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1. 原始的高壓防雷技術
電力裝置在其發展使用初期大都是通過裸導線架空線路輸電,架空導線一般在離地麵6~18m的(de)空(kong)間(jian),通(tong)過(guo)雷(lei)電(dian)入(ru)侵(qin)波(bo)產(chan)生(sheng)的(de)雷(lei)電(dian)過(guo)電(dian)壓(ya)使(shi)線(xian)路(lu)或(huo)設(she)備(bei)絕(jue)緣(yuan)擊(ji)穿(chuan)而(er)損(sun)壞(huai)。當(dang)時(shi)人(ren)們(men)通(tong)過(guo)在(zai)線(xian)路(lu)或(huo)設(she)備(bei)上(shang)人(ren)為(wei)地(di)製(zhi)造(zao)絕(jue)緣(yuan)薄(bo)弱(ruo)點(dian)即(ji)間(jian)隙(xi)裝(zhuang)置(zhi),間(jian)隙(xi)的(de)擊(ji)穿(chuan)電(dian)壓(ya)比(bi)線(xian)路(lu)或(huo)設(she)備(bei)的(de)雷(lei)電(dian)衝(chong)擊(ji)絕(jue)緣(yuan)水(shui)平(ping)低(di),在(zai)正(zheng)常(chang)運(yun)行(xing)電(dian)壓(ya)下(xia)間(jian)隙(xi)處(chu)於(yu)隔(ge)離(li)絕(jue)緣(yuan)狀(zhuang)態(tai),當(dang)雷(lei)電(dian)發(fa)生(sheng)時(shi)強(qiang)大(da)的(de)過(guo)電(dian)壓(ya)使(shi)間(jian)隙(xi)擊(ji)穿(chuan),從(cong)而(er)產(chan)生(sheng)接(jie)地(di)保(bao)護(hu),起(qi)到(dao)保(bao)護(hu)線(xian)路(lu)或(huo)設(she)備(bei)絕(jue)緣(yuan)的(de)作(zuo)用(yong)。
1.1 間隙保護技術:間(jian)隙(xi)保(bao)護(hu)就(jiu)是(shi)線(xian)路(lu)大(da)體(ti)的(de)兩(liang)極(ji)由(you)角(jiao)形(xing)棒(bang)組(zu)成(cheng),一(yi)極(ji)固(gu)定(ding)在(zai)絕(jue)緣(yuan)件(jian)上(shang)連(lian)接(jie)帶(dai)電(dian)導(dao)線(xian),而(er)另(ling)一(yi)極(ji)接(jie)地(di),間(jian)隙(xi)擊(ji)穿(chuan)後(hou)電(dian)弧(hu)在(zai)角(jiao)形(xing)棒(bang)間(jian)上(shang)升(sheng)拉(la)長(chang),當(dang)電(dian)弧(hu)電(dian)流(liu)變(bian)小(xiao)時(shi)可(ke)以(yi)自(zi)行(xing)熄(xi)弧(hu),間(jian)隙(xi)保(bao)護(hu)技(ji)術(shu)的(de)缺(que)點(dian)是(shi)當(dang)電(dian)弧(hu)電(dian)流(liu)大(da)到(dao)幾(ji)十(shi)安(an)以(yi)上(shang)時(shi)就(jiu)沒(mei)法(fa)自(zi)行(xing)熄(xi)弧(hu),雷(lei)電(dian)過(guo)電(dian)壓(ya)時(shi),單(dan)相(xiang)、兩相或三相間隙都可能擊穿接地,造成接地故障、兩相或三相間短路故障,以致線路電源斷路器保護動作分閘。
1.2 管型避雷器技術:guanxingbileiqijishushiliyongyizhongjuyoupenqixihugongnengdejianxizhuangzhi,cizhuangzhiyouneiwailianggejianxi,waijianxileisibaohujianxi,liangjijungudingzaijueyuanjianshang,neijianxizhiyubileiqiguannei,dangleidianguodianyaneiwaijianxijichuanshi,leidianliuhegongpinduanludianliujingguanneibijiedi,guanbiwuzhishoureqihua,youjiaodayaliqitijingneijianxipenchuguanwai,qiangzhijianxixihu。guanxingbileiqijishuyecunzaihenduodequedian:此裝置的的選用受安裝地點的限製,其次還受線路最大、最小短路電流的製約,最大短路電流大於避雷器的斷流上限時避雷器會爆炸;duanludianliuxiaoyubileiqideduanliuxiaxianshijiubunengxihu,bileiqikenengshaohuai。lingwaiguanxingbileiqiduocidongzuohou,guanneijinghuizhujianzengda,xihunenglihuixiajiangshenzhixiaoshi。
