一、概述
交流(liu)鼠籠式異(yi)步電(dian)動(dong)機如果直(zhi)接(jie)起(qi)動(dong)會產(chan)生很大沖(chong)擊電(dian)流(liu)，會對(dui)電(dian)阻(zu)及其負載造成沖(chong)擊，甚至危害電(dian)網安(an)全運行。生產(chan)機械(xie)(xie)對(dui)電(dian)動(dong)機的(de)起(qi)動(dong)也有各種不(bu)同(tong)的(de)要求，有些需要平穩(wen)起(qi)動(dong)的(de)生產(chan)機械(xie)(xie)也不(bu)允許直(zhi)接(jie)起(qi)動(dong)。
星-三角轉(zhuan)換起(qi)動，自(zi)藕變壓(ya)器降壓(ya)起(qi)動的(de)主要問(wen)題是(shi)起(qi)動過程中起(qi)動電壓(ya)和運行電壓(ya)轉(zhuan)換時的(de)電流(liu)沖(chong)擊(ji)，對電網和機械(xie)產生(sheng)沖(chong)擊(ji)，產生(sheng)損害。應用晶閘(zha)管交流(liu)調(diao)壓(ya)技術的(de)固態軟起(qi)動器，是(shi)目前(qian)降壓(ya)起(qi)動方(fang)式(shi)中合理、先進的(de)起(qi)動方(fang)式(shi)。
二、工(gong)作原理
軟啟動調(diao)速實(shi)際上(shang)(shang)是(shi)—個(ge)晶閘管交流(liu)(liu)調(diao)壓(ya)(ya)(ya)(ya)器。改變晶閘管的(de)觸發(fa)角，就(jiu)可(ke)調(diao)節(jie)晶閘管調(diao)壓(ya)(ya)(ya)(ya)電(dian)(dian)(dian)路(lu)的(de)輸出電(dian)(dian)(dian)壓(ya)(ya)(ya)(ya)。用軟(ruan)起動(dong)(dong)器起動(dong)(dong)電(dian)(dian)(dian)機(ji)(ji)(ji)時(shi)：設(she)置(zhi)(zhi)一個(ge)初(chu)始電(dian)(dian)(dian)壓(ya)(ya)(ya)(ya)，晶閘管調(diao)壓(ya)(ya)(ya)(ya)電(dian)(dian)(dian)路(lu)的(de)輸出電(dian)(dian)(dian)壓(ya)(ya)(ya)(ya)就(jiu)從(cong)這一點開(kai)始上(shang)(shang)升；設(she)置(zhi)(zhi)一個(ge)升壓(ya)(ya)(ya)(ya)時(shi)間(jian)，逐漸(jian)增加晶閘管調(diao)壓(ya)(ya)(ya)(ya)電(dian)(dian)(dian)路(lu)的(de)輸出電(dian)(dian)(dian)壓(ya)(ya)(ya)(ya)，電(dian)(dian)(dian)機(ji)(ji)(ji)逐漸(jian)加速；設(she)置(zhi)(zhi)—個(ge)限(xian)(xian)流(liu)(liu)倍數，根據電(dian)(dian)(dian)流(liu)(liu)互感器測(ce)得(de)的(de)實(shi)際電(dian)(dian)(dian)流(liu)(liu)值，控制晶閘管調(diao)壓(ya)(ya)(ya)(ya)電(dian)(dian)(dian)路(lu)的(de)輸出電(dian)(dian)(dian)壓(ya)(ya)(ya)(ya)，使電(dian)(dian)(dian)機(ji)(ji)(ji)的(de)實(shi)際電(dian)(dian)(dian)流(liu)(liu)不超(chao)過限(xian)(xian)流(liu)(liu)值。這樣在(zai)整個(ge)起動(dong)(dong)過程(cheng)(cheng)中，軟(ruan)啟(qi)動(dong)(dong)柜(ju)的(de)輸出是(shi)一個(ge)平滑的(de)升壓(ya)(ya)(ya)(ya)過程(cheng)(cheng)（且具有限(xian)(xian)流(liu)(liu)功(gong)能），直到晶閘管全(quan)導通，電(dian)(dian)(dian)機(ji)(ji)(ji)在(zai)額定電(dian)(dian)(dian)壓(ya)(ya)(ya)(ya)下工(gong)作(zuo)。

典(dian)型應用(yong)簡介(jie)
水泵：利用(yong)泵控制功能(neng)，在起動和(he)停止時，減(jian)少液流沖擊所產生的泵流水錘現象，節省了系(xi)統維修(xiu)費用(yong)； 
球磨機(ji)：利用電壓斜坡(po)起(qi)動(dong)，減少(shao)(shao)齒輪轉矩(ju)的磨損(sun)，減少(shao)(shao)維修工作量延(yan)長使用壽命； 
風(feng)機(ji)：利(li)用(yong)固態軟起動器取代了傳統起動器，減(jian)少皮(pi)帶磨(mo)損和(he)機(ji)械(xie)沖擊； 
壓縮機：利用限流，實現了平滑(hua)起動，降低電機溫(wen)升； 
破碎機(ji)：利用堵轉保護(hu)和快速(su)保護(hu)，避免機(ji)械故(gu)障和阻塞造成電動(dong)機(ji)過(guo)熱而燒毀； 
輸送機械：利(li)用(yong)軟起(qi)動和(he)軟停(ting)機控制，實(shi)現平滑漸進的起(qi)動過程和(he)平滑減(jian)速的停(ting)車(che)過程，避(bi)免了因(yin)沖擊而(er)對物(wu)料和(he)設備造(zao)成的損傷.