一、箱式變電站的工作原理
箱式變電站主(zhu)要由(you)多(duo)回(hui)路高壓開關系統、鎧裝(zhuang)(zhuang)母線(xian)、安(an)裝(zhuang)(zhuang)在一個防(fang)潮、防(fang)銹、防(fang)塵、防(fang)鼠、防(fang)火、防(fang)盜、隔熱(re)、全封鎖(suo)、可(ke)挪動(dong)的鋼結(jie)構箱體(ti)內,全封鎖(suo)運行。箱式(shi)變電(dian)站外殼采取鋼板或者合金板,配(pei)有(you)雙層頂蓋(gai),隔熱(re)性好。外殼及(ji)骨架全體(ti)經由(you)防(fang)腐處理,擁(yong)有(you)長時間(jian)戶外使有(you)的前提(成套裝(zhuang)(zhuang)備(bei))。外形及(ji)顏色(se)可(ke)與(yu)環境(jing)互相協調(diao)一致(zhi)。安(an)裝(zhuang)(zhuang)利便,在箱式(shi)變電(dian)站的基(ji)礎下面設(she)有(you)電(dian)纜室(shi)(shi),而在低壓室(shi)(shi)內設(she)有(you)入(ru)孔可(ke)進入(ru)電(dian)纜室(shi)(shi)進行工(gong)作。
從體積(ji)上看,歐(ou)式箱(xiang)變(bian)因(yin)為(wei)內部安(an)裝常(chang)規開關(guan)(guan)(guan)柜(ju)及變(bian)壓(ya)(ya)(ya)(ya)(ya)器(qi)(qi),產(chan)品(pin)體積(ji)較大。美式箱(xiang)變(bian)因(yin)為(wei)采取一體化安(an)裝體積(ji)較小(電(dian)(dian)表(biao)箱(xiang))。箱(xiang)變(bian)高(gao)(gao)壓(ya)(ya)(ya)(ya)(ya)側(ce)采取負(fu)荷(he)開關(guan)(guan)(guan)加(jia)限流(liu)(liu)熔(rong)(rong)斷(duan)(duan)器(qi)(qi)維護(hu)(hu)。產(chan)生一相(xiang)熔(rong)(rong)斷(duan)(duan)器(qi)(qi)熔(rong)(rong)斷(duan)(duan)時,用熔(rong)(rong)斷(duan)(duan)器(qi)(qi)的(de)撞針使負(fu)荷(he)開關(guan)(guan)(guan)3相(xiang)同時分閘,防止缺(que)相(xiang)運行,請求負(fu)荷(he)開關(guan)(guan)(guan)擁(yong)有割(ge)斷(duan)(duan)轉(zhuan)(zhuan)移電(dian)(dian)流(liu)(liu)能(neng)力。低(di)壓(ya)(ya)(ya)(ya)(ya)側(ce)采取負(fu)荷(he)開關(guan)(guan)(guan)加(jia)限流(liu)(liu)熔(rong)(rong)斷(duan)(duan)器(qi)(qi)維護(hu)(hu),美式箱(xiang)變(bian)高(gao)(gao)壓(ya)(ya)(ya)(ya)(ya)側(ce)采取熔(rong)(rong)斷(duan)(duan)器(qi)(qi)維護(hu)(hu),而負(fu)荷(he)開關(guan)(guan)(guan)只起投切轉(zhuan)(zhuan)換以及割(ge)斷(duan)(duan)高(gao)(gao)壓(ya)(ya)(ya)(ya)(ya)負(fu)荷(he)電(dian)(dian)流(liu)(liu)的(de)功能(neng),容(rong)量較小。當(dang)高(gao)(gao)壓(ya)(ya)(ya)(ya)(ya)側(ce)呈現一相(xiang)熔(rong)(rong)絲熔(rong)(rong)斷(duan)(duan),低(di)壓(ya)(ya)(ya)(ya)(ya)側(ce)的(de)電(dian)(dian)壓(ya)(ya)(ya)(ya)(ya)就下降,塑殼自動(dong)空氣開關(guan)(guan)(guan)欠(qian)電(dian)(dian)壓(ya)(ya)(ya)(ya)(ya)維護(hu)(hu)或過電(dian)(dian)流(liu)(liu)維護(hu)(hu)就會(hui)動(dong)作,低(di)壓(ya)(ya)(ya)(ya)(ya)運行不會(hui)產(chan)生。
