一、箱式變電站的工作原理
箱式變電站主要由(you)多(duo)回(hui)路(lu)高壓(ya)開(kai)關系統、鎧裝(zhuang)母線、安(an)裝(zhuang)在(zai)一個防潮、防銹、防塵、防鼠(shu)、防火、防盜、隔熱(re)、全(quan)(quan)封鎖、可(ke)挪動的鋼(gang)結構箱體內,全(quan)(quan)封鎖運行。箱式變(bian)電站(zhan)外殼采取鋼(gang)板(ban)或者合(he)金板(ban),配有雙(shuang)層(ceng)頂蓋(gai),隔熱(re)性好。外殼及骨架(jia)全(quan)(quan)體經(jing)由(you)防腐處理,擁(yong)有長時間戶外使(shi)有的前提(成套裝(zhuang)備(bei))。外形及顏(yan)色可(ke)與環境互相協(xie)調一致(zhi)。安(an)裝(zhuang)利便,在(zai)箱式變(bian)電站(zhan)的基(ji)礎(chu)下面(mian)設(she)有電纜(lan)(lan)室(shi),而在(zai)低壓(ya)室(shi)內設(she)有入孔可(ke)進(jin)入電纜(lan)(lan)室(shi)進(jin)行工作。
從體(ti)(ti)積(ji)上看,歐(ou)式(shi)箱變(bian)因為內部安裝(zhuang)常規開(kai)關(guan)柜及變(bian)壓(ya)(ya)(ya)(ya)器(qi),產品(pin)體(ti)(ti)積(ji)較(jiao)大。美式(shi)箱變(bian)因為采取(qu)一(yi)體(ti)(ti)化安裝(zhuang)體(ti)(ti)積(ji)較(jiao)小(xiao)(電(dian)表箱)。箱變(bian)高壓(ya)(ya)(ya)(ya)側(ce)采取(qu)負(fu)荷開(kai)關(guan)加限(xian)流熔(rong)斷(duan)器(qi)維(wei)護(hu)。產生一(yi)相熔(rong)斷(duan)器(qi)熔(rong)斷(duan)時(shi),用熔(rong)斷(duan)器(qi)的(de)撞針使(shi)負(fu)荷開(kai)關(guan)3相同(tong)時(shi)分閘(zha),防止(zhi)缺相運行,請求負(fu)荷開(kai)關(guan)擁(yong)有割(ge)(ge)斷(duan)轉移電(dian)流能力。低壓(ya)(ya)(ya)(ya)側(ce)采取(qu)負(fu)荷開(kai)關(guan)加限(xian)流熔(rong)斷(duan)器(qi)維(wei)護(hu),美式(shi)箱變(bian)高壓(ya)(ya)(ya)(ya)側(ce)采取(qu)熔(rong)斷(duan)器(qi)維(wei)護(hu),而負(fu)荷開(kai)關(guan)只(zhi)起投切轉換以及割(ge)(ge)斷(duan)高壓(ya)(ya)(ya)(ya)負(fu)荷電(dian)流的(de)功能,容量(liang)較(jiao)小(xiao)。當(dang)高壓(ya)(ya)(ya)(ya)側(ce)呈現一(yi)相熔(rong)絲(si)熔(rong)斷(duan),低壓(ya)(ya)(ya)(ya)側(ce)的(de)電(dian)壓(ya)(ya)(ya)(ya)就(jiu)下降,塑殼自動(dong)空氣開(kai)關(guan)欠(qian)電(dian)壓(ya)(ya)(ya)(ya)維(wei)護(hu)或過電(dian)流維(wei)護(hu)就(jiu)會動(dong)作,低壓(ya)(ya)(ya)(ya)運行不會產生。
從產品本(ben)錢看(kan),歐式箱(xiang)(xiang)變(bian)本(ben)錢高(gao)。從產品降價空間(jian)看(kan),美(mei)式箱(xiang)(xiang)變(bian)還存(cun)在較大降價空間(jian),美(mei)式箱(xiang)(xiang)變(bian)的高(gao)壓(ya)部份可以改型后從變(bian)壓(ya)器油(you)箱(xiang)(xiang)內挪(nuo)到油(you)箱(xiang)(xiang)外,占用高(gao)壓(ya)室空間(jian)。
二、箱式變電站的用途
