一(yi)、WBYD-150KV試驗變壓器概述
YDQ系列高(gao)壓(ya)(ya)(ya)(ya)(ya)試驗(yan)(yan)變壓(ya)(ya)(ya)(ya)(ya)器是(shi)根據《試驗(yan)(yan)變壓(ya)(ya)(ya)(ya)(ya)器》標(biao)準,在油(you)浸(jin)式(shi)試驗(yan)(yan)變壓(ya)(ya)(ya)(ya)(ya)器的(de)(de)基礎上(shang)而設計生產(chan)的(de)(de)。SF6氣(qi)體具有(you)良好的(de)(de)電氣(qi)絕(jue)(jue)緣(yuan)(yuan)性能及優異的(de)(de)滅弧性能,其(qi)耐(nai)壓(ya)(ya)(ya)(ya)(ya)強(qiang)度為同一(yi)壓(ya)(ya)(ya)(ya)(ya)力下氮氣(qi)的(de)(de)2.5倍(bei)(bei)(bei),擊穿(chuan)電壓(ya)(ya)(ya)(ya)(ya)的(de)(de)空(kong)氣(qi)的(de)(de)2.5倍(bei)(bei)(bei)。在0.25MPa下與油(you)的(de)(de)擊穿(chuan)電壓(ya)(ya)(ya)(ya)(ya)相等(deng),在0.45MPa壓(ya)(ya)(ya)(ya)(ya)力下是(shi)油(you)的(de)(de)擊穿(chuan)電壓(ya)(ya)(ya)(ya)(ya)的(de)(de)2倍(bei)(bei)(bei),是(shi)一(yi)種優于(yu)油(you)的(de)(de)新(xin)一(yi)代(dai)超(chao)高(gao)壓(ya)(ya)(ya)(ya)(ya)絕(jue)(jue)緣(yuan)(yuan)介(jie)質材料。該產(chan)品技術要求完全符(fu)合《ZBK-41006-89》標(biao)準,它(ta)是(shi)油(you)浸(jin)式(shi)輕型試驗(yan)(yan)變壓(ya)(ya)(ya)(ya)(ya)器的(de)(de)換代(dai)產(chan)品。該產(chan)品具有(you)體積小、重量輕、不受氣(qi)候(hou)變化影響(xiang)、電暈小、現場(chang)搬運無需靜止(zhi)可使(shi)用,使(shi)用壽命長、免維修(xiu)等(deng)特(te)點。適用于(yu)電力系統、工(gong)礦企業、科研部門(men)等(deng)對(dui)各(ge)種高(gao)壓(ya)(ya)(ya)(ya)(ya)電氣(qi)設備、電氣(qi)元件、絕(jue)(jue)緣(yuan)(yuan)材料進行工(gong)頻(pin)或(huo)直流高(gao)壓(ya)(ya)(ya)(ya)(ya)下的(de)(de)絕(jue)(jue)緣(yuan)(yuan)強(qiang)度試驗(yan)(yan)。
二、WBYD-150KV試驗變壓器產品結構
YDQ系(xi)列高壓試驗(yan)變壓器(qi)采用單(dan)框(kuang)芯(xin)(xin)式鐵芯(xin)(xin)結(jie)構,初級繞(rao)組(zu)繞(rao)在鐵芯(xin)(xin)上,高壓繞(rao)組(zu)在外(wai),這種同軸(zhou)布(bu)置減少了(le)漏磁通,因而增(zeng)大(da)了(le)繞(rao)組(zu)間的耦(ou)合(he)。產品的外(wai)殼為圓柱灌式容器(qi)結(jie)構,能(neng)耐受0.8MPa以上壓力。其結(jie)構見(jian)圖1:
三、WBYD-150KV試驗變壓器工作原理
