地下(xia)電(dian)力電(dian)纜(lan)故障(zhang)復雜多變，引起電(dian)力電(dian)纜(lan)故障(zhang)的原因分類大致可歸納為以下(xia)幾(ji)類。

　　1.機械損傷

　　由機械損(sun)(sun)(sun)(sun)傷(shang)(shang)(shang)(shang)引(yin)起的(de)(de)(de)(de)電(dian)(dian)纜(lan)(lan)(lan)故(gu)障占電(dian)(dian)纜(lan)(lan)(lan)事(shi)故(gu)很(hen)大的(de)(de)(de)(de)比例。有些(xie)機械損(sun)(sun)(sun)(sun)傷(shang)(shang)(shang)(shang)很(hen)輕微，當時(shi)(shi)并未(wei)造(zao)成(cheng)故(gu)障，要(yao)在(zai)數(shu)月甚至數(shu)年(nian)后損(sun)(sun)(sun)(sun)傷(shang)(shang)(shang)(shang)才發(fa)展成(cheng)故(gu)障。造(zao)成(cheng)電(dian)(dian)纜(lan)(lan)(lan)的(de)(de)(de)(de)機械損(sun)(sun)(sun)(sun)傷(shang)(shang)(shang)(shang)的(de)(de)(de)(de)主要(yao)原因有：(1)安裝時(shi)(shi)損(sun)(sun)(sun)(sun)傷(shang)(shang)(shang)(shang)。安裝時(shi)(shi)不小心(xin)碰傷(shang)(shang)(shang)(shang)電(dian)(dian)纜(lan)(lan)(lan);機械牽引(yin)力(li)(li)過(guo)大拉(la)(la)傷(shang)(shang)(shang)(shang)電(dian)(dian)纜(lan)(lan)(lan);過(guo)度彎(wan)曲折(zhe)傷(shang)(shang)(shang)(shang)電(dian)(dian)纜(lan)(lan)(lan)。(2)直接(jie)受(shou)外力(li)(li)損(sun)(sun)(sun)(sun)傷(shang)(shang)(shang)(shang)。在(zai)安裝后的(de)(de)(de)(de)電(dian)(dian)纜(lan)(lan)(lan)路徑上(shang)或(huo)附近進行土建施工，使電(dian)(dian)纜(lan)(lan)(lan)直接(jie)受(shou)外力(li)(li)損(sun)(sun)(sun)(sun)傷(shang)(shang)(shang)(shang)。(3)行駛(shi)車輛的(de)(de)(de)(de)震動或(huo)沖擊(ji)性負荷也會(hui)造(zao)成(cheng)地(di)下電(dian)(dian)纜(lan)(lan)(lan)的(de)(de)(de)(de)鉛(qian)(鋁)包裂(lie)損(sun)(sun)(sun)(sun)。(4)因自然(ran)現象造(zao)成(cheng)的(de)(de)(de)(de)損(sun)(sun)(sun)(sun)傷(shang)(shang)(shang)(shang)。如中間(jian)接(jie)頭或(huo)終端(duan)頭的(de)(de)(de)(de)內絕緣膠(jiao)膨脹而脹裂(lie)外殼或(huo)電(dian)(dian)纜(lan)(lan)(lan)護(hu)套;裝在(zai)管口或(huo)支架(jia)上(shang)的(de)(de)(de)(de)電(dian)(dian)纜(lan)(lan)(lan)外皮擦(ca)傷(shang)(shang)(shang)(shang);因土地(di)沉(chen)降(jiang)引(yin)起過(guo)大拉(la)(la)力(li)(li)，拉(la)(la)斷(duan)中間(jian)接(jie)頭或(huo)導體。

　　電力電纜使用過程發生故障的原因分類

　　2.絕緣受潮

　　絕緣(yuan)受潮(chao)后會引起電纜耐壓下降而產生故障。電纜受潮(chao)的主(zhu)要原因有：(1)因接(jie)頭盒(he)(he)或(huo)終(zhong)端盒(he)(he)結構不密封或(huo)安裝不良而導致進水。(2)電纜制造不良，金(jin)屬護(hu)套有小孔或(huo)裂(lie)縫。(3)金(jin)屬護(hu)套因被外物(wu)刺傷或(huo)腐蝕(shi)穿孔。

