文(wen)章來源:國家電網(wang)公(gong)司 發布時(shi)間:2009-11-07
11月2日,由湖(hu)南省電力公司(si)試驗(yan)研(yan)究院研(yan)制的世界(jie)上首臺可調(diao)電容(rong)串聯補償式交流(liu)融冰(bing)(bing)裝置(zhi),在220千伏集里(li)變電站(zhan)一次(ci)試驗(yan)成功(gong)。這(zhe)種(zhong)裝置(zhi)是該(gai)院繼(ji)9月份(fen)自行(xing)研(yan)制成功(gong)國內首臺移動(dong)式短(duan)線路直(zhi)流(liu)融冰(bing)(bing)裝置(zhi)、移動(dong)式長線路直(zhi)流(liu)融冰(bing)(bing)裝置(zhi)后(hou)取得的又一重大突破。
本(ben)次試驗(yan)以集(ji)里變電(dian)站220千伏(fu)叢集(ji)線作為試驗(yan)對象,該裝置成(cheng)功地將(jiang)融(rong)冰(bing)(bing)電(dian)流升至810安。15分鐘后(hou),導線溫度(du)由17攝氏度(du)上升至35攝氏度(du),融(rong)冰(bing)(bing)裝置運(yun)行正常(chang)。
據(ju)了解,湖南(nan)(nan)(nan)公(gong)司(si)原有(you)的交流(liu)短路融冰(bing)技術有(you)較(jiao)大(da)的局限性,操作復雜,且必須保證線路阻(zu)抗匹配。在今年(nian)年(nian)初的冰(bing)雪災害(hai)中(zhong),湖南(nan)(nan)(nan)公(gong)司(si)共安(an)排(pai)交流(liu)融冰(bing)20條(tiao)(tiao)次(ci),平均每天只(zhi)能(neng)安(an)排(pai)1~2條(tiao)(tiao)線路融冰(bing)。而在覆冰(bing)情況較(jiao)為嚴重(zhong)的1月28日(ri),湖南(nan)(nan)(nan)覆冰(bing)超過3毫米的220千伏線路有(you)64條(tiao)(tiao),覆冰(bing)超過20毫米的有(you)40條(tiao)(tiao)。
可(ke)調電(dian)容(rong)串聯(lian)補償式交流融(rong)(rong)冰(bing)裝置的(de)成功問世,標(biao)志著(zhu)利(li)用10千伏電(dian)源即可(ke)實現單條不同長度輸(shu)電(dian)線路的(de)交流融(rong)(rong)冰(bing),大(da)大(da)延長了(le)融(rong)(rong)冰(bing)線路,減少了(le)線路融(rong)(rong)冰(bing)所需的(de)系統容(rong)量,同時避免(mian)了(le)傳統方式融(rong)(rong)冰(bing)所需的(de)線路阻(zu)抗匹配和繁雜的(de)系統倒(dao)閘操作,縮短了(le)融(rong)(rong)冰(bing)操作時間,提高(gao)了(le)融(rong)(rong)冰(bing)工(gong)作效率。據湖南(nan)公司(si)試研院相關(guan)人士介紹,在設備臺數可(ke)以保證的(de)情況(kuang)下,利(li)用可(ke)調電(dian)容(rong)串聯(lian)補償式交流融(rong)(rong)冰(bing)技術,一天可(ke)為上百條線路進行(xing)融(rong)(rong)冰(bing)作業。新(xin)技術對今年電(dian)網抗冰(bing)防災(zai)極(ji)其有用,為電(dian)網提供了(le)一種(zhong)更(geng)加安全、經濟(ji)、便捷(jie)的(de)融(rong)(rong)冰(bing)裝置。
相關鏈接
融冰裝置研發背景