箱(xiang)式變(bian)電(dian)(dian)站(簡稱箱(xiang)變(bian))是一種(zhong)把高壓(ya)開(kai)關(guan)裝(zhuang)(zhuang)備配電(dian)(dian)變(bian)壓(ya)器,低壓(ya)開(kai)關(guan)裝(zhuang)(zhuang)備,電(dian)(dian)能計量裝(zhuang)(zhuang)備以(yi)及(ji)(ji)無(wu)功(gong)補償(chang)裝(zhuang)(zhuang)置綜合自動化系(xi)統、通信、遠(yuan)動、計量、電(dian)(dian)容補償(chang)及(ji)(ji)直流電(dian)(dian)源(yuan)等電(dian)(dian)氣(qi)單元組合而成在(zai)一個或(huo)幾個箱(xiang)體內(nei)的緊湊型成套(tao)配電(dian)(dian)裝(zhuang)(zhuang)置。它適(shi)用于(yu)額定電(dian)(dian)壓(ya)10/0.4KV3相交換系(xi)統中,作為路線以(yi)及(ji)(ji)分配電(dian)(dian)能之用。
三、箱式變電站的組成結構
箱(xiang)(xiang)式變電(dian)站又稱為組(zu)合(he)式箱(xiang)(xiang)式變電(dian)站,其(qi)箱(xiang)(xiang)內(nei)結構由高(gao)壓(ya)(ya)室、低壓(ya)(ya)室、變壓(ya)(ya)器室組(zu)成。緊湊型(xing)的箱(xiang)(xiang)變可(ke)以將(jiang)三個配電(dian)室放入同個箱(xiang)(xiang)內(nei),而獨立型(xing)的箱(xiang)(xiang)變可(ke)以分別單(dan)獨放入不同箱(xiang)(xiang)內(nei)。
1、低壓室
低(di)壓(ya)(ya)(ya)室一般有(you)低(di)壓(ya)(ya)(ya)進線柜、低(di)壓(ya)(ya)(ya)出線、低(di)壓(ya)(ya)(ya)補償柜,其柜內(nei)配電(dian)裝置由低(di)壓(ya)(ya)(ya)斷路器、電(dian)流(liu)互感器、電(dian)流(liu)表、電(dian)壓(ya)(ya)(ya)表等(deng)組成(cheng)的。
2、高壓室
箱式變電(dian)(dian)(dian)(dian)站的高(gao)壓室一般有(you)高(gao)壓進(jin)線(xian)(xian)柜(ju)、高(gao)壓出線(xian)(xian)柜(ju)、高(gao)壓計量柜(ju)或高(gao)壓環(huan)網柜(ju),其配電(dian)(dian)(dian)(dian)裝置有(you)高(gao)壓負(fu)荷(he)(he)開關、高(gao)壓熔斷器和(he)避(bi)雷(lei)器等,可(ke)以進(jin)行停(ting)送電(dian)(dian)(dian)(dian)操作(zuo)并且有(you)過負(fu)荷(he)(he)和(he)短(duan)路(lu)保護。高(gao)壓配電(dian)(dian)(dian)(dian)裝置具有(you)防(fang)止誤拉、合開關設備,帶(dai)(dai)負(fu)荷(he)(he)拉、合刀(dao)閘,帶(dai)(dai)電(dian)(dian)(dian)(dian)掛地(di)線(xian)(xian),帶(dai)(dai)地(di)線(xian)(xian)合閘和(he)工作(zuo)人員誤入帶(dai)(dai)電(dian)(dian)(dian)(dian)間(jian)隔的五防(fang)措施。負(fu)荷(he)(he)開關和(he)熔斷器之間(jian)也應(ying)有(you)可(ke)靠的連(lian)鎖(suo)。
3、變壓器室
變壓器室一般采用干式電力變壓器,散熱(re)性(xing)能好,過負載(zai)能力強,強迫風冷時可(ke)提(ti)高容量運行。
另外箱式變還都具有電能檢測、顯示、計量的功能,并能實現相應的保護功能,還設有專用的接地導件,并有明顯的接地標志。此外為適應戶外工作環境,箱式變電站的(de)殼頂一般都(dou)采用(yong)(yong)隔層(ceng)結構,內裝有(you)隔熱材料,箱體底部(bu)和各室之(zhi)間都(dou)有(you)冷(leng)(leng)卻進(jin)出風口(kou),采用(yong)(yong)自(zi)然(ran)風冷(leng)(leng)和自(zi)動控(kong)制的(de)強(qiang)迫風冷(leng)(leng)等(deng)多種形式,以保證(zheng)電氣設備的(de)正常(chang)散(san)熱。