　　3.絕緣(yuan)老化變質

　　絕緣(yuan)(yuan)老(lao)化會引起電(dian)纜(lan)(lan)耐壓(ya)下降而產生故障。電(dian)纜(lan)(lan)老(lao)化的(de)(de)主(zhu)要原因有：(1)電(dian)纜(lan)(lan)介(jie)質(zhi)內部(bu)的(de)(de)渣質(zhi)或(huo)(huo)氣隙，在(zai)電(dian)場(chang)作用(yong)(yong)下產生游(you)離和水解。(2)電(dian)纜(lan)(lan)過負荷或(huo)(huo)電(dian)纜(lan)(lan)溝通風不良，造成局部(bu)過熱。(3)油(you)浸紙絕緣(yuan)(yuan)電(dian)纜(lan)(lan)的(de)(de)絕緣(yuan)(yuan)物流失。(4)電(dian)力電(dian)纜(lan)(lan)超時限使用(yong)(yong)。

　　4.過(guo)電(dian)(dian)(dian)壓過(guo)電(dian)(dian)(dian)壓會使有缺陷(xian)的電(dian)(dian)(dian)纜絕緣層(ceng)發生(sheng)電(dian)(dian)(dian)擊穿，引起電(dian)(dian)(dian)纜故障。其主要(yao)原因(yin)有：大氣過(guo)電(dian)(dian)(dian)壓(如(ru)雷(lei)擊);內(nei)部(bu)過(guo)電(dian)(dian)(dian)壓(如(ru)操作過(guo)電(dian)(dian)(dian)壓)。

　　5.設(she)計(ji)(ji)和制(zhi)作(zuo)工(gong)藝(yi)不(bu)(bu)良電(dian)纜頭(tou)與中間設(she)計(ji)(ji)和制(zhi)作(zuo)工(gong)藝(yi)不(bu)(bu)良，也會(hui)引起(qi)電(dian)纜故障。其主要(yao)原(yuan)因為：電(dian)場分布設(she)計(ji)(ji)不(bu)(bu)周密;材料選用不(bu)(bu)當;工(gong)藝(yi)不(bu)(bu)良，不(bu)(bu)按(an)規程要(yao)求(qiu)制(zhi)作(zuo)。

　　電力電纜使用過程發生故障的原因分類

　　1.以故障材(cai)料(liao)特征分類

　　可分為串聯故(gu)(gu)(gu)(gu)(gu)障(zhang)(zhang)(zhang)、并(bing)聯故(gu)(gu)(gu)(gu)(gu)障(zhang)(zhang)(zhang)及復合故(gu)(gu)(gu)(gu)(gu)障(zhang)(zhang)(zhang)三類(lei)。(1)串聯故(gu)(gu)(gu)(gu)(gu)障(zhang)(zhang)(zhang)串聯故(gu)(gu)(gu)(gu)(gu)障(zhang)(zhang)(zhang)(金(jin)屬(shu)材(cai)料缺(que)陷(xian))是(shi)指電(dian)纜(lan)(lan)一(yi)(yi)個或(huo)(huo)多個導(dao)(dao)體(包(bao)括(kuo)鉛、鋁外(wai)(wai)皮(pi)(pi))斷(duan)(duan)開的(de)(de)故(gu)(gu)(gu)(gu)(gu)障(zhang)(zhang)(zhang)。它是(shi)廣義的(de)(de)電(dian)纜(lan)(lan)開路故(gu)(gu)(gu)(gu)(gu)障(zhang)(zhang)(zhang)。因纜(lan)(lan)芯(xin)的(de)(de)連續性(xing)受到破壞，形(xing)成斷(duan)(duan)線(xian)(xian)或(huo)(huo)不(bu)完全斷(duan)(duan)線(xian)(xian)。不(bu)完全斷(duan)(duan)線(xian)(xian)尤其不(bu)容易發現(xian)。串聯故(gu)(gu)(gu)(gu)(gu)障(zhang)(zhang)(zhang)具(ju)(ju)體可分為：一(yi)(yi)點開斷(duan)(duan)、多點開斷(duan)(duan)、一(yi)(yi)相(xiang)(xiang)斷(duan)(duan)線(xian)(xian)、多相(xiang)(xiang)斷(duan)(duan)線(xian)(xian)等。(2)并(bing)聯故(gu)(gu)(gu)(gu)(gu)障(zhang)(zhang)(zhang)并(bing)聯故(gu)(gu)(gu)(gu)(gu)障(zhang)(zhang)(zhang)(絕緣(yuan)材(cai)料缺(que)陷(xian))是(shi)指導(dao)(dao)體對(dui)外(wai)(wai)皮(pi)(pi)或(huo)(huo)導(dao)(dao)體之間(jian)的(de)(de)絕緣(yuan)水平(ping)下降，不(bu)能承受正常運行電(dian)壓而(er)發生的(de)(de)短(duan)路故(gu)(gu)(gu)(gu)(gu)障(zhang)(zhang)(zhang)。它是(shi)廣義的(de)(de)電(dian)纜(lan)(lan)短(duan)路故(gu)(gu)(gu)(gu)(gu)障(zhang)(zhang)(zhang)。這(zhe)類(lei)故(gu)(gu)(gu)(gu)(gu)障(zhang)(zhang)(zhang)由于纜(lan)(lan)芯(xin)之間(jian)或(huo)(huo)纜(lan)(lan)芯(xin)對(dui)外(wai)(wai)皮(pi)(pi)間(jian)的(de)(de)絕緣(yuan)破壞而(er)形(xing)成短(duan)路、接地、閃絡擊穿等現(xian)象，在現(xian)場出現(xian)頻率較高。并(bing)聯故(gu)(gu)(gu)(gu)(gu)障(zhang)(zhang)(zhang)具(ju)(ju)體可分為：一(yi)(yi)相(xiang)(xiang)接地、兩(liang)(liang)相(xiang)(xiang)接地、兩(liang)(liang)相(xiang)(xiang)短(duan)路、三相(xiang)(xiang)短(duan)路等。(3)復合故(gu)(gu)(gu)(gu)(gu)障(zhang)(zhang)(zhang)復合故(gu)(gu)(gu)(gu)(gu)障(zhang)(zhang)(zhang)(絕緣(yuan)材(cai)料、金(jin)屬(shu)材(cai)料都出現(xian)了(le)缺(que)陷(xian))是(shi)指纜(lan)(lan)芯(xin)與(yu)纜(lan)(lan)芯(xin)之間(jian)的(de)(de)絕緣(yuan)均出現(xian)故(gu)(gu)(gu)(gu)(gu)障(zhang)(zhang)(zhang)。它包(bao)括(kuo)一(yi)(yi)相(xiang)(xiang)斷(duan)(duan)線(xian)(xian)并(bing)接地、兩(liang)(liang)相(xiang)(xiang)斷(duan)(duan)線(xian)(xian)并(bing)接地、兩(liang)(liang)相(xiang)(xiang)短(duan)路并(bing)接地等。

