一、概述
交流鼠(shu)籠(long)式異(yi)步電(dian)動(dong)(dong)機如果(guo)直接(jie)起(qi)動(dong)(dong)會產(chan)(chan)生(sheng)(sheng)很大沖擊(ji)電(dian)流，會對(dui)電(dian)阻及其(qi)負(fu)載造成(cheng)沖擊(ji)，甚至危害(hai)電(dian)網安全運行(xing)。生(sheng)(sheng)產(chan)(chan)機械對(dui)電(dian)動(dong)(dong)機的(de)起(qi)動(dong)(dong)也有各種(zhong)不(bu)同的(de)要求，有些需(xu)要平穩起(qi)動(dong)(dong)的(de)生(sheng)(sheng)產(chan)(chan)機械也不(bu)允許直接(jie)起(qi)動(dong)(dong)。
星-三角(jiao)轉(zhuan)(zhuan)換起(qi)動(dong)(dong)(dong)，自藕變壓(ya)(ya)器降壓(ya)(ya)起(qi)動(dong)(dong)(dong)的(de)(de)主要問(wen)題是起(qi)動(dong)(dong)(dong)過程中(zhong)(zhong)起(qi)動(dong)(dong)(dong)電壓(ya)(ya)和(he)運行電壓(ya)(ya)轉(zhuan)(zhuan)換時的(de)(de)電流(liu)沖擊，對電網和(he)機械產(chan)生沖擊，產(chan)生損害。應用晶閘管交流(liu)調壓(ya)(ya)技術的(de)(de)固(gu)態軟起(qi)動(dong)(dong)(dong)器，是目前降壓(ya)(ya)起(qi)動(dong)(dong)(dong)方式中(zhong)(zhong)合理、先進(jin)的(de)(de)起(qi)動(dong)(dong)(dong)方式。
二、工作原理(li)
軟啟動調速(su)實(shi)際(ji)上是—個晶(jing)(jing)閘(zha)(zha)管(guan)(guan)(guan)交(jiao)流(liu)(liu)調壓(ya)器。改變(bian)晶(jing)(jing)閘(zha)(zha)管(guan)(guan)(guan)的(de)(de)觸(chu)發角，就(jiu)(jiu)可調節晶(jing)(jing)閘(zha)(zha)管(guan)(guan)(guan)調壓(ya)電(dian)(dian)路的(de)(de)輸(shu)(shu)出(chu)(chu)電(dian)(dian)壓(ya)。用軟(ruan)起動(dong)(dong)(dong)器起動(dong)(dong)(dong)電(dian)(dian)機時(shi)：設置(zhi)一(yi)個初(chu)始電(dian)(dian)壓(ya)，晶(jing)(jing)閘(zha)(zha)管(guan)(guan)(guan)調壓(ya)電(dian)(dian)路的(de)(de)輸(shu)(shu)出(chu)(chu)電(dian)(dian)壓(ya)就(jiu)(jiu)從這一(yi)點(dian)開(kai)始上升(sheng)(sheng)；設置(zhi)一(yi)個升(sheng)(sheng)壓(ya)時(shi)間(jian)，逐漸增(zeng)加晶(jing)(jing)閘(zha)(zha)管(guan)(guan)(guan)調壓(ya)電(dian)(dian)路的(de)(de)輸(shu)(shu)出(chu)(chu)電(dian)(dian)壓(ya)，電(dian)(dian)機逐漸加速(su)；設置(zhi)—個限(xian)(xian)流(liu)(liu)倍數，根據電(dian)(dian)流(liu)(liu)互感器測得的(de)(de)實(shi)際(ji)電(dian)(dian)流(liu)(liu)值(zhi)，控制晶(jing)(jing)閘(zha)(zha)管(guan)(guan)(guan)調壓(ya)電(dian)(dian)路的(de)(de)輸(shu)(shu)出(chu)(chu)電(dian)(dian)壓(ya)，使電(dian)(dian)機的(de)(de)實(shi)際(ji)電(dian)(dian)流(liu)(liu)不超過限(xian)(xian)流(liu)(liu)值(zhi)。這樣在整個起動(dong)(dong)(dong)過程(cheng)中，軟(ruan)啟動(dong)(dong)(dong)柜的(de)(de)輸(shu)(shu)出(chu)(chu)是一(yi)個平滑的(de)(de)升(sheng)(sheng)壓(ya)過程(cheng)（且(qie)具有限(xian)(xian)流(liu)(liu)功能），直到晶(jing)(jing)閘(zha)(zha)管(guan)(guan)(guan)全導通，電(dian)(dian)機在額(e)定電(dian)(dian)壓(ya)下工作。

典型應用簡介
水泵：利(li)用泵控制功能，在(zai)起動(dong)和(he)停(ting)止時，減(jian)少液流沖擊所產生(sheng)的泵流水錘現象(xiang)，節(jie)省了系統維修(xiu)費用； 
球磨機：利用(yong)電(dian)壓斜(xie)坡起(qi)動，減(jian)少齒輪轉矩的磨損，減(jian)少維(wei)修工作(zuo)量(liang)延長使用(yong)壽命； 
風機：利用固態軟起動(dong)器取代了(le)傳(chuan)統起動(dong)器，減少皮帶磨(mo)損和機械沖(chong)擊； 
壓縮機：利用限流(liu)，實現了平(ping)滑起動，降低電機溫(wen)升(sheng)； 
破碎機(ji)：利用堵轉保護和(he)(he)快速保護，避(bi)免機(ji)械故障和(he)(he)阻塞造成電動機(ji)過熱而(er)燒毀； 
輸送機械：利用軟(ruan)起動和軟(ruan)停機控制，實(shi)現平(ping)(ping)滑(hua)漸進的(de)起動過程(cheng)和平(ping)(ping)滑(hua)減速的(de)停車(che)過程(cheng)，避免了因沖擊而對物料和設(she)備造(zao)成的(de)損傷.