2. 新型防雷技術的應用
jianxibaohujishuheguanxingbileiqijishudoushikaojianxijichuanjiedifangdianjiangyalaiqidaobaohudezuoyong,yishangliangzhongfangleijishuwangwanghuizaochengjiediguzhanghuoxiangjianduanluguzhang,bunengdadaokexuehelidebaohuzuoyong。muqianzaidianlixitongzhongfangleibaohujinjiangtamenyongyushudianxianlufanglei,tongshiweilejinliangjianshaoxianlutingdianshigu,yuzidongzhonghezhazhuangzhipeiheshiyong。gengweikexuehelidefangleicuoshishifaxingbileiqijishu,shimuqiandianligaoyafangleizuiweipubiandedianqishebeifangleijishu。qiyuanlishizaiguodianyaxiazidongkaizhaxieliujiangya,huifuyunxingdianyashibizhaduanliu,zhezhongbaohuzuoyongshikaobileiqineidianzuyuanjiandexianliuxianyazuoyongshixiande,guodianyaxiadianzuyuanjiankejiangleidianliuxianzhizai5kA內,殘壓限製在設備的雷電衝擊絕緣水平以下;youxiedianzuyuanjianzaiyunxingdianyaxiarengyouxuliutongguo,changshijianxuliuhuishiguanxingbileiqisunhuai,guyibanxujiachuanlianjianxigeliyunxingdianya,bingkaojianximiehuheqieduanxuliu。faxingbileiqituchuyoudianshibileiqidedianzuyuanjiankebimiandianlixitongzhijiejiedihuoxiangjianduanluguzhang,qibaohuzuoyongbuhuiyingxiangdianlixitongdezhengchanganquanyunxing。
2.1 碳化矽避雷器技術:碳化矽避雷器結構為將間隙和若幹片SiC閥片壓緊密封在避雷器瓷套內,保護作用是利用SiC閥fa片pian的de非fei線xian性xing特te性xing,在zai過guo電dian壓ya下xia電dian阻zu變bian得de很hen小xiao,可ke大da量liang泄xie放fang雷lei電dian流liu限xian製zhi殘can壓ya,而er在zai雷lei電dian壓ya過guo去qu後hou電dian阻zu自zi動dong增zeng大da,限xian製zhi續xu流liu在zai幾ji十shi安an內nei,使shi間jian隙xi能neng滅mie弧hu和he斷duan流liu。碳tan化hua矽gui避bi雷lei器qi技ji術shu是shi現xian行xing防fang雷lei技ji術shu中zhong主zhu要yao的de防fang雷lei電dian器qi。
2.2 氧化鋅避雷器:氧化鋅避雷器簡稱MOA, 與傳統的碳化矽避雷器相比,MOA具有保護特性好,通流能力大,耐汙能力強,結構簡單,可靠性高等特點,能對輸變電設備提供最佳保護。