　　2.以故障點(dian)絕緣特征(zheng)分類

　　根據(ju)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)纜(lan)(lan)(lan)(lan)故(gu)(gu)(gu)(gu)(gu)(gu)障(zhang)(zhang)(zhang)點絕(jue)緣(yuan)(yuan)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)阻(zu)Rf與擊(ji)(ji)穿(chuan)間(jian)隙G的(de)(de)(de)(de)情況(kuang)，電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)纜(lan)(lan)(lan)(lan)故(gu)(gu)(gu)(gu)(gu)(gu)障(zhang)(zhang)(zhang)又(you)可分(fen)(fen)為(wei)開(kai)路故(gu)(gu)(gu)(gu)(gu)(gu)障(zhang)(zhang)(zhang)、低(di)(di)阻(zu)故(gu)(gu)(gu)(gu)(gu)(gu)障(zhang)(zhang)(zhang)、高(gao)(gao)(gao)(gao)(gao)阻(zu)故(gu)(gu)(gu)(gu)(gu)(gu)障(zhang)(zhang)(zhang)、閃(shan)(shan)絡故(gu)(gu)(gu)(gu)(gu)(gu)障(zhang)(zhang)(zhang)四大類(lei)。該分(fen)(fen)類(lei)法為(wei)現(xian)(xian)(xian)(xian)(xian)(xian)(xian)(xian)(xian)場(chang)(chang)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)纜(lan)(lan)(lan)(lan)故(gu)(gu)(gu)(gu)(gu)(gu)障(zhang)(zhang)(zhang)*基本(ben)的(de)(de)(de)(de)分(fen)(fen)類(lei)方法，特(te)(te)別有利于(yu)(yu)(yu)探測(ce)方法的(de)(de)(de)(de)選擇(ze)。其(qi)(qi)(qi)中，間(jian)隙擊(ji)(ji)穿(chuan)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)壓(ya)UG的(de)(de)(de)(de)大小(xiao)取決(jue)(jue)于(yu)(yu)(yu)故(gu)(gu)(gu)(gu)(gu)(gu)障(zhang)(zhang)(zhang)點放電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)通道(即(ji)擊(ji)(ji)穿(chuan)間(jian)隙)的(de)(de)(de)(de)距離G，絕(jue)緣(yuan)(yuan)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)阻(zu)Rf的(de)(de)(de)(de)大小(xiao)取決(jue)(jue)于(yu)(yu)(yu)故(gu)(gu)(gu)(gu)(gu)(gu)障(zhang)(zhang)(zhang)點電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)纜(lan)(lan)(lan)(lan)介(jie)質碳化程度，分(fen)(fen)布電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)容Cf的(de)(de)(de)(de)大小(xiao)取決(jue)(jue)于(yu)(yu)(yu)故(gu)(gu)(gu)(gu)(gu)(gu)障(zhang)(zhang)(zhang)點受(shou)(shou)潮程度。(1)開(kai)路故(gu)(gu)(gu)(gu)(gu)(gu)障(zhang)(zhang)(zhang)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)纜(lan)(lan)(lan)(lan)金(jin)屬部分(fen)(fen)的(de)(de)(de)(de)連續性受(shou)(shou)到(dao)破壞(huai)，形成斷線(xian)，且故(gu)(gu)(gu)(gu)(gu)(gu)障(zhang)(zhang)(zhang)點的(de)(de)(de)(de)絕(jue)緣(yuan)(yuan)材料(liao)也受(shou)(shou)到(dao)不同程度的(de)(de)(de)(de)破壞(huai)。