一(yi)、概(gai)述
交流鼠籠式異步(bu)電(dian)動(dong)機如(ru)果直接(jie)起(qi)動(dong)會產(chan)生很大沖(chong)擊電(dian)流，會對(dui)(dui)電(dian)阻(zu)及其負載(zai)造成(cheng)沖(chong)擊，甚至危(wei)害電(dian)網安全運行。生產(chan)機械對(dui)(dui)電(dian)動(dong)機的(de)起(qi)動(dong)也有各種不同的(de)要求，有些需要平穩起(qi)動(dong)的(de)生產(chan)機械也不允許(xu)直接(jie)起(qi)動(dong)。
星-三角轉換起(qi)(qi)(qi)(qi)動(dong)(dong)，自藕變壓器(qi)降壓起(qi)(qi)(qi)(qi)動(dong)(dong)的(de)主要問題是起(qi)(qi)(qi)(qi)動(dong)(dong)過程中起(qi)(qi)(qi)(qi)動(dong)(dong)電(dian)壓和運行電(dian)壓轉換時的(de)電(dian)流(liu)沖(chong)擊，對電(dian)網和機械產生沖(chong)擊，產生損(sun)害。應用晶閘管交流(liu)調壓技術的(de)固(gu)態軟起(qi)(qi)(qi)(qi)動(dong)(dong)器(qi)，是目前降壓起(qi)(qi)(qi)(qi)動(dong)(dong)方式(shi)中合理(li)、先進(jin)的(de)起(qi)(qi)(qi)(qi)動(dong)(dong)方式(shi)。
二、工作原(yuan)理
軟啟(qi)動調(diao)速(su)實(shi)(shi)際(ji)(ji)上是—個晶(jing)(jing)閘(zha)管(guan)交流(liu)(liu)調(diao)壓(ya)(ya)(ya)器。改變晶(jing)(jing)閘(zha)管(guan)的觸發(fa)角，就(jiu)可(ke)調(diao)節晶(jing)(jing)閘(zha)管(guan)調(diao)壓(ya)(ya)(ya)電(dian)(dian)(dian)(dian)(dian)路(lu)的輸出(chu)電(dian)(dian)(dian)(dian)(dian)壓(ya)(ya)(ya)。用軟起動(dong)器起動(dong)電(dian)(dian)(dian)(dian)(dian)機(ji)時(shi)：設置(zhi)一個初(chu)始電(dian)(dian)(dian)(dian)(dian)壓(ya)(ya)(ya)，晶(jing)(jing)閘(zha)管(guan)調(diao)壓(ya)(ya)(ya)電(dian)(dian)(dian)(dian)(dian)路(lu)的輸出(chu)電(dian)(dian)(dian)(dian)(dian)壓(ya)(ya)(ya)就(jiu)從這一點開始上升(sheng)；設置(zhi)一個升(sheng)壓(ya)(ya)(ya)時(shi)間，逐漸增加晶(jing)(jing)閘(zha)管(guan)調(diao)壓(ya)(ya)(ya)電(dian)(dian)(dian)(dian)(dian)路(lu)的輸出(chu)電(dian)(dian)(dian)(dian)(dian)壓(ya)(ya)(ya)，電(dian)(dian)(dian)(dian)(dian)機(ji)逐漸加速(su)；設置(zhi)—個限(xian)(xian)流(liu)(liu)倍(bei)數，根據電(dian)(dian)(dian)(dian)(dian)流(liu)(liu)互(hu)感器測得的實(shi)(shi)際(ji)(ji)電(dian)(dian)(dian)(dian)(dian)流(liu)(liu)值，控制晶(jing)(jing)閘(zha)管(guan)調(diao)壓(ya)(ya)(ya)電(dian)(dian)(dian)(dian)(dian)路(lu)的輸出(chu)電(dian)(dian)(dian)(dian)(dian)壓(ya)(ya)(ya)，使電(dian)(dian)(dian)(dian)(dian)機(ji)的實(shi)(shi)際(ji)(ji)電(dian)(dian)(dian)(dian)(dian)流(liu)(liu)不(bu)超過限(xian)(xian)流(liu)(liu)值。這樣在(zai)整(zheng)個起動(dong)過程(cheng)中(zhong)，軟啟動(dong)柜的輸出(chu)是一個平滑的升(sheng)壓(ya)(ya)(ya)過程(cheng)（且具有限(xian)(xian)流(liu)(liu)功(gong)能(neng)），直到晶(jing)(jing)閘(zha)管(guan)全(quan)導通，電(dian)(dian)(dian)(dian)(dian)機(ji)在(zai)額定電(dian)(dian)(dian)(dian)(dian)壓(ya)(ya)(ya)下工作。

典型應用(yong)簡介
水(shui)泵：利用泵控制功能(neng)，在起動和停止時，減少液(ye)流沖擊所產生(sheng)的泵流水(shui)錘(chui)現象，節省了系統維修費用； 
球磨機：利用電壓斜坡起(qi)動，減少(shao)齒輪轉(zhuan)矩(ju)的磨損(sun)，減少(shao)維修工作量延長使用壽命； 
風機(ji)：利(li)用固態軟起動器(qi)取代了傳統起動器(qi)，減少皮帶(dai)磨損和機(ji)械沖擊； 
壓縮機：利用限(xian)流，實現了平滑起動(dong)，降(jiang)低電機溫升； 
破碎(sui)機(ji)：利(li)用堵(du)轉(zhuan)保(bao)護(hu)(hu)和快速保(bao)護(hu)(hu)，避免機(ji)械故障和阻塞造成(cheng)電動機(ji)過熱而(er)燒毀； 
輸送機械(xie)：利用軟起動(dong)(dong)和軟停機控制，實現平滑漸(jian)進的起動(dong)(dong)過程和平滑減(jian)速的停車過程，避免(mian)了因沖擊而對物料和設(she)備造成的損傷.