低壓無功(gong)補(bu)(bu)償(chang)(chang)柜(ju)中低壓智(zhi)能(neng)無功(gong)補(bu)(bu)償(chang)(chang)控制(zhi)器作用(yong)，是為了保證整(zheng)個回(hui)路(lu)安全可靠的(de)(de)運行，以達到無功(gong)補(bu)(bu)償(chang)(chang)的(de)(de)目的(de)(de)，那么電容器(和串(chuan)聯電抗器)作為補(bu)(bu)償(chang)(chang)回(hui)路(lu)的(de)(de)核心元件，熔斷器對它提供(gong)可靠的(de)(de)保護性能(neng)是非(fei)常必要(yao)的(de)(de)。

　　由于現(xian)行相關標準里對補償回路保護熔(rong)斷器(qi)的(de)選擇沒有特別(bie)詳細的(de)要(yao)求，所(suo)以在實際應(ying)用中(zhong)大家的(de)選擇也不盡(jin)一致，有時差別(bie)甚至相當懸(xuan)殊(shu)。

　　在(zai)低壓(ya)配電系(xi)統中的負載類(lei)型變得越(yue)來(lai)越(yue)復雜的情(qing)況下，補償回路熔斷(duan)器的選擇不能一(yi)概而論，要視(shi)低壓(ya)無功補償的具體類(lei)型進行(xing)科學的分析和(he)選擇。

由于(yu)這種(zhong)應(ying)用(yong)的(de)(de)(de)電(dian)(dian)(dian)(dian)(dian)容器額(e)定電(dian)(dian)(dian)(dian)(dian)壓要遠大(da)于(yu)配電(dian)(dian)(dian)(dian)(dian)系統(tong)電(dian)(dian)(dian)(dian)(dian)壓(如14%電(dian)(dian)(dian)(dian)(dian)抗率應(ying)用(yong)時，電(dian)(dian)(dian)(dian)(dian)容器額(e)定電(dian)(dian)(dian)(dian)(dian)壓為525V，遠大(da)于(yu)400V系統(tong)電(dian)(dian)(dian)(dian)(dian)壓)，電(dian)(dian)(dian)(dian)(dian)容器在(zai)400V系統(tong)中實(shi)際能夠承載(zai)的(de)(de)(de)電(dian)(dian)(dian)(dian)(dian)流(liu)(liu)(包括基波(bo)和諧波(bo)電(dian)(dian)(dian)(dian)(dian)流(liu)(liu))要大(da)于(yu)其在(zai)額(e)定電(dian)(dian)(dian)(dian)(dian)壓下(xia)(如525V)的(de)(de)(de)額(e)定電(dian)(dian)(dian)(dian)(dian)流(liu)(liu)。因(yin)此，在(zai)這種(zhong)無功補償應(ying)用(yong)中，決定回路過(guo)載(zai)能力的(de)(de)(de)是串聯電(dian)(dian)(dian)(dian)(dian)抗器的(de)(de)(de)參數(shu)，即電(dian)(dian)(dian)(dian)(dian)抗器的(de)(de)(de)大(da)過(guo)電(dian)(dian)(dian)(dian)(dian)流(liu)(liu)能力。

　　所以熔斷器的(de)選(xuan)擇應該以回(hui)路(lu)的(de)額定電流(liu)(liu)和電抗(kang)器的(de)大過電流(liu)(liu)能力(li)為依據。以電抗(kang)率為14%的(de)25KVAR/400V的(de)補償回(hui)路(lu)舉例(li)分析：

　　該回(hui)路的(de)(de)(de)電(dian)(dian)(dian)容器額定(ding)(ding)電(dian)(dian)(dian)流為(wei)36A，如果電(dian)(dian)(dian)抗(kang)器的(de)(de)(de)大(da)過電(dian)(dian)(dian)流能力為(wei)1.8倍(bei)的(de)(de)(de)額定(ding)(ding)電(dian)(dian)(dian)流，則該回(hui)路的(de)(de)(de)大(da)允許電(dian)(dian)(dian)流為(wei)1.8×36=64.8A，因此正確的(de)(de)(de)熔斷器的(de)(de)(de)額定(ding)(ding)保護電(dian)(dian)(dian)流應為(wei)63A。