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線(xian)芯線(xian)芯是(shi)(shi)電(dian)(dian)(dian)(dian)力(li)電(dian)(dian)(dian)(dian)纜的(de)(de)導電(dian)(dian)(dian)(dian)部分(fen)，用來輸送電(dian)(dian)(dian)(dian)能，是(shi)(shi)電(dian)(dian)(dian)(dian)力(li)電(dian)(dian)(dian)(dian)纜的(de)(de)主要部分(fen)。絕緣(yuan)層絕緣(yuan)層是(shi)(shi)將線(xian)芯與大地(di)以及不(bu)同相的(de)(de)線(xian)芯間在電(dian)(dian)(dian)(dian)氣上彼此隔離，保證電(dian)(dian)(dian)(dian)能輸送，是(shi)(shi)電(dian)(dian)(dian)(dian)力(li)電(dian)(dian)(dian)(dian)纜結(jie)構中不(bu)可缺少的(de)(de)組成部分(fen)。屏(ping)蔽