現(xian)(xian)(xian)(xian)(xian)(xian)(xian)(xian)(xian)場(chang)(chang)用(yong)(yong)兆(zhao)歐表(biao)測(ce)其(qi)(qi)(qi)絕(jue)緣(yuan)(yuan)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)阻(zu)Rf為(wei)無(wu)窮(qiong)大(∞)，但在(zai)直(zhi)流(liu)耐壓(ya)試(shi)驗時(shi)(shi)，會(hui)(hui)出(chu)現(xian)(xian)(xian)(xian)(xian)(xian)(xian)(xian)(xian)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)擊(ji)(ji)穿(chuan);檢查芯線(xian)導通情況(kuang)，有斷點。現(xian)(xian)(xian)(xian)(xian)(xian)(xian)(xian)(xian)場(chang)(chang)一(yi)(yi)般以一(yi)(yi)相或(huo)二相斷線(xian)并接(jie)地的(de)(de)(de)(de)形式(shi)出(chu)現(xian)(xian)(xian)(xian)(xian)(xian)(xian)(xian)(xian)。(2)低(di)(di)阻(zu)故(gu)(gu)(gu)(gu)(gu)(gu)障(zhang)(zhang)(zhang)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)纜(lan)(lan)(lan)(lan)絕(jue)緣(yuan)(yuan)材料(liao)受(shou)(shou)到(dao)損傷(shang)，出(chu)現(xian)(xian)(xian)(xian)(xian)(xian)(xian)(xian)(xian)接(jie)地故(gu)(gu)(gu)(gu)(gu)(gu)障(zhang)(zhang)(zhang)。現(xian)(xian)(xian)(xian)(xian)(xian)(xian)(xian)(xian)場(chang)(chang)用(yong)(yong)兆(zhao)歐表(biao)測(ce)其(qi)(qi)(qi)絕(jue)緣(yuan)(yuan)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)阻(zu)Rf小(xiao)于(yu)(yu)(yu)10Z0(Z0為(wei)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)纜(lan)(lan)(lan)(lan)的(de)(de)(de)(de)波阻(zu)抗，一(yi)(yi)般取10～40Ω之(zhi)間(jian))。現(xian)(xian)(xian)(xian)(xian)(xian)(xian)(xian)(xian)場(chang)(chang)一(yi)(yi)般低(di)(di)壓(ya)動(dong)力電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)纜(lan)(lan)(lan)(lan)和(he)控制(zhi)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)纜(lan)(lan)(lan)(lan)出(chu)現(xian)(xian)(xian)(xian)(xian)(xian)(xian)(xian)(xian)低(di)(di)阻(zu)故(gu)(gu)(gu)(gu)(gu)(gu)障(zhang)(zhang)(zhang)的(de)(de)(de)(de)幾率(lv)較高(gao)(gao)(gao)(gao)(gao)。(3)高(gao)(gao)(gao)(gao)(gao)阻(zu)故(gu)(gu)(gu)(gu)(gu)(gu)障(zhang)(zhang)(zhang)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)纜(lan)(lan)(lan)(lan)絕(jue)緣(yuan)(yuan)材料(liao)受(shou)(shou)到(dao)損傷(shang)，出(chu)現(xian)(xian)(xian)(xian)(xian)(xian)(xian)(xian)(xian)接(jie)地故(gu)(gu)(gu)(gu)(gu)(gu)障(zhang)(zhang)(zhang)。現(xian)(xian)(xian)(xian)(xian)(xian)(xian)(xian)(xian)場(chang)(chang)用(yong)(yong)兆(zhao)歐表(biao)測(ce)其(qi)(qi)(qi)絕(jue)緣(yuan)(yuan)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)阻(zu)Rf大于(yu)(yu)(yu)10Z0，在(zai)直(zhi)流(liu)高(gao)(gao)(gao)(gao)(gao)壓(ya)脈沖(chong)試(shi)驗時(shi)(shi)，會(hui)(hui)出(chu)現(xian)(xian)(xian)(xian)(xian)(xian)(xian)(xian)(xian)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)擊(ji)(ji)穿(chuan)。