一(yi)、概述
交流鼠籠(long)式異步(bu)電(dian)動(dong)機(ji)如果(guo)直接(jie)起(qi)動(dong)會產(chan)生很大沖擊電(dian)流，會對(dui)電(dian)阻(zu)及其(qi)負(fu)載造成沖擊，甚至危害電(dian)網安全運行。生產(chan)機(ji)械(xie)對(dui)電(dian)動(dong)機(ji)的起(qi)動(dong)也有各種不同的要求，有些需要平穩起(qi)動(dong)的生產(chan)機(ji)械(xie)也不允(yun)許直接(jie)起(qi)動(dong)。
星-三角(jiao)轉換起(qi)動(dong)(dong)，自藕變(bian)壓器降壓起(qi)動(dong)(dong)的(de)主要問題是起(qi)動(dong)(dong)過(guo)程(cheng)中(zhong)(zhong)起(qi)動(dong)(dong)電(dian)壓和運(yun)行電(dian)壓轉換時的(de)電(dian)流沖擊，對電(dian)網和機械產生沖擊，產生損害。應用晶閘管交流調壓技術(shu)的(de)固(gu)態軟起(qi)動(dong)(dong)器，是目(mu)前降壓起(qi)動(dong)(dong)方式(shi)中(zhong)(zhong)合理、先(xian)進的(de)起(qi)動(dong)(dong)方式(shi)。
二、工作(zuo)原理(li)
軟啟動調(diao)速實(shi)際上(shang)是—個(ge)(ge)(ge)(ge)晶(jing)(jing)(jing)(jing)閘管交流(liu)調(diao)壓(ya)(ya)器。改變晶(jing)(jing)(jing)(jing)閘管的觸發角，就(jiu)可調(diao)節晶(jing)(jing)(jing)(jing)閘管調(diao)壓(ya)(ya)電(dian)(dian)(dian)(dian)路(lu)的輸出(chu)(chu)電(dian)(dian)(dian)(dian)壓(ya)(ya)。用軟起動器起動電(dian)(dian)(dian)(dian)機(ji)時：設置(zhi)一(yi)個(ge)(ge)(ge)(ge)初始(shi)(shi)電(dian)(dian)(dian)(dian)壓(ya)(ya)，晶(jing)(jing)(jing)(jing)閘管調(diao)壓(ya)(ya)電(dian)(dian)(dian)(dian)路(lu)的輸出(chu)(chu)電(dian)(dian)(dian)(dian)壓(ya)(ya)就(jiu)從這一(yi)點開始(shi)(shi)上(shang)升；設置(zhi)一(yi)個(ge)(ge)(ge)(ge)升壓(ya)(ya)時間，逐漸增加晶(jing)(jing)(jing)(jing)閘管調(diao)壓(ya)(ya)電(dian)(dian)(dian)(dian)路(lu)的輸出(chu)(chu)電(dian)(dian)(dian)(dian)壓(ya)(ya)，電(dian)(dian)(dian)(dian)機(ji)逐漸加速；設置(zhi)—個(ge)(ge)(ge)(ge)限流(liu)倍數，根據電(dian)(dian)(dian)(dian)流(liu)互感器測得(de)的實(shi)際電(dian)(dian)(dian)(dian)流(liu)值，控制晶(jing)(jing)(jing)(jing)閘管調(diao)壓(ya)(ya)電(dian)(dian)(dian)(dian)路(lu)的輸出(chu)(chu)電(dian)(dian)(dian)(dian)壓(ya)(ya)，使電(dian)(dian)(dian)(dian)機(ji)的實(shi)際電(dian)(dian)(dian)(dian)流(liu)不(bu)超過限流(liu)值。這樣在(zai)(zai)整個(ge)(ge)(ge)(ge)起動過程(cheng)(cheng)中，軟啟動柜的輸出(chu)(chu)是一(yi)個(ge)(ge)(ge)(ge)平滑的升壓(ya)(ya)過程(cheng)(cheng)（且具有限流(liu)功(gong)能），直到晶(jing)(jing)(jing)(jing)閘管全導(dao)通，電(dian)(dian)(dian)(dian)機(ji)在(zai)(zai)額定電(dian)(dian)(dian)(dian)壓(ya)(ya)下工作。

典型應用簡介(jie)
水(shui)泵：利用泵控制功(gong)能，在起動和停止時，減少液流(liu)沖擊所產(chan)生的泵流(liu)水(shui)錘現象，節省(sheng)了(le)系統維修費(fei)用； 
球磨機：利用電壓斜(xie)坡起動，減少齒輪轉矩的磨損(sun)，減少維修工作量延長(chang)使用壽命； 
風機：利(li)用固(gu)態(tai)軟起動器取代了傳統起動器，減少皮帶磨損和機械沖擊； 
壓縮機(ji)：利用限(xian)流(liu)，實現了平滑起(qi)動，降低電(dian)機(ji)溫(wen)升； 
破碎機：利(li)用堵轉(zhuan)保護和快速(su)保護，避免機械故障和阻塞造成電動機過(guo)熱而燒毀； 
輸送機械：利用軟起動(dong)和(he)(he)軟停(ting)機控制，實(shi)現(xian)平(ping)滑漸進的(de)起動(dong)過(guo)程和(he)(he)平(ping)滑減(jian)速的(de)停(ting)車(che)過(guo)程，避免(mian)了因沖擊(ji)而(er)對物料和(he)(he)設備造成的(de)損傷.