擴徑(jing)導(dao)線(xian)(xian)(xian)(xian)是(shi)以滿足(zu)技(ji)(ji)術(shu)條件(jian)的(de)(de)常規導(dao)線(xian)(xian)(xian)(xian)規格為(wei)基準，采取擴大導(dao)線(xian)(xian)(xian)(xian)外徑(jing)技(ji)(ji)術(shu)，在保證(zheng)電暈所要求的(de)(de)導(dao)線(xian)(xian)(xian)(xian)外徑(jing)前提(ti)下，減少導(dao)線(xian)(xian)(xian)(xian)的(de)(de)鋁截面，從而(er)減少導(dao)線(xian)(xian)(xian)(xian)的(de)(de)總重量，減少鐵塔荷載和結構重量，極(ji)大地降(jiang)低線(xian)(xian)(xian)(xian)路造價。

交流輸電(dian)(dian)線(xian)(xian)(xian)(xian)路的電(dian)(dian)暈(yun)損失主(zhu)要(yao)(yao)與導(dao)(dao)(dao)(dao)線(xian)(xian)(xian)(xian)表(biao)面(mian)場(chang)(chang) 強和天氣有關，根(gen)據絕緣(yuan)水平要(yao)(yao)求確定了(le)(le)相(xiang)間距(ju)離后(hou)(hou)，導(dao)(dao)(dao)(dao)線(xian)(xian)(xian)(xian)表(biao)面(mian)場(chang)(chang)強主(zhu)要(yao)(yao)與導(dao)(dao)(dao)(dao)線(xian)(xian)(xian)(xian)分(fen)裂數(shu)、分(fen)裂間距(ju)和 子導(dao)(dao)(dao)(dao)線(xian)(xian)(xian)(xian)直徑(jing)(jing)有關，分(fen)裂數(shu)越多，子導(dao)(dao)(dao)(dao)線(xian)(xian)(xian)(xian)直徑(jing)(jing)越大(da)(da)， 表(biao)面(mian)場(chang)(chang)強越小(xiao)(xiao)。擴(kuo)(kuo)徑(jing)(jing)導(dao)(dao)(dao)(dao)線(xian)(xian)(xian)(xian)通過支撐(cheng)鋁(lv)線(xian)(xian)(xian)(xian)疏繞的方式 擴(kuo)(kuo)大(da)(da)了(le)(le)導(dao)(dao)(dao)(dao)線(xian)(xian)(xian)(xian)外(wai)徑(jing)(jing)，這樣可(ke)減小(xiao)(xiao)導(dao)(dao)(dao)(dao)線(xian)(xian)(xian)(xian)表(biao)面(mian)的電(dian)(dian)場(chang)(chang)強度(du)和電(dian)(dian)暈(yun)放電(dian)(dian)，降低噪聲，減少對無線(xian)(xian)(xian)(xian)電(dian)(dian)的干擾。相(xiang)對于常(chang)規導(dao)(dao)(dao)(dao)線(xian)(xian)(xian)(xian)，擴(kuo)(kuo)徑(jing)(jing)導(dao)(dao)(dao)(dao)線(xian)(xian)(xian)(xian)重量較(jiao)輕，安裝敷設后(hou)(hou)的 塑蠕(ru)伸(shen)長減小(xiao)(xiao)，導(dao)(dao)(dao)(dao)線(xian)(xian)(xian)(xian)永久變形減少，在滿(man)足輸送容 量要(yao)(yao)求和環境保護指(zhi)標的前提下，可(ke)大(da)(da)幅降低線(xian)(xian)(xian)(xian)路 整體造價。簡單說來，擴(kuo)(kuo)徑(jing)(jing)導(dao)(dao)(dao)(dao)線(xian)(xian)(xian)(xian)是(shi)從常(chang)規導(dao)(dao)(dao)(dao)線(xian)(xian)(xian)(xian)中抽取數(shu)股鋁(lv)線(xian)(xian)(xian)(xian)后(hou)(hou)繞制而成的。