一(yi)、概(gai)述
交流鼠籠式(shi)異步電(dian)動(dong)機(ji)如果直接起動(dong)會產生很大沖(chong)擊電(dian)流，會對電(dian)阻(zu)及其負載造(zao)成(cheng)沖(chong)擊，甚至危害(hai)電(dian)網安(an)全運行(xing)。生產機(ji)械對電(dian)動(dong)機(ji)的(de)起動(dong)也有各種不同的(de)要求，有些需要平穩起動(dong)的(de)生產機(ji)械也不允許直接起動(dong)。
星-三角轉換(huan)起(qi)動(dong)，自藕變壓(ya)器(qi)降(jiang)壓(ya)起(qi)動(dong)的(de)主要問題是(shi)起(qi)動(dong)過程(cheng)中起(qi)動(dong)電壓(ya)和運行電壓(ya)轉換(huan)時(shi)的(de)電流(liu)沖擊，對電網和機械(xie)產生沖擊，產生損害。應(ying)用(yong)晶閘管交流(liu)調壓(ya)技術的(de)固(gu)態(tai)軟起(qi)動(dong)器(qi)，是(shi)目(mu)前降(jiang)壓(ya)起(qi)動(dong)方式中合理(li)、先(xian)進的(de)起(qi)動(dong)方式。
二、工作(zuo)原理
軟啟動調(diao)(diao)速實際(ji)上(shang)是(shi)—個(ge)晶閘(zha)管交(jiao)流(liu)(liu)(liu)調(diao)(diao)壓(ya)(ya)(ya)(ya)器(qi)。改變晶閘(zha)管的(de)觸發角，就可調(diao)(diao)節晶閘(zha)管調(diao)(diao)壓(ya)(ya)(ya)(ya)電(dian)(dian)(dian)(dian)路(lu)(lu)的(de)輸(shu)(shu)出(chu)(chu)(chu)電(dian)(dian)(dian)(dian)壓(ya)(ya)(ya)(ya)。用軟起(qi)動(dong)(dong)器(qi)起(qi)動(dong)(dong)電(dian)(dian)(dian)(dian)機(ji)時(shi)：設置(zhi)(zhi)一個(ge)初始電(dian)(dian)(dian)(dian)壓(ya)(ya)(ya)(ya)，晶閘(zha)管調(diao)(diao)壓(ya)(ya)(ya)(ya)電(dian)(dian)(dian)(dian)路(lu)(lu)的(de)輸(shu)(shu)出(chu)(chu)(chu)電(dian)(dian)(dian)(dian)壓(ya)(ya)(ya)(ya)就從這一點開始上(shang)升(sheng)；設置(zhi)(zhi)一個(ge)升(sheng)壓(ya)(ya)(ya)(ya)時(shi)間，逐(zhu)漸增加(jia)晶閘(zha)管調(diao)(diao)壓(ya)(ya)(ya)(ya)電(dian)(dian)(dian)(dian)路(lu)(lu)的(de)輸(shu)(shu)出(chu)(chu)(chu)電(dian)(dian)(dian)(dian)壓(ya)(ya)(ya)(ya)，電(dian)(dian)(dian)(dian)機(ji)逐(zhu)漸加(jia)速；設置(zhi)(zhi)—個(ge)限流(liu)(liu)(liu)倍數，根據電(dian)(dian)(dian)(dian)流(liu)(liu)(liu)互感器(qi)測得(de)的(de)實際(ji)電(dian)(dian)(dian)(dian)流(liu)(liu)(liu)值，控制晶閘(zha)管調(diao)(diao)壓(ya)(ya)(ya)(ya)電(dian)(dian)(dian)(dian)路(lu)(lu)的(de)輸(shu)(shu)出(chu)(chu)(chu)電(dian)(dian)(dian)(dian)壓(ya)(ya)(ya)(ya)，使(shi)電(dian)(dian)(dian)(dian)機(ji)的(de)實際(ji)電(dian)(dian)(dian)(dian)流(liu)(liu)(liu)不超過限流(liu)(liu)(liu)值。這樣在整個(ge)起(qi)動(dong)(dong)過程(cheng)中，軟啟動(dong)(dong)柜的(de)輸(shu)(shu)出(chu)(chu)(chu)是(shi)一個(ge)平滑(hua)的(de)升(sheng)壓(ya)(ya)(ya)(ya)過程(cheng)（且具有限流(liu)(liu)(liu)功(gong)能），直到(dao)晶閘(zha)管全導通(tong)，電(dian)(dian)(dian)(dian)機(ji)在額定電(dian)(dian)(dian)(dian)壓(ya)(ya)(ya)(ya)下工作。

典型(xing)應(ying)用(yong)簡介(jie)
水泵：利用(yong)泵控制功能，在起動(dong)和停(ting)止時，減少(shao)液流沖擊(ji)所(suo)產生(sheng)的(de)泵流水錘現象，節(jie)省了系統維修費用(yong)； 
球磨機：利用電壓(ya)斜坡(po)起動，減(jian)少齒輪(lun)轉矩的磨損，減(jian)少維修工(gong)作量延(yan)長使用壽命(ming)； 
風(feng)機(ji)：利用固態軟起(qi)動(dong)器(qi)取代了傳(chuan)統起(qi)動(dong)器(qi)，減少皮帶磨損(sun)和機(ji)械沖擊； 
壓縮機(ji)：利用限流，實(shi)現(xian)了(le)平(ping)滑(hua)起(qi)動(dong)，降低(di)電(dian)機(ji)溫升； 
破碎機(ji)：利用(yong)堵轉保(bao)護和快速保(bao)護，避免(mian)機(ji)械故障和阻塞(sai)造成電動機(ji)過(guo)熱而燒毀； 
輸送機械：利用軟(ruan)起(qi)動和(he)軟(ruan)停機控制，實現平(ping)滑(hua)漸進的起(qi)動過(guo)程和(he)平(ping)滑(hua)減速的停車過(guo)程，避免了因沖擊而(er)對物(wu)料和(he)設備(bei)造(zao)成的損傷.