YDQ系列高(gao)(gao)壓(ya)(ya)試驗變(bian)壓(ya)(ya)器(qi)(qi)為單(dan)相(xiang)變(bian)壓(ya)(ya)器(qi)(qi),聯(lian)結(jie)組(zu)標號Ⅰ.Ⅰ. 用(yong)(yong)工頻220V(10kVA以(yi)(yi)上為380V)電(dian)源(yuan)接入 (為本(ben)公司生(sheng)產的(de)試驗變(bian)壓(ya)(ya)器(qi)(qi)配套(tao)專用(yong)(yong)設備,詳細資料請見其(qi)具(ju)體(ti)使(shi)用(yong)(yong)說明(ming)書)系列操(cao)作箱(xiang)(臺),經操(cao)作箱(xiang)內自偶調(diao)壓(ya)(ya)器(qi)(qi)(50kVA以(yi)(yi)上調(diao)壓(ya)(ya)器(qi)(qi)外附)調(diao)節至0~200V(或0~400V)電(dian)壓(ya)(ya)輸出至YDQ試驗變(bian)壓(ya)(ya)器(qi)(qi)的(de)初(chu)級繞(rao)組(zu),根據電(dian)磁(ci)感應原理,在試驗變(bian)壓(ya)(ya)器(qi)(qi)高(gao)(gao)壓(ya)(ya)繞(rao)組(zu)可獲(huo)得試驗所需的(de)高(gao)(gao)電(dian)壓(ya)(ya)。
單臺YDQ系列高壓試驗(yan)變(bian)壓器的工作原理圖見圖2。
單臺YDQ系列交(jiao)直(zhi)流(liu)高(gao)(gao)壓(ya)試驗變壓(ya)器的工(gong)(gong)作(zuo)原理圖(tu)見圖(tu)3,圖(tu)中高(gao)(gao)壓(ya)套管(guan)中裝有高(gao)(gao)壓(ya)硅堆,串接在高(gao)(gao)壓(ya)回路(lu)中作(zuo)半波整(zheng)流(liu),以(yi)獲(huo)得(de)直(zhi)流(liu)高(gao)(gao)電(dian)壓(ya)。當用一短(duan)路(lu)桿將(jiang)高(gao)(gao)壓(ya)硅堆短(duan)接時,可獲(huo)得(de)工(gong)(gong)頻高(gao)(gao)電(dian)壓(ya),作(zuo)為交(jiao)流(liu)輸出狀(zhuang)態;取消短(duan)路(lu)桿時,作(zuo)為直(zhi)流(liu)輸出狀(zhuang)態。
試(shi)驗變壓器高壓套管中的高壓硅堆未畫出,其(qi)原理與上圖相同。
三(san)臺(tai)試(shi)(shi)(shi)(shi)(shi)(shi)驗(yan)(yan)(yan)(yan)變(bian)(bian)(bian)壓(ya)(ya)(ya)(ya)器(qi)(qi)(qi)(qi)串級獲得更高電(dian)(dian)壓(ya)(ya)(ya)(ya)的(de)(de)接線原(yuan)理見圖(tu)4。串級高壓(ya)(ya)(ya)(ya)試(shi)(shi)(shi)(shi)(shi)(shi)驗(yan)(yan)(yan)(yan)變(bian)(bian)(bian)壓(ya)(ya)(ya)(ya)器(qi)(qi)(qi)(qi)有(you)很大的(de)(de)優越性,因(yin)為(wei)整(zheng)個試(shi)(shi)(shi)(shi)(shi)(shi)驗(yan)(yan)(yan)(yan)裝(zhuang)(zhuang)置由幾(ji)臺(tai)單(dan)臺(tai)試(shi)(shi)(shi)(shi)(shi)(shi)驗(yan)(yan)(yan)(yan)變(bian)(bian)(bian)壓(ya)(ya)(ya)(ya)器(qi)(qi)(qi)(qi)組(zu)(zu)成(cheng),單(dan)臺(tai)試(shi)(shi)(shi)(shi)(shi)(shi)驗(yan)(yan)(yan)(yan)變(bian)(bian)(bian)壓(ya)(ya)(ya)(ya)器(qi)(qi)(qi)(qi)容(rong)量(liang)小(xiao)、電(dian)(dian)壓(ya)(ya)(ya)(ya)低、重量(liang)輕,便于運輸(shu)和(he)(he)安裝(zhuang)(zhuang)。