碳化矽避雷器技術在防雷性能上有其突出的優點被電力係統高壓設備廣泛采用,但也存在著一定的缺點:一是隻有雷電最大幅值限壓保護功能,而無雷電陡波保護功能,防雷保護功能不完全;二是沒有連續雷電衝擊保護能力;三是動作特性穩定性差可能遭受暫態過電壓危害;四si是shi動dong作zuo負fu載zai重zhong使shi用yong壽shou命ming短duan等deng。這zhe些xie潛qian在zai的de缺que點dian已yi暴bao露lu出chu碳tan化hua矽gui避bi雷lei器qi在zai使shi用yong的de過guo程cheng當dang中zhong存cun在zai影ying響xiang電dian力li安an全quan的de隱yin患huan性xing且qie其qi產chan品pin技ji術shu也ye比bi較jiao落luo後hou。氧yang化hua鋅xin避bi雷lei器qi按an外wai殼ke材cai料liao分fen為wei瓷ci套tao式shi、罐式、複合外套式三大類;按使用場所分配電、電站、線路、並聯補償電容器、變壓器和電機中性點、發(fa)電(dian)機(ji)和(he)電(dian)動(dong)機(ji)保(bao)護(hu)用(yong)六(liu)大(da)類(lei),氧(yang)化(hua)鋅(xin)避(bi)雷(lei)器(qi)技(ji)術(shu)在(zai)繼(ji)承(cheng)了(le)碳(tan)化(hua)矽(gui)避(bi)雷(lei)器(qi)技(ji)術(shu)的(de)基(ji)礎(chu)上(shang),無(wu)論(lun)是(shi)在(zai)設(she)計(ji)的(de)思(si)想(xiang)上(shang),還(hai)是(shi)在(zai)產(chan)品(pin)功(gong)能(neng)的(de)完(wan)善(shan)上(shang)都(dou)是(shi)世(shi)界(jie)公(gong)認(ren)的(de)當(dang)代(dai)最(zui)為(wei)先(xian)進(jin)防(fang)雷(lei)電(dian)器(qi)。氧(yang)化(hua)鋅(xin)避(bi)雷(lei)器(qi)的(de)結(jie)構(gou)為(wei)將(jiang)若(ruo)幹(gan)片(pian)ZnO閥片壓緊密封在避雷器瓷套內。ZnO閥(fa)片(pian)具(ju)有(you)非(fei)常(chang)優(you)異(yi)的(de)非(fei)線(xian)性(xing)特(te)性(xing),在(zai)較(jiao)高(gao)電(dian)壓(ya)下(xia)電(dian)阻(zu)很(hen)小(xiao),可(ke)以(yi)泄(xie)放(fang)大(da)量(liang)雷(lei)電(dian)流(liu),殘(can)壓(ya)很(hen)低(di),在(zai)電(dian)網(wang)運(yun)行(xing)電(dian)壓(ya)下(xia)電(dian)阻(zu)很(hen)大(da)很(hen)大(da),泄(xie)漏(lou)電(dian)流(liu)隻(zhi)有(you)50~150μA,dianliuhenxiaokeshiweiwugongpinxuliu,zhejiushizuochengwujianxiyanghuaxinbileiqideyuanyin,qituchuyoudianshitaduileidiandouboheleidianfuzhitongyangyouxianyazuoyong,fangleibaohugongnengwanquan。
我(wo)國(guo)最(zui)先(xian)生(sheng)產(chan)使(shi)用(yong)的(de)是(shi)無(wu)間(jian)隙(xi)氧(yang)化(hua)鋅(xin)避(bi)雷(lei)器(qi),經(jing)過(guo)長(chang)期(qi)的(de)運(yun)行(xing)實(shi)踐(jian),發(fa)現(xian)它(ta)有(you)損(sun)壞(huai)爆(bao)炸(zha)率(lv)高(gao),使(shi)用(yong)壽(shou)命(ming)短(duan)等(deng)缺(que)點(dian),原(yuan)因(yin)是(shi)暫(zan)態(tai)過(guo)電(dian)壓(ya)承(cheng)受(shou)能(neng)力(li)差(cha)是(shi)其(qi)致(zhi)命(ming)弱(ruo)點(dian)。而(er)串(chuan)聯(lian)間(jian)隙(xi)氧(yang)化(hua)鋅(xin)避(bi)雷(lei)器(qi)仍(reng)有(you)無(wu)間(jian)隙(xi)氧(yang)化(hua)鋅(xin)避(bi)雷(lei)器(qi)的(de)保(bao)護(hu)性(xing)能(neng)優(you)點(dian),同(tong)時(shi)有(you)暫(zan)態(tai)過(guo)電(dian)壓(ya)承(cheng)受(shou)能(neng)力(li)強(qiang)的(de)特(te)點(dian),是(shi)一(yi)種(zhong)理(li)想(xiang)地(di)揚(yang)長(chang)避(bi)短(duan)產(chan)品(pin),結(jie)合(he)國(guo)情(qing)在(zai)3~ 35kV係統串聯間隙氧化鋅避雷器才是當代最先進防雷電器。
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