高(gao)(gao)(gao)(gao)(gao)阻(zu)故(gu)(gu)(gu)(gu)(gu)(gu)障(zhang)(zhang)(zhang)是高(gao)(gao)(gao)(gao)(gao)壓(ya)動(dong)力電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)纜(lan)(lan)(lan)(lan)(6KV或(huo)10KV電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)力電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)纜(lan)(lan)(lan)(lan))出(chu)現(xian)(xian)(xian)(xian)(xian)(xian)(xian)(xian)(xian)幾率(lv)*高(gao)(gao)(gao)(gao)(gao)的(de)(de)(de)(de)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)纜(lan)(lan)(lan)(lan)故(gu)(gu)(gu)(gu)(gu)(gu)障(zhang)(zhang)(zhang)，可達總(zong)故(gu)(gu)(gu)(gu)(gu)(gu)障(zhang)(zhang)(zhang)的(de)(de)(de)(de)80%以上。現(xian)(xian)(xian)(xian)(xian)(xian)(xian)(xian)(xian)場(chang)(chang)實測(ce)時(shi)(shi)，筆(bi)者一(yi)(yi)般取Rf=3KΩ為(wei)劃分(fen)(fen)高(gao)(gao)(gao)(gao)(gao)阻(zu)與低(di)(di)阻(zu)故(gu)(gu)(gu)(gu)(gu)(gu)障(zhang)(zhang)(zhang)的(de)(de)(de)(de)界線(xian)。因為(wei)Rf=3KΩ時(shi)(shi)，恰(qia)好能得(de)到(dao)回線(xian)法電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)橋精確測(ce)量所必需的(de)(de)(de)(de)10～50mA的(de)(de)(de)(de)測(ce)量電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)流(liu)。(4)閃(shan)(shan)絡故(gu)(gu)(gu)(gu)(gu)(gu)障(zhang)(zhang)(zhang)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)纜(lan)(lan)(lan)(lan)絕(jue)緣(yuan)(yuan)材料(liao)受(shou)(shou)到(dao)損傷(shang)，出(chu)現(xian)(xian)(xian)(xian)(xian)(xian)(xian)(xian)(xian)閃(shan)(shan)絡故(gu)(gu)(gu)(gu)(gu)(gu)障(zhang)(zhang)(zhang)。現(xian)(xian)(xian)(xian)(xian)(xian)(xian)(xian)(xian)場(chang)(chang)用(yong)(yong)兆(zhao)歐表(biao)測(ce)其(qi)(qi)(qi)絕(jue)緣(yuan)(yuan)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)阻(zu)Rf為(wei)無(wu)窮(qiong)大(∞)，但在(zai)直(zhi)流(liu)耐壓(ya)或(huo)高(gao)(gao)(gao)(gao)(gao)壓(ya)脈沖(chong)試(shi)驗時(shi)(shi)，會(hui)(hui)出(chu)現(xian)(xian)(xian)(xian)(xian)(xian)(xian)(xian)(xian)閃(shan)(shan)絡性電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)擊(ji)(ji)穿(chuan)。閃(shan)(shan)絡性故(gu)(gu)(gu)(gu)(gu)(gu)障(zhang)(zhang)(zhang)比較難測(ce)，特(te)(te)別是新敷設(she)的(de)(de)(de)(de)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)纜(lan)(lan)(lan)(lan)進(jin)行預防性試(shi)驗出(chu)現(xian)(xian)(xian)(xian)(xian)(xian)(xian)(xian)(xian)閃(shan)(shan)絡故(gu)(gu)(gu)(gu)(gu)(gu)障(zhang)(zhang)(zhang)時(shi)(shi)。現(xian)(xian)(xian)(xian)(xian)(xian)(xian)(xian)(xian)場(chang)(chang)一(yi)(yi)般使用(yong)(yong)直(zhi)流(liu)閃(shan)(shan)絡法進(jin)行探測(ce)。