它(ta)既然可(ke)串接成(cheng)高出幾(ji)倍的(de)(de)單(dan)臺(tai)試(shi)(shi)(shi)(shi)(shi)(shi)驗(yan)(yan)(yan)(yan)變(bian)(bian)(bian)壓(ya)(ya)(ya)(ya)器(qi)(qi)(qi)(qi)輸(shu)出電(dian)(dian)壓(ya)(ya)(ya)(ya)組(zu)(zu)合(he)使用,又(you)可(ke)分(fen)(fen)開成(cheng)幾(ji)套單(dan)臺(tai)試(shi)(shi)(shi)(shi)(shi)(shi)驗(yan)(yan)(yan)(yan)變(bian)(bian)(bian)壓(ya)(ya)(ya)(ya)器(qi)(qi)(qi)(qi)單(dan)獨使用。整(zheng)套裝(zhuang)(zhuang)置投資小(xiao),經濟實(shi)惠。圖(tu)5中(zhong)(zhong)(zhong),在**級和(he)(he)**級的(de)(de)每個單(dan)元試(shi)(shi)(shi)(shi)(shi)(shi)驗(yan)(yan)(yan)(yan)變(bian)(bian)(bian)壓(ya)(ya)(ya)(ya)器(qi)(qi)(qi)(qi)中(zhong)(zhong)(zhong)都有(you)一(yi)個勵磁繞(rao)(rao)組(zu)(zu)A1、C1和(he)(he)A2、C2。在三(san)臺(tai)串級試(shi)(shi)(shi)(shi)(shi)(shi)驗(yan)(yan)(yan)(yan)變(bian)(bian)(bian)壓(ya)(ya)(ya)(ya)器(qi)(qi)(qi)(qi)基(ji)本原(yuan)理中(zhong)(zhong)(zhong),低壓(ya)(ya)(ya)(ya)電(dian)(dian)源加在試(shi)(shi)(shi)(shi)(shi)(shi)驗(yan)(yan)(yan)(yan)變(bian)(bian)(bian)壓(ya)(ya)(ya)(ya)器(qi)(qi)(qi)(qi)Ⅰ的(de)(de)初級繞(rao)(rao)組(zu)(zu)a1x1上,單(dan)臺(tai)試(shi)(shi)(shi)(shi)(shi)(shi)驗(yan)(yan)(yan)(yan)變(bian)(bian)(bian)壓(ya)(ya)(ya)(ya)器(qi)(qi)(qi)(qi)Ⅰ、Ⅱ、Ⅲ的(de)(de)輸(shu)出電(dian)(dian)壓(ya)(ya)(ya)(ya)都是(shi)V。勵磁繞(rao)(rao)組(zu)(zu)A1、C1給**級試(shi)(shi)(shi)(shi)(shi)(shi)驗(yan)(yan)(yan)(yan)變(bian)(bian)(bian)壓(ya)(ya)(ya)(ya)器(qi)(qi)(qi)(qi)Ⅱ的(de)(de)初級繞(rao)(rao)組(zu)(zu)供電(dian)(dian);**級試(shi)(shi)(shi)(shi)(shi)(shi)驗(yan)(yan)(yan)(yan)變(bian)(bian)(bian)壓(ya)(ya)(ya)(ya)器(qi)(qi)(qi)(qi)Ⅱ的(de)(de)勵磁繞(rao)(rao)組(zu)(zu)A2、C2給第三(san)級試(shi)(shi)(shi)(shi)(shi)(shi)驗(yan)(yan)(yan)(yan)變(bian)(bian)(bian)壓(ya)(ya)(ya)(ya)器(qi)(qi)(qi)(qi)Ⅲ的(de)(de)初級繞(rao)(rao)組(zu)(zu)供電(dian)(dian)。**級試(shi)(shi)(shi)(shi)(shi)(shi)驗(yan)(yan)(yan)(yan)變(bian)(bian)(bian)壓(ya)(ya)(ya)(ya)器(qi)(qi)(qi)(qi)Ⅱ和(he)(he)第三(san)級試(shi)(shi)(shi)(shi)(shi)(shi)驗(yan)(yan)(yan)(yan)變(bian)(bian)(bian)壓(ya)(ya)(ya)(ya)器(qi)(qi)(qi)(qi)Ⅲ的(de)(de)箱體(ti)分(fen)(fen)別處(chu)在對地(di)為(wei)1V和(he)(he)2V的(de)(de)高電(dian)(dian)位上,所以箱體(ti)對地(di)是(shi)絕緣的(de)(de),試(shi)(shi)(shi)(shi)(shi)(shi)驗(yan)(yan)(yan)(yan)變(bian)(bian)(bian)壓(ya)(ya)(ya)(ya)器(qi)(qi)(qi)(qi)Ⅰ的(de)(de)箱體(ti)是(shi)接地(di)的(de)(de)。