一(yi)、概述(shu)
交流(liu)鼠(shu)籠式(shi)異步電(dian)(dian)動(dong)(dong)機如果直接起動(dong)(dong)會產(chan)生很大沖(chong)擊(ji)電(dian)(dian)流(liu)，會對電(dian)(dian)阻及其負載造成沖(chong)擊(ji)，甚至危害電(dian)(dian)網安全運行。生產(chan)機械(xie)對電(dian)(dian)動(dong)(dong)機的(de)起動(dong)(dong)也有(you)各種不同的(de)要求，有(you)些(xie)需(xu)要平穩(wen)起動(dong)(dong)的(de)生產(chan)機械(xie)也不允許直接起動(dong)(dong)。
星-三角轉換(huan)(huan)起動，自藕變壓(ya)器降(jiang)(jiang)壓(ya)起動的(de)主(zhu)要問題是起動過程(cheng)中(zhong)起動電壓(ya)和(he)運行電壓(ya)轉換(huan)(huan)時的(de)電流沖擊(ji)，對電網和(he)機械產(chan)生沖擊(ji)，產(chan)生損害。應(ying)用晶閘管交(jiao)流調壓(ya)技術的(de)固態軟起動器，是目前降(jiang)(jiang)壓(ya)起動方(fang)(fang)式中(zhong)合理(li)、先進的(de)起動方(fang)(fang)式。
二、工作原理
軟啟動調(diao)(diao)(diao)速實際(ji)上是—個(ge)(ge)晶(jing)閘(zha)管(guan)(guan)(guan)交流(liu)調(diao)(diao)(diao)壓(ya)(ya)(ya)(ya)(ya)(ya)器(qi)。改變晶(jing)閘(zha)管(guan)(guan)(guan)的(de)觸發角(jiao)，就可調(diao)(diao)(diao)節晶(jing)閘(zha)管(guan)(guan)(guan)調(diao)(diao)(diao)壓(ya)(ya)(ya)(ya)(ya)(ya)電(dian)(dian)路(lu)的(de)輸出(chu)電(dian)(dian)壓(ya)(ya)(ya)(ya)(ya)(ya)。用軟(ruan)起動器(qi)起動電(dian)(dian)機時：設(she)(she)置(zhi)(zhi)一(yi)(yi)個(ge)(ge)初(chu)始(shi)電(dian)(dian)壓(ya)(ya)(ya)(ya)(ya)(ya)，晶(jing)閘(zha)管(guan)(guan)(guan)調(diao)(diao)(diao)壓(ya)(ya)(ya)(ya)(ya)(ya)電(dian)(dian)路(lu)的(de)輸出(chu)電(dian)(dian)壓(ya)(ya)(ya)(ya)(ya)(ya)就從這(zhe)一(yi)(yi)點(dian)開始(shi)上升；設(she)(she)置(zhi)(zhi)一(yi)(yi)個(ge)(ge)升壓(ya)(ya)(ya)(ya)(ya)(ya)時間，逐(zhu)漸(jian)增加晶(jing)閘(zha)管(guan)(guan)(guan)調(diao)(diao)(diao)壓(ya)(ya)(ya)(ya)(ya)(ya)電(dian)(dian)路(lu)的(de)輸出(chu)電(dian)(dian)壓(ya)(ya)(ya)(ya)(ya)(ya)，電(dian)(dian)機逐(zhu)漸(jian)加速；設(she)(she)置(zhi)(zhi)—個(ge)(ge)限流(liu)倍數，根據電(dian)(dian)流(liu)互(hu)感器(qi)測得的(de)實際(ji)電(dian)(dian)流(liu)值，控制晶(jing)閘(zha)管(guan)(guan)(guan)調(diao)(diao)(diao)壓(ya)(ya)(ya)(ya)(ya)(ya)電(dian)(dian)路(lu)的(de)輸出(chu)電(dian)(dian)壓(ya)(ya)(ya)(ya)(ya)(ya)，使電(dian)(dian)機的(de)實際(ji)電(dian)(dian)流(liu)不超過限流(liu)值。這(zhe)樣在(zai)整個(ge)(ge)起動過程中，軟(ruan)啟動柜的(de)輸出(chu)是一(yi)(yi)個(ge)(ge)平滑(hua)的(de)升壓(ya)(ya)(ya)(ya)(ya)(ya)過程（且具有限流(liu)功(gong)能），直(zhi)到晶(jing)閘(zha)管(guan)(guan)(guan)全導通，電(dian)(dian)機在(zai)額定(ding)電(dian)(dian)壓(ya)(ya)(ya)(ya)(ya)(ya)下(xia)工作。

典型應用簡(jian)介
水泵：利用泵控制功能，在起動和停止(zhi)時，減少液(ye)流沖擊所產生的泵流水錘(chui)現象，節省了(le)系統維修費用； 
球磨(mo)(mo)機：利用電壓(ya)斜坡起動，減(jian)少齒輪轉矩的磨(mo)(mo)損(sun)，減(jian)少維修工(gong)作量延長使用壽命； 
風機：利(li)用(yong)固態軟起(qi)(qi)動器(qi)取代了傳(chuan)統起(qi)(qi)動器(qi)，減少皮帶磨損(sun)和機械沖擊(ji)； 
壓縮機：利用限流(liu)，實(shi)現了平滑起動(dong)，降(jiang)低電機溫升； 
破碎機：利用(yong)堵(du)轉保護和(he)快速(su)保護，避免機械故障和(he)阻塞造(zao)成電動機過熱而燒毀； 
輸送機械：利用(yong)軟起動和軟停機控制，實(shi)現(xian)平(ping)滑(hua)漸進的起動過程和平(ping)滑(hua)減速(su)的停車過程，避免了(le)因沖擊而(er)對物料(liao)和設備造成的損傷(shang).