　　電力電纜使用過程發生故障的原因分類

　　3.以(yi)故(gu)障觸(chu)發原(yuan)因及故(gu)障點特征分類

　　根據電力電纜(lan)在運行(xing)或預(yu)防性試驗中(zhong)，電纜(lan)、電纜(lan)頭及(ji)中(zhong)間(jian)盒出現不同特點(dian)的絕緣破壞(huai)，還可分為放(fang)炮故(gu)(gu)(gu)障(zhang)、擊穿故(gu)(gu)(gu)障(zhang)和運行(xing)故(gu)(gu)(gu)障(zhang)三類。

　　(1)放炮(pao)故(gu)障(zhang)在工(gong)礦企業，運(yun)行中的(de)電(dian)(dian)(dian)(dian)力(li)電(dian)(dian)(dian)(dian)纜(lan)，由于種種原因，絕緣出現(xian)嚴重損壞，產生(sheng)跳(tiao)閘的(de)事故(gu)。稱為電(dian)(dian)(dian)(dian)纜(lan)放炮(pao)。這類故(gu)障(zhang)的(de)特點是：電(dian)(dian)(dian)(dian)纜(lan)故(gu)障(zhang)點多數有鉛包(bao)或(huo)銅皮破裂，外部有不同程度的(de)變形(xing);電(dian)(dian)(dian)(dian)纜(lan)故(gu)障(zhang)性質常表(biao)現(xian)為兩相(xiang)短(duan)路接(jie)(jie)地(di)(di)或(huo)兩相(xiang)斷線(xian)(xian)并(bing)接(jie)(jie)地(di)(di)，其(qi)接(jie)(jie)地(di)(di)電(dian)(dian)(dian)(dian)阻(zu)一(yi)般較小(xiao)，解剖(pou)故(gu)障(zhang)點，可發現(xian)電(dian)(dian)(dian)(dian)弧擊穿的(de)碳化(hua)點或(huo)樹狀放電(dian)(dian)(dian)(dian)碳道(dao)與裂痕。電(dian)(dian)(dian)(dian)纜(lan)放炮(pao)故(gu)障(zhang)，其(qi)故(gu)障(zhang)特征明(ming)顯，大多數情況(kuang)下，運(yun)行值(zhi)班人員都能提供放炮(pao)大致位置。所以(yi)，這類故(gu)障(zhang)除少數較復雜(za)的(de)情況(kuang)需測(ce)距(ju)外，一(yi)般只(zhi)要用萬用表(biao)測(ce)定故(gu)障(zhang)的(de)具(ju)體性質(單(dan)相(xiang)接(jie)(jie)地(di)(di)、短(duan)路接(jie)(jie)地(di)(di)、斷線(xian)(xian)接(jie)(jie)地(di)(di)等)，可用聲測(ce)法直(zhi)接(jie)(jie)定點，簡單(dan)明(ming)了。

　　(2)擊穿故障

　　實際工作(zuo)中，因(yin)預防性試(shi)(shi)驗(yan)而觸發的(de)電(dian)(dian)(dian)纜絕緣破(po)壞(huai)事件，習(xi)慣稱為(wei)(wei)電(dian)(dian)(dian)纜擊(ji)穿(chuan)。該類故(gu)障(zhang)均發生在直流(liu)實驗(yan)電(dian)(dian)(dian)壓下，其絕緣破(po)壞(huai)為(wei)(wei)電(dian)(dian)(dian)擊(ji)穿(chuan)，接(jie)地(di)點一般鉛包或銅(tong)皮完(wan)好，外部無明顯變形(機械創傷除(chu)外)。電(dian)(dian)(dian)纜擊(ji)穿(chuan)故(gu)障(zhang)多(duo)為(wei)(wei)單純性接(jie)地(di)故(gu)障(zhang)，其接(jie)地(di)故(gu)障(zhang)較(jiao)高，解剖故(gu)障(zhang)點，絕緣材料沒有碳(tan)化點，但通過儀器可發現碳(tan)孔和(he)水樹(shu)枝老化結構。對(dui)電(dian)(dian)(dian)纜擊(ji)穿(chuan)故(gu)障(zhang)，特別是一些高阻接(jie)地(di)性電(dian)(dian)(dian)纜擊(ji)穿(chuan)故(gu)障(zhang)，其測(ce)(ce)試(shi)(shi)難點在測(ce)(ce)距。由(you)于(yu)該類故(gu)障(zhang)較(jiao)為(wei)(wei)隱蔽，測(ce)(ce)試(shi)(shi)參(can)數復雜多(duo)變，缺少規律性，所(suo)以能(neng)否迅速發現電(dian)(dian)(dian)纜故(gu)障(zhang)點，測(ce)(ce)距是關鍵。"高壓回線法"、"電(dian)(dian)(dian)錘(chui)法"均具有探測(ce)(ce)該類故(gu)障(zhang)*有效的(de)方法。

