影(ying)響防(fang)(fang)爆電(dian)(dian)(dian)機(ji)起動(dong)(dong)電(dian)(dian)(dian)流(liu)(liu)過大的(de)主要原(yuan)(yuan)因，提出(chu)(chu)了增加定子線圈匝數來增大短路(lu)阻抗的(de)措(cuo)施(shi)。問題(ti)的(de)引入(ru)三相異(yi)步電(dian)(dian)(dian)動(dong)(dong)機(ji)的(de)起動(dong)(dong)電(dian)(dian)(dian)流(liu)(liu)，通(tong)常是(shi)額定電(dian)(dian)(dian)流(liu)(liu)的(de)4～7倍，也就是(shi)說，防(fang)(fang)爆電(dian)(dian)(dian)機(ji)的(de)起動(dong)(dong)電(dian)(dian)(dian)流(liu)(liu)和額定電(dian)(dian)(dian)流(liu)(liu)相比，已經(jing)足夠大。那(nei)么，會(hui)不會(hui)出(chu)(chu)現(xian)三相異(yi)步電(dian)(dian)(dian)動(dong)(dong)機(ji)起動(dong)(dong)電(dian)(dian)(dian)流(liu)(liu)過大的(de)故障現(xian)象，某一型號電(dian)(dian)(dian)機(ji)，由(you)于起動(dong)(dong)電(dian)(dian)(dian)流(liu)(liu)過大而(er)被使(shi)用廠家退回。原(yuan)(yuan)因是(shi)起動(dong)(dong)過程(cheng)中，總會(hui)使(shi)保護裝置斷路(lu)器跳(tiao)閘而(er)無法起動(dong)(dong)。

    經分析，主要是因斷路器的整定電流小于電動機的起動電流所致。由于在選用斷路器時，斷路器的整定電流沒能躲過電路中的尖峰電流，即三相異步電動機的起動電流。可改換整定電流大一點的斷路器。

    同一型(xing)號的(de)(de)斷(duan)路(lu)器在(zai)(zai)起(qi)動其(qi)他型(xing)號同功(gong)率或更大功(gong)率的(de)(de)電(dian)機(ji)時(shi)并不跳閘。這就(jiu)說明造成(cheng)斷(duan)路(lu)器跳閘的(de)(de)原因不是(shi)斷(duan)路(lu)器的(de)(de)整定(ding)(ding)(ding)電(dian)流(liu)(liu)太小，而是(shi)電(dian)動機(ji)的(de)(de)起(qi)動電(dian)流(liu)(liu)過(guo)大。增(zeng)加定(ding)(ding)(ding)子(zi)線圈的(de)(de)匝數(shu)，相當于在(zai)(zai)定(ding)(ding)(ding)子(zi)中串電(dian)抗(kang)起(qi)動，可(ke)有(you)效地減小起(qi)動電(dian)流(liu)(liu)。同時(shi)，其(qi)過(guo)載能(neng)力和(he)(he)起(qi)動能(neng)力有(you)所(suo)下降。所(suo)以需要(yao)(yao)通過(guo)試驗來確(que)(que)定(ding)(ding)(ding)經(jing)改進(jin)后的(de)(de)電(dian)動機(ji)其(qi)有(you)關參(can)數(shu)是(shi)否(fou)合適。本(ben)次(ci)試驗主要(yao)(yao)以確(que)(que)定(ding)(ding)(ding)起(qi)動電(dian)流(liu)(liu)是(shi)否(fou)合適、過(guo)載能(neng)力和(he)(he)起(qi)動能(neng)力是(shi)否(fou)夠用，所(suo)以主要(yao)(yao)進(jin)行了堵轉試驗和(he)(he)負載試驗。在(zai)(zai)堵轉試驗中，短路(lu)電(dian)流(liu)(liu)在(zai)(zai)1～3倍的(de)(de)額定(ding)(ding)(ding)電(dian)流(liu)(liu)之間取(qu)值(zhi)。主要(yao)(yao)測了各(ge)相的(de)(de)短路(lu)電(dian)壓、短路(lu)電(dian)流(liu)(liu)和(he)(he)短路(lu)轉矩，從而確(que)(que)定(ding)(ding)(ding)在(zai)(zai)額定(ding)(ding)(ding)電(dian)壓時(shi)的(de)(de)起(qi)動電(dian)流(liu)(liu)和(he)(he)起(qi)動轉矩。