從產品本(ben)錢(qian)看,歐(ou)式(shi)箱(xiang)(xiang)變本(ben)錢(qian)高(gao)(gao)。從產品降價空(kong)間(jian)看,美(mei)式(shi)箱(xiang)(xiang)變還存在較大降價空(kong)間(jian),美(mei)式(shi)箱(xiang)(xiang)變的(de)高(gao)(gao)壓部份可(ke)以(yi)改型后從變壓器油(you)箱(xiang)(xiang)內挪到油(you)箱(xiang)(xiang)外,占用(yong)高(gao)(gao)壓室空(kong)間(jian)。
二、箱式變電站的用途
箱式變(bian)電(dian)站(簡稱箱變(bian))是一(yi)種(zhong)把高(gao)壓開關(guan)裝(zhuang)備配電(dian)變(bian)壓器,低壓開關(guan)裝(zhuang)備,電(dian)能(neng)(neng)計量(liang)裝(zhuang)備以(yi)及無功補償(chang)裝(zhuang)置綜合自動化系統(tong)、通信、遠動、計量(liang)、電(dian)容補償(chang)及直流電(dian)源等電(dian)氣單(dan)元組合而成在一(yi)個或幾(ji)個箱體內的緊湊型成套配電(dian)裝(zhuang)置。它適用(yong)于額定(ding)電(dian)壓10/0.4KV3相交換系統(tong)中,作為路(lu)線以(yi)及分配電(dian)能(neng)(neng)之(zhi)用(yong)。
三、箱式變電站的組成結構
箱(xiang)式變電(dian)站(zhan)又稱(cheng)為組(zu)合式箱(xiang)式變電(dian)站(zhan),其箱(xiang)內(nei)結(jie)構由(you)高壓室(shi)、低(di)壓室(shi)、變壓器室(shi)組(zu)成。緊湊型的箱(xiang)變可以將三個配電(dian)室(shi)放(fang)入同(tong)個箱(xiang)內(nei),而(er)獨立型的箱(xiang)變可以分別單獨放(fang)入不同(tong)箱(xiang)內(nei)。
1、低壓室
低(di)壓室(shi)一般有(you)低(di)壓進線柜(ju)、低(di)壓出線、低(di)壓補償柜(ju),其柜(ju)內配電(dian)裝置由低(di)壓斷路(lu)器、電(dian)流互感(gan)器、電(dian)流表、電(dian)壓表等組成的。
2、高壓室
箱(xiang)式變(bian)電(dian)(dian)站的(de)(de)高壓(ya)(ya)(ya)室一般(ban)有(you)高壓(ya)(ya)(ya)進線柜(ju)(ju)(ju)、高壓(ya)(ya)(ya)出線柜(ju)(ju)(ju)、高壓(ya)(ya)(ya)計量柜(ju)(ju)(ju)或(huo)高壓(ya)(ya)(ya)環網柜(ju)(ju)(ju),其配電(dian)(dian)裝置有(you)高壓(ya)(ya)(ya)負(fu)荷(he)(he)開關(guan)、高壓(ya)(ya)(ya)熔斷器(qi)和(he)避雷器(qi)等,可以進行停送(song)電(dian)(dian)操作并且有(you)過負(fu)荷(he)(he)和(he)短路保護。高壓(ya)(ya)(ya)配電(dian)(dian)裝置具有(you)防止(zhi)誤(wu)拉、合開關(guan)設備,帶(dai)負(fu)荷(he)(he)拉、合刀閘,帶(dai)電(dian)(dian)掛地(di)(di)線,帶(dai)地(di)(di)線合閘和(he)工(gong)作人員誤(wu)入(ru)帶(dai)電(dian)(dian)間隔的(de)(de)五防措(cuo)施。負(fu)荷(he)(he)開關(guan)和(he)熔斷器(qi)之間也應有(you)可靠(kao)的(de)(de)連鎖。
3、變壓器室
變壓器(qi)室一般采(cai)用干式電力變壓器(qi),散熱(re)性能好,過負載能力強,強迫風冷時可提(ti)高容量(liang)運行(xing)。
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(ban)都采(cai)用隔(ge)(ge)層結構,內(nei)裝(zhuang)有隔(ge)(ge)熱材(cai)料(liao),箱體底部和(he)各室之間都有冷卻(que)進出(chu)風口,采(cai)用自然風冷和(he)自動控(kong)制的(de)強(qiang)迫風冷等多(duo)種形式(shi),以保證電(dian)氣設(she)備的(de)正常散(san)熱。