　　(3)運行故障

　　它是(shi)指工廠電(dian)(dian)(dian)(dian)力(li)系(xi)統在運(yun)(yun)行(xing)(xing)中，電(dian)(dian)(dian)(dian)纜(lan)(lan)(lan)饋出(chu)線、電(dian)(dian)(dian)(dian)機(ji)、變壓(ya)(ya)器的(de)(de)(de)(de)電(dian)(dian)(dian)(dian)纜(lan)(lan)(lan)引(yin)線，其高壓(ya)(ya)二次回路(lu)出(chu)現(xian)(xian)(xian)電(dian)(dian)(dian)(dian)壓(ya)(ya)波(bo)動(dong)或發現(xian)(xian)(xian)接(jie)(jie)(jie)(jie)地(di)(di)信號(hao)(有(you)接(jie)(jie)(jie)(jie)地(di)(di)保護(hu)(hu)的(de)(de)(de)(de)電(dian)(dian)(dian)(dian)力(li)元件(jian)出(chu)現(xian)(xian)(xian)接(jie)(jie)(jie)(jie)地(di)(di)跳(tiao)閘)，排除其他電(dian)(dian)(dian)(dian)力(li)元件(jian)故(gu)(gu)(gu)(gu)障(zhang)(zhang)的(de)(de)(de)(de)可能性而(er)確定的(de)(de)(de)(de)電(dian)(dian)(dian)(dian)纜(lan)(lan)(lan)故(gu)(gu)(gu)(gu)障(zhang)(zhang)。這類故(gu)(gu)(gu)(gu)障(zhang)(zhang)的(de)(de)(de)(de)*大特點就(jiu)是(shi)不明確。電(dian)(dian)(dian)(dian)纜(lan)(lan)(lan)運(yun)(yun)行(xing)(xing)故(gu)(gu)(gu)(gu)障(zhang)(zhang)的(de)(de)(de)(de)極(ji)端形式就(jiu)是(shi)電(dian)(dian)(dian)(dian)纜(lan)(lan)(lan)放(fang)炮(如兩點接(jie)(jie)(jie)(jie)地(di)(di)引(yin)發的(de)(de)(de)(de)相(xiang)間(jian)短路(lu));另一(yi)部(bu)(bu)分(fen)運(yun)(yun)行(xing)(xing)故(gu)(gu)(gu)(gu)障(zhang)(zhang)在做(zuo)停(ting)點檢查時，由于耐壓(ya)(ya)通(tong)(tong)不過(guo)而(er)發展成(cheng)電(dian)(dian)(dian)(dian)纜(lan)(lan)(lan)擊(ji)穿(chuan)故(gu)(gu)(gu)(gu)障(zhang)(zhang)(如電(dian)(dian)(dian)(dian)纜(lan)(lan)(lan)老(lao)化(hua)(hua)、絕(jue)(jue)緣(yuan)缺陷等);還有(you)一(yi)部(bu)(bu)分(fen)電(dian)(dian)(dian)(dian)纜(lan)(lan)(lan)運(yun)(yun)行(xing)(xing)故(gu)(gu)(gu)(gu)障(zhang)(zhang)是(shi)由于電(dian)(dian)(dian)(dian)纜(lan)(lan)(lan)引(yin)出(chu)線安裝位置不當(如電(dian)(dian)(dian)(dian)纜(lan)(lan)(lan)相(xiang)間(jian)或對地(di)(di)距離(li)不夠(gou)、電(dian)(dian)(dian)(dian)纜(lan)(lan)(lan)頭(tou)臟污或電(dian)(dian)(dian)(dian)機(ji)基礎進水等)，這些故(gu)(gu)(gu)(gu)障(zhang)(zhang)主(zhu)要進行(xing)(xing)一(yi)些簡(jian)單處(chu)理即可;*不明確的(de)(de)(de)(de)是(shi)那些瞬時接(jie)(jie)(jie)(jie)地(di)(di)、產(chan)生(sheng)不穩定閃(shan)絡(luo)的(de)(de)(de)(de)電(dian)(dian)(dian)(dian)纜(lan)(lan)(lan)運(yun)(yun)行(xing)(xing)故(gu)(gu)(gu)(gu)障(zhang)(zhang)。