今年(nian)年(nian)初的(de)冰雪災(zai)害是我國(guo)(guo)電(dian)(dian)(dian)(dian)網(wang)(wang)有史以(yi)來受災(zai)最嚴(yan)重(zhong)(zhong)的(de)一次。由于大范(fan)圍凍(dong)雨滴水成(cheng)冰,電(dian)(dian)(dian)(dian)網(wang)(wang)覆冰厚度嚴(yan)重(zhong)(zhong)超過(guo)我國(guo)(guo)現行的(de)設計(ji)(ji)標準(zhun),導(dao)致大面積倒塔(桿)斷(duan)線。國(guo)(guo)家電(dian)(dian)(dian)(dian)網(wang)(wang)累(lei)計(ji)(ji)停(ting)運35千伏(fu)(fu)及以(yi)上變電(dian)(dian)(dian)(dian)站(zhan)884座,停(ting)運10千伏(fu)(fu)及以(yi)上輸電(dian)(dian)(dian)(dian)線路1.53萬(wan)條(tiao)(tiao),損(sun)毀高壓桿塔18.4萬(wan)基(ji),倒斷(duan)低壓線桿51.9萬(wan)基(ji)。湖南(nan)電(dian)(dian)(dian)(dian)網(wang)(wang)一度瀕臨崩潰,郴州、衡陽(yang)等地區供電(dian)(dian)(dian)(dian)中(zhong)斷(duan)。江(jiang)西電(dian)(dian)(dian)(dian)網(wang)(wang)先后(hou)5次與華中(zhong)主網(wang)(wang)解列(lie),省網(wang)(wang)一度解列(lie)成(cheng)三片(pian)運行。浙江(jiang)多條(tiao)(tiao)500千伏(fu)(fu)線路停(ting)運。福建電(dian)(dian)(dian)(dian)網(wang)(wang)持(chi)續31天孤網(wang)(wang)運行。災(zai)后(hou)國(guo)(guo)家電(dian)(dian)(dian)(dian)網(wang)(wang)恢(hui)復重(zhong)(zhong)建和改造投入(ru)資金達390億元。
交流短路融冰
減少(shao)輸(shu)電(dian)(dian)線(xian)路(lu)(lu)(lu)冰(bing)(bing)(bing)害損(sun)失(shi)的(de)(de)主要(yao)途(tu)徑有(you)(you)(you)兩(liang)種(zhong)。一(yi)(yi)是加強輸(shu)電(dian)(dian)線(xian)路(lu)(lu)(lu)的(de)(de)抗冰(bing)(bing)(bing)能力。但(dan)每改造(zao)一(yi)(yi)基(ji)220千伏(fu)桿塔(ta)及導(dao)線(xian)需30萬~40萬元,一(yi)(yi)條(tiao)中(zhong)等長度(du)的(de)(de)220千伏(fu)輸(shu)電(dian)(dian)線(xian)路(lu)(lu)(lu)(桿塔(ta)120基(ji)),改造(zao)總費用(yong)(yong)3000萬~5000萬元。二是進行短(duan)路(lu)(lu)(lu)融(rong)冰(bing)(bing)(bing)。為有(you)(you)(you)效抗擊冰(bing)(bing)(bing)災(zai),從上世紀70年代(dai)起,湖南電(dian)(dian)網(wang)即(ji)研發出一(yi)(yi)套(tao)交流短(duan)路(lu)(lu)(lu)融(rong)冰(bing)(bing)(bing)技(ji)術(shu),并成功應(ying)用(yong)(yong)30多(duo)年。但(dan)這種(zhong)融(rong)冰(bing)(bing)(bing)技(ji)術(shu)有(you)(you)(you)諸多(duo)局(ju)限性(xing),在(zai)電(dian)(dian)網(wang)遭受大(da)范圍雨雪冰(bing)(bing)(bing)凍災(zai)害時往往束手無策,所以有(you)(you)(you)進一(yi)(yi)步改造(zao)的(de)(de)需要(yao)。
阻抗匹配是關鍵
阻抗(kang)匹配是指(zhi)給輸電線(xian)(xian)路(lu)融冰時(shi)的(de)電流(liu)不能過(guo)大或過(guo)小,因此線(xian)(xian)路(lu)長度必須在(zai)一(yi)個相(xiang)對固定的(de)范圍內。過(guo)大,導線(xian)(xian)就會燒毀,過(guo)小,發熱不夠,無法將(jiang)線(xian)(xian)路(lu)上的(de)冰融化。