一、概述
交(jiao)流(liu)鼠(shu)籠式異步(bu)電(dian)動(dong)機(ji)如(ru)果直接(jie)起(qi)(qi)(qi)動(dong)會(hui)產生很大沖擊電(dian)流(liu)，會(hui)對電(dian)阻(zu)及其負載(zai)造成沖擊，甚至危(wei)害電(dian)網安全(quan)運行。生產機(ji)械對電(dian)動(dong)機(ji)的起(qi)(qi)(qi)動(dong)也有(you)各種不同的要(yao)求，有(you)些需要(yao)平穩(wen)起(qi)(qi)(qi)動(dong)的生產機(ji)械也不允許直接(jie)起(qi)(qi)(qi)動(dong)。
星-三角(jiao)轉(zhuan)換(huan)起(qi)(qi)(qi)動(dong)(dong)，自藕變壓器降壓起(qi)(qi)(qi)動(dong)(dong)的(de)(de)主要問題(ti)是起(qi)(qi)(qi)動(dong)(dong)過程中起(qi)(qi)(qi)動(dong)(dong)電(dian)(dian)壓和運行電(dian)(dian)壓轉(zhuan)換(huan)時的(de)(de)電(dian)(dian)流沖(chong)擊，對電(dian)(dian)網和機械產生沖(chong)擊，產生損害。應用晶閘管交流調壓技(ji)術的(de)(de)固(gu)態(tai)軟起(qi)(qi)(qi)動(dong)(dong)器，是目前降壓起(qi)(qi)(qi)動(dong)(dong)方式(shi)中合理、先進的(de)(de)起(qi)(qi)(qi)動(dong)(dong)方式(shi)。
二、工作原理(li)
軟啟動調(diao)(diao)速實(shi)際上是—個(ge)(ge)晶閘(zha)管(guan)(guan)(guan)交(jiao)流調(diao)(diao)壓(ya)(ya)器。改變晶閘(zha)管(guan)(guan)(guan)的觸發角(jiao)，就可調(diao)(diao)節晶閘(zha)管(guan)(guan)(guan)調(diao)(diao)壓(ya)(ya)電(dian)(dian)(dian)(dian)路的輸(shu)出(chu)電(dian)(dian)(dian)(dian)壓(ya)(ya)。用軟起動(dong)(dong)器起動(dong)(dong)電(dian)(dian)(dian)(dian)機時：設置一個(ge)(ge)初始電(dian)(dian)(dian)(dian)壓(ya)(ya)，晶閘(zha)管(guan)(guan)(guan)調(diao)(diao)壓(ya)(ya)電(dian)(dian)(dian)(dian)路的輸(shu)出(chu)電(dian)(dian)(dian)(dian)壓(ya)(ya)就從這(zhe)一點開始上升(sheng)；設置一個(ge)(ge)升(sheng)壓(ya)(ya)時間，逐漸增(zeng)加晶閘(zha)管(guan)(guan)(guan)調(diao)(diao)壓(ya)(ya)電(dian)(dian)(dian)(dian)路的輸(shu)出(chu)電(dian)(dian)(dian)(dian)壓(ya)(ya)，電(dian)(dian)(dian)(dian)機逐漸加速；設置—個(ge)(ge)限流倍數，根據電(dian)(dian)(dian)(dian)流互感(gan)器測得的實(shi)際電(dian)(dian)(dian)(dian)流值(zhi)，控(kong)制(zhi)晶閘(zha)管(guan)(guan)(guan)調(diao)(diao)壓(ya)(ya)電(dian)(dian)(dian)(dian)路的輸(shu)出(chu)電(dian)(dian)(dian)(dian)壓(ya)(ya)，使電(dian)(dian)(dian)(dian)機的實(shi)際電(dian)(dian)(dian)(dian)流不超過(guo)限流值(zhi)。這(zhe)樣在整(zheng)個(ge)(ge)起動(dong)(dong)過(guo)程(cheng)中，軟啟(qi)動(dong)(dong)柜的輸(shu)出(chu)是一個(ge)(ge)平(ping)滑的升(sheng)壓(ya)(ya)過(guo)程(cheng)（且具有限流功能），直到晶閘(zha)管(guan)(guan)(guan)全導通，電(dian)(dian)(dian)(dian)機在額定(ding)電(dian)(dian)(dian)(dian)壓(ya)(ya)下工作。

典型(xing)應用簡介
水泵(beng)(beng)：利用泵(beng)(beng)控制(zhi)功能，在起動(dong)和停止時(shi)，減少液流(liu)沖擊所產生的泵(beng)(beng)流(liu)水錘現象，節(jie)省了系統維修(xiu)費(fei)用； 
球磨(mo)機：利(li)用電壓斜坡起動，減少齒輪轉矩的磨(mo)損(sun)，減少維修工(gong)作量延長使用壽命； 
風機(ji)：利用固態軟起(qi)動器取代了傳統起(qi)動器，減少(shao)皮帶(dai)磨損和機(ji)械沖擊； 
壓縮機：利用(yong)限流，實現了(le)平滑起(qi)動，降(jiang)低電機溫(wen)升； 
破碎機：利用堵轉保護(hu)和快速保護(hu)，避免機械故障(zhang)和阻塞造成電動(dong)機過熱而燒毀； 
輸送機械：利(li)用軟(ruan)(ruan)起(qi)動和軟(ruan)(ruan)停(ting)機控制，實現平滑(hua)(hua)漸進的起(qi)動過程和平滑(hua)(hua)減(jian)速的停(ting)車過程，避免了因(yin)沖擊而對物料和設備造成的損傷.