該類故(gu)(gu)(gu)(gu)障(zhang)(zhang)在電(dian)(dian)(dian)(dian)纜(lan)(lan)(lan)停(ting)電(dian)(dian)(dian)(dian)后(hou)，絕(jue)(jue)緣(yuan)電(dian)(dian)(dian)(dian)阻(zu)測量和直流耐壓(ya)(ya)實驗有(you)相(xiang)當部(bu)(bu)分(fen)可以(yi)通(tong)(tong)過(guo)，再把(ba)電(dian)(dian)(dian)(dian)纜(lan)(lan)(lan)投入(ru)(ru)系(xi)統后(hou)，也能正常(chang)運(yun)(yun)行(xing)(xing)一(yi)段時間(jian);剩(sheng)下的(de)(de)(de)(de)就(jiu)是(shi)單相(xiang)接(jie)(jie)(jie)(jie)地(di)(di)電(dian)(dian)(dian)(dian)纜(lan)(lan)(lan)故(gu)(gu)(gu)(gu)障(zhang)(zhang)，它們約占(zhan)電(dian)(dian)(dian)(dian)纜(lan)(lan)(lan)運(yun)(yun)行(xing)(xing)故(gu)(gu)(gu)(gu)障(zhang)(zhang)的(de)(de)(de)(de)40%，這種接(jie)(jie)(jie)(jie)地(di)(di)故(gu)(gu)(gu)(gu)障(zhang)(zhang)一(yi)般(ban)外(wai)部(bu)(bu)也沒有(you)明顯變形，接(jie)(jie)(jie)(jie)地(di)(di)電(dian)(dian)(dian)(dian)阻(zu)也不太高(一(yi)般(ban)幾十至幾百歐)。解剖故(gu)(gu)(gu)(gu)障(zhang)(zhang)點有(you)細(xi)微的(de)(de)(de)(de)碳化(hua)(hua)點。電(dian)(dian)(dian)(dian)纜(lan)(lan)(lan)運(yun)(yun)行(xing)(xing)接(jie)(jie)(jie)(jie)地(di)(di)故(gu)(gu)(gu)(gu)障(zhang)(zhang)原因有(you)兩種：其一(yi)，由于電(dian)(dian)(dian)(dian)纜(lan)(lan)(lan)運(yun)(yun)行(xing)(xing)時間(jian)較長，絕(jue)(jue)緣(yuan)層出(chu)現(xian)(xian)(xian)自(zi)然老(lao)化(hua)(hua);其二，電(dian)(dian)(dian)(dian)纜(lan)(lan)(lan)在腐蝕環境中，電(dian)(dian)(dian)(dian)纜(lan)(lan)(lan)護(hu)(hu)套被(bei)迅速破壞，腐蝕性氣體侵入(ru)(ru)絕(jue)(jue)緣(yuan)層使其劣化(hua)(hua)。電(dian)(dian)(dian)(dian)纜(lan)(lan)(lan)絕(jue)(jue)緣(yuan)層不管出(chu)現(xian)(xian)(xian)老(lao)化(hua)(hua)還是(shi)劣化(hua)(hua)，其擊(ji)穿(chuan)電(dian)(dian)(dian)(dian)壓(ya)(ya)都會下降，*終導致額定工頻(pin)電(dian)(dian)(dian)(dian)壓(ya)(ya)下的(de)(de)(de)(de)電(dian)(dian)(dian)(dian)擊(ji)穿(chuan)，從而(er)產(chan)生(sheng)電(dian)(dian)(dian)(dian)纜(lan)(lan)(lan)接(jie)(jie)(jie)(jie)地(di)(di)故(gu)(gu)(gu)(gu)障(zhang)(zhang)。這類故(gu)(gu)(gu)(gu)障(zhang)(zhang)可用"低(di)壓(ya)(ya)回線法"探測;用"電(dian)(dian)(dian)(dian)錘法"探測，效果也較好。