電(dian)(dian)(dian)暈噪(zao)(zao)聲(sheng)(sheng)(sheng)(sheng)是(shi)(shi)指伴隨著導線周(zhou)圍的(de)(de)(de)電(dian)(dian)(dian)暈或火花(hua)放電(dian)(dian)(dian)所產生的(de)(de)(de)一種噪(zao)(zao)聲(sheng)(sheng)(sheng)(sheng)，屬于(yu)(yu)聲(sheng)(sheng)(sheng)(sheng)頻干擾(rao)。電(dian)(dian)(dian)暈噪(zao)(zao)聲(sheng)(sheng)(sheng)(sheng)頻率范圍一般為(wei)(wei)(wei)60～4000Hz，峰(feng)值(zhi)頻率是(shi)(shi)工頻的(de)(de)(de)2倍左右(you)。輸電(dian)(dian)(dian)線路(lu)(lu)可聽(ting)噪(zao)(zao)聲(sheng)(sheng)(sheng)(sheng)屬于(yu)(yu)低(di)頻范圍，具有(you)較強的(de)(de)(de)穿透(tou)力(li)，衰減(jian)較慢，能傳播(bo)到較遠(yuan)的(de)(de)(de)地方，一般可達(da)1km。我國以往輸電(dian)(dian)(dian)線路(lu)(lu)建成后(hou)出現過局部區(qu)域噪(zao)(zao)聲(sheng)(sheng)(sheng)(sheng)擾(rao)民，而現場測量噪(zao)(zao)聲(sheng)(sheng)(sheng)(sheng)并未超標的(de)(de)(de)現象，因(yin)此有(you)必要在人(ren)口(kou)密集的(de)(de)(de)地區(qu)將可聽(ting)噪(zao)(zao)聲(sheng)(sheng)(sheng)(sheng)限值(zhi)降(jiang)低(di)。例如某(mou)線路(lu)(lu)的(de)(de)(de)可聽(ting)噪(zao)(zao)聲(sheng)(sheng)(sheng)(sheng)限值(zhi)為(wei)(wei)(wei)55dB(A)，但是(shi)(shi)由于(yu)(yu)沿線的(de)(de)(de)人(ren)口(kou)較密集，若將線路(lu)(lu)的(de)(de)(de)電(dian)(dian)(dian)暈噪(zao)(zao)聲(sheng)(sheng)(sheng)(sheng)設(she)計為(wei)(wei)(wei)不超過53dB(A)，則對環境更(geng)為(wei)(wei)(wei)友(you)好。

當輸(shu)送(song)容量、電壓、分裂數(shu)、子導線(xian)(xian)間距等不變(bian)的情況(kuang)下，略(lve)微增大導線(xian)(xian)外徑即可降(jiang)低(di)電暈噪聲滿足周圍環(huan)境(jing)要(yao)求，那(nei)么在(zai)(zai)導線(xian)(xian)截(jie)面不變(bian)的情況(kuang)下使用(yong)擴(kuo)徑導線(xian)(xian)就是一(yi)種(zhong)在(zai)(zai)人口(kou)密(mi)集區降(jiang)低(di)輸(shu)電線(xian)(xian)路(lu)噪聲的有(you)效措施。因此，擴(kuo)徑導線(xian)(xian)是適(shi)用(yong)于我(wo)國(guo)人口(kou)密(mi)集的地區線(xian)(xian)路(lu)的一(yi)種(zhong)導線(xian)(xian)類型。

    隨著我國社(she)會經濟的發展(zhan)，將繼續建(jian)設交流(liu)特高壓工(gong)程(cheng)、西電東送等輸電線路工(gong)程(cheng)，線路經過(guo)人(ren)口密集的地區不可(ke)避免(mian)，因此擴(kuo)徑(jing)導(dao)線將有廣泛的應用(yong)前景，深入開展(zhan)擴(kuo)徑(jing)導(dao)線的研究具有重大意義。