一、環網柜是干什么的
環網柜是一組輸(shu)配電(dian)(dian)氣設(she)備(高(gao)(gao)壓開關設(she)備)裝在金屬或(huo)非金屬絕(jue)緣柜體內或(huo)做成拼裝間隔式環(huan)網供電(dian)(dian)單元(yuan)的(de)電(dian)(dian)氣設(she)備,其核(he)心部分(fen)采用負荷開關和(he)熔斷(duan)器,具有結構簡單、體積小、價格(ge)低(di)、可提高(gao)(gao)供電(dian)(dian)參(can)數和(he)性能以(yi)及(ji)供電(dian)(dian)安全等優點。它(ta)被廣泛(fan)使用于城(cheng)市住(zhu)宅小區、高(gao)(gao)層建(jian)筑、大型(xing)公共(gong)建(jian)筑、工廠企業等負荷中心的(de)配電(dian)(dian)站以(yi)及(ji)箱式變(bian)電(dian)(dian)站中。
二、環網柜的作用
環(huan)網柜的作用(yong)是(shi)聯(lian)系環(huan)網線路(lu),提高(gao)線路(lu)的供電可靠(kao)性(xing),還(huan)有(you)就是(shi)保(bao)護變(bian)壓(ya)(ya)器(qi)(qi)、限制短(duan)(duan)路(lu)電流(liu),使變(bian)壓(ya)(ya)器(qi)(qi)免于承受(shou)突發短(duan)(duan)路(lu)故(gu)障(zhang)(zhang)電流(liu),并在10msl以內快速切(qie)除變(bian)壓(ya)(ya)器(qi)(qi)內部短(duan)(duan)路(lu)故(gu)障(zhang)(zhang),防止有(you)內部電弧弓(gong)起(qi)的壓(ya)(ya)動升而導致變(bian)壓(ya)(ya)器(qi)(qi)損害,使變(bian)壓(ya)(ya)器(qi)(qi)得(de)到(dao)更為(wei)可靠(kao)合理(li)的保(bao)護。而對于變(bian)壓(ya)(ya)器(qi)(qi)低壓(ya)(ya)側(ce)端(duan)部短(duan)(duan)路(lu),合理(li)地選用(yong)高(gao)壓(ya)(ya)熔絲,由高(gao)壓(ya)(ya)側(ce)熔斷器(qi)(qi)切(qie)除低壓(ya)(ya)側(ce)端(duan)部短(duan)(duan)路(lu)故(gu)障(zhang)(zhang),有(you)效地保(bao)護變(bian)壓(ya)(ya)器(qi)(qi)。
三、環網柜的工作原理
環網是指(zhi)環形(xing)配(pei)電(dian)(dian)網,即(ji)供(gong)(gong)(gong)電(dian)(dian)干(gan)線(xian)(xian)形(xing)成一(yi)個(ge)閉合的(de)環形(xing),供(gong)(gong)(gong)電(dian)(dian)電(dian)(dian)源向(xiang)這個(ge)環形(xing)干(gan)線(xian)(xian)供(gong)(gong)(gong)電(dian)(dian),從(cong)(cong)干(gan)線(xian)(xian)上再(zai)一(yi)路(lu)一(yi)路(lu)地通過(guo)高壓開關向(xiang)外(wai)配(pei)電(dian)(dian)。這樣的(de)好處是,每一(yi)個(ge)配(pei)電(dian)(dian)支(zhi)(zhi)路(lu)既可(ke)以從(cong)(cong)它(ta)(ta)的(de)左(zuo)側(ce)(ce)(ce)干(gan)線(xian)(xian)取電(dian)(dian)源,又(you)可(ke)以從(cong)(cong)它(ta)(ta)右(you)側(ce)(ce)(ce)干(gan)線(xian)(xian)取電(dian)(dian)源。當(dang)左(zuo)側(ce)(ce)(ce)干(gan)線(xian)(xian)出(chu)了(le)故障,它(ta)(ta)就從(cong)(cong)右(you)側(ce)(ce)(ce)干(gan)線(xian)(xian)繼(ji)續得到供(gong)(gong)(gong)電(dian)(dian),而(er)當(dang)右(you)側(ce)(ce)(ce)干(gan)線(xian)(xian)出(chu)了(le)故障,它(ta)(ta)就從(cong)(cong)左(zuo)側(ce)(ce)(ce)干(gan)線(xian)(xian)繼(ji)續得到供(gong)(gong)(gong)電(dian)(dian),這樣一(yi)來,盡管(guan)總電(dian)(dian)源是單路(lu)供(gong)(gong)(gong)電(dian)(dian)的(de),但從(cong)(cong)每一(yi)個(ge)配(pei)電(dian)(dian)支(zhi)(zhi)路(lu)來說卻得到類似于(yu)雙(shuang)路(lu)供(gong)(gong)(gong)電(dian)(dian)的(de)實惠,從(cong)(cong)而(er)提(ti)高了(le)供(gong)(gong)(gong)電(dian)(dian)的(de)可(ke)靠性。
所謂“環網柜”就(jiu)(jiu)(jiu)是每(mei)個配電支路設一臺(tai)(tai)開(kai)關(guan)柜(出線(xian)開(kai)關(guan)柜),這臺(tai)(tai)開(kai)關(guan)柜的(de)母線(xian)同(tong)時(shi)就(jiu)(jiu)(jiu)是環(huan)(huan)形干(gan)線(xian)的(de)一部分。就(jiu)(jiu)(jiu)是說,環(huan)(huan)形干(gan)線(xian)是由每(mei)臺(tai)(tai)出線(xian)柜的(de)母線(xian)連接起來共同(tong)組成的(de)。每(mei)臺(tai)(tai)出線(xian)柜就(jiu)(jiu)(jiu)叫“環(huan)(huan)網(wang)(wang)柜”。實際上單獨拿(na)出一臺(tai)(tai)環(huan)(huan)網(wang)(wang)柜是看不(bu)出“環(huan)(huan)網(wang)(wang)”的(de)含義的(de)。
這(zhe)些環網(wang)(wang)柜的(de)額定(ding)電流都不大,因而(er)環網(wang)(wang)柜的(de)高壓開(kai)關(guan)一般不采用(yong)結(jie)構(gou)復雜的(de)斷(duan)(duan)路(lu)器(qi)而(er)采取結(jie)構(gou)簡單的(de)帶高壓熔斷(duan)(duan)器(qi)的(de)高壓負(fu)(fu)荷開(kai)關(guan)。也就是說,環網(wang)(wang)柜中的(de)高壓開(kai)關(guan)一般是負(fu)(fu)荷開(kai)關(guan)。環網(wang)(wang)柜用(yong)負(fu)(fu)荷開(kai)關(guan)操作正(zheng)常電流,而(er)用(yong)熔斷(duan)(duan)器(qi)切(qie)除短路(lu)電流,這(zhe)兩者結(jie)合起來取代了斷(duan)(duan)路(lu)器(qi)。當然這(zhe)只(zhi)能局限(xian)在一定(ding)容量內。
這(zhe)樣的(de)(de)(de)開(kai)(kai)關(guan)柜(ju)也(ye)完全可以(yi)用到非(fei)環網結構的(de)(de)(de)配電系統中,于是隨著這(zhe)種開(kai)(kai)關(guan)柜(ju)的(de)(de)(de)廣泛(fan)應用,“環網柜(ju)”就跳出了環網配電的(de)(de)(de)范疇而泛(fan)指以(yi)負荷開(kai)(kai)關(guan)為主開(kai)(kai)關(guan)的(de)(de)(de)高壓開(kai)(kai)關(guan)柜(ju)了。