法調速(su)(su)范圍不(bu)大，電(dian)(dian)(dian)動(dong)機(ji)的機(ji)械(xie)特(te)性變(bian)軟(ruan)，只(zhi)要求(qiu)在額(e)定轉速(su)(su)以上升速(su)(su)時采(cai)用。
改變(bian)電動(dong)機的(de)端電壓(ya)的(de)調速方(fang)法調速系統調速范圍大、平滑性好。常采用的(de)調壓(ya)調速方(fang)法是：采用晶閘管(guan)可控整流裝置(zhi)供電給(gei)直流電動(dong)機的(de)調速系統。
三、隨動系統的基本形式
1、轉速負反饋調速系統的組成、原理及其靜特性
由直流電(dian)動機的(de)(de)(de)特性(xing)方(fang)程可知，電(dian)動機轉速隨著負載(zai)增(zeng)加而(er)下(xia)降(jiang)的(de)(de)(de)原因是由于電(dian)樞回路電(dian)壓降(jiang)增(zeng)大之故。如果能夠做(zuo)到(dao)隨著負載(zai)增(zeng)加轉速有(you)所下(xia)降(jiang)時(shi)及時(shi)調整晶閘管(guan)的(de)(de)(de)控(kong)制角(jiao)，提(ti)高(gao)整流電(dian)源(yuan)的(de)(de)(de)輸出(chu)電(dian)壓，電(dian)動機的(de)(de)(de)轉速就會有(you)一(yi)定的(de)(de)(de)回升。這就必須依靠轉速的(de)(de)(de)閉(bi)環控(kong)制。
2、調速系統的靜特性
分析(xi)系統(tong)穩態(tai)特性的目的，就是要找出減(jian)少靜態(tai)速(su)降，擴大調(diao)速(su)范圍的途(tu)徑，改善系統(tong)的調(diao)速(su)性能。
