一、概述(shu)
交(jiao)流鼠(shu)籠式異(yi)步電(dian)動(dong)(dong)機(ji)(ji)如果直接起(qi)動(dong)(dong)會(hui)(hui)產生很(hen)大沖(chong)(chong)擊(ji)電(dian)流，會(hui)(hui)對電(dian)阻及其負(fu)載造成沖(chong)(chong)擊(ji)，甚(shen)至危害電(dian)網(wang)安全運行。生產機(ji)(ji)械(xie)對電(dian)動(dong)(dong)機(ji)(ji)的起(qi)動(dong)(dong)也有各種不同(tong)的要(yao)求，有些需要(yao)平穩(wen)起(qi)動(dong)(dong)的生產機(ji)(ji)械(xie)也不允許直接起(qi)動(dong)(dong)。
星-三角轉換(huan)起(qi)動(dong)(dong)(dong)，自藕變壓器(qi)降(jiang)壓起(qi)動(dong)(dong)(dong)的主(zhu)要問題是起(qi)動(dong)(dong)(dong)過程(cheng)中(zhong)起(qi)動(dong)(dong)(dong)電(dian)(dian)壓和運行電(dian)(dian)壓轉換(huan)時的電(dian)(dian)流沖(chong)擊，對電(dian)(dian)網和機械產生(sheng)沖(chong)擊，產生(sheng)損害。應用(yong)晶閘管交(jiao)流調壓技術(shu)的固態軟(ruan)起(qi)動(dong)(dong)(dong)器(qi)，是目前降(jiang)壓起(qi)動(dong)(dong)(dong)方式(shi)中(zhong)合(he)理、先進(jin)的起(qi)動(dong)(dong)(dong)方式(shi)。
二、工作(zuo)原理
軟(ruan)啟動(dong)調(diao)(diao)速實(shi)際(ji)上是—個(ge)晶(jing)(jing)閘(zha)管交流(liu)調(diao)(diao)壓(ya)(ya)(ya)(ya)器。改變晶(jing)(jing)閘(zha)管的(de)(de)觸發角，就(jiu)可調(diao)(diao)節晶(jing)(jing)閘(zha)管調(diao)(diao)壓(ya)(ya)(ya)(ya)電(dian)(dian)(dian)路(lu)(lu)的(de)(de)輸出(chu)電(dian)(dian)(dian)壓(ya)(ya)(ya)(ya)。用軟起(qi)動器起(qi)動電(dian)(dian)(dian)機(ji)時：設置(zhi)一(yi)個(ge)初始電(dian)(dian)(dian)壓(ya)(ya)(ya)(ya)，晶(jing)(jing)閘(zha)管調(diao)(diao)壓(ya)(ya)(ya)(ya)電(dian)(dian)(dian)路(lu)(lu)的(de)(de)輸出(chu)電(dian)(dian)(dian)壓(ya)(ya)(ya)(ya)就(jiu)從這(zhe)一(yi)點開始上升；設置(zhi)一(yi)個(ge)升壓(ya)(ya)(ya)(ya)時間，逐漸增加晶(jing)(jing)閘(zha)管調(diao)(diao)壓(ya)(ya)(ya)(ya)電(dian)(dian)(dian)路(lu)(lu)的(de)(de)輸出(chu)電(dian)(dian)(dian)壓(ya)(ya)(ya)(ya)，電(dian)(dian)(dian)機(ji)逐漸加速；設置(zhi)—個(ge)限流(liu)倍數，根據電(dian)(dian)(dian)流(liu)互感器測得的(de)(de)實(shi)際(ji)電(dian)(dian)(dian)流(liu)值(zhi)，控制晶(jing)(jing)閘(zha)管調(diao)(diao)壓(ya)(ya)(ya)(ya)電(dian)(dian)(dian)路(lu)(lu)的(de)(de)輸出(chu)電(dian)(dian)(dian)壓(ya)(ya)(ya)(ya)，使電(dian)(dian)(dian)機(ji)的(de)(de)實(shi)際(ji)電(dian)(dian)(dian)流(liu)不超過(guo)限流(liu)值(zhi)。這(zhe)樣在整個(ge)起(qi)動過(guo)程中，軟啟動柜(ju)的(de)(de)輸出(chu)是一(yi)個(ge)平滑的(de)(de)升壓(ya)(ya)(ya)(ya)過(guo)程（且具有(you)限流(liu)功(gong)能），直到晶(jing)(jing)閘(zha)管全(quan)導通，電(dian)(dian)(dian)機(ji)在額(e)定(ding)電(dian)(dian)(dian)壓(ya)(ya)(ya)(ya)下(xia)工作。

典型應用簡介
水泵：利(li)用(yong)泵控制功能，在起動和(he)停止(zhi)時(shi)，減少(shao)液流(liu)沖擊所(suo)產(chan)生(sheng)的(de)泵流(liu)水錘現象，節省了系統維(wei)修(xiu)費用(yong)； 
球磨機(ji)：利用電(dian)壓斜坡起(qi)動，減(jian)少(shao)齒(chi)輪轉矩的磨損(sun)，減(jian)少(shao)維修(xiu)工作量延(yan)長使(shi)用壽(shou)命； 
風機：利用固(gu)態(tai)軟起動器(qi)取代了傳統起動器(qi)，減少皮帶磨(mo)損和機械沖(chong)擊(ji)； 
壓縮機(ji)：利用限流，實現了平(ping)滑起動，降(jiang)低(di)電機(ji)溫升； 
破碎機：利用堵轉保護和(he)快速(su)保護，避(bi)免機械故障和(he)阻塞造(zao)成(cheng)電動機過熱而燒毀； 
輸送機械：利用軟起動和(he)軟停(ting)機控制，實現平滑漸進的起動過程和(he)平滑減速的停(ting)車過程，避(bi)免(mian)了因(yin)沖擊(ji)而對物料和(he)設備造(zao)成的損傷.