這樣**級、**級、第三(san)級試(shi)(shi)(shi)(shi)(shi)(shi)驗(yan)(yan)(yan)(yan)變(bian)(bian)(bian)壓(ya)(ya)(ya)(ya)器(qi)(qi)(qi)(qi)對地(di)的(de)(de)額定(ding)輸(shu)出電(dian)(dian)壓(ya)(ya)(ya)(ya)分(fen)(fen)別為(wei)1V、2V、3V;其額定(ding)容(rong)量(liang)分(fen)(fen)別為(wei)3P、2P、1P。
YDQ系列(lie)高壓(ya)試驗變壓(ya)器做被(bei)試品的工頻耐壓(ya)試驗使用(yong)接線原(yuan)理圖(tu)見圖(tu)5。
圖中:R1—限流電阻 FRC—阻容分壓器(qi) RF—球(qiu)間隙保護電阻 G—球(qiu)間隙 CX—被(bei)試品
注:高壓尾(wei)必須可(ke)靠接地
工(gong)頻(pin)耐壓(ya)試驗(yan)中(zhong)限流(liu)(liu)電(dian)(dian)阻(zu)R1應根據(ju)試驗(yan)變壓(ya)器(qi)的(de)(de)額(e)定容量(liang)來選擇(ze)。如高壓(ya)側額(e)定輸出(chu)電(dian)(dian)流(liu)(liu)在100~300mA時(shi),可取0.5~1Ω/V(試驗(yan)電(dian)(dian)壓(ya));高壓(ya)側額(e)定輸出(chu)電(dian)(dian)流(liu)(liu)為1A以上時(shi),可取1Ω/V(試驗(yan)電(dian)(dian)壓(ya))。常用(yong)水(shui)電(dian)(dian)阻(zu)作為限流(liu)(liu)電(dian)(dian)阻(zu),管(guan)子長度可按150kV/m考慮,管(guan)子粗(cu)細應具有足夠的(de)(de)熱容量(liang)(水(shui)阻(zu)液配制方法(fa):用(yong)蒸(zheng)餾(liu)水(shui)加入適量(liang)硫(liu)酸銅(tong)配制成各種(zhong)不(bu)同的(de)(de)阻(zu)值)。
球(qiu)間(jian)隙(xi)及保(bao)護(hu)電(dian)(dian)(dian)阻(zu):當電(dian)(dian)(dian)壓超過球(qiu)間(jian)隙(xi)整定值時(一般取試(shi)(shi)(shi)驗電(dian)(dian)(dian)壓的110%~120%),球(qiu)間(jian)隙(xi)放電(dian)(dian)(dian),對被(bei)試(shi)(shi)(shi)品起(qi)到(dao)保(bao)護(hu)作用。球(qiu)間(jian)隙(xi)保(bao)護(hu)電(dian)(dian)(dian)阻(zu)可(ke)按1Ω/V(試(shi)(shi)(shi)驗電(dian)(dian)(dian)壓)選取。
在(zai)(zai)工頻耐(nai)壓(ya)(ya)(ya)試(shi)(shi)驗中,低電(dian)(dian)壓(ya)(ya)(ya)側測(ce)量(liang)電(dian)(dian)壓(ya)(ya)(ya)(儀(yi)表電(dian)(dian)壓(ya)(ya)(ya))不是(shi)非常(chang)準確(que)的(de)(de)(de),其原因是(shi)由于(yu)試(shi)(shi)驗變壓(ya)(ya)(ya)器(qi)存在(zai)(zai)著漏(lou)抗(kang),在(zai)(zai)這個漏(lou)抗(kang)上必然(ran)存在(zai)(zai)著壓(ya)(ya)(ya)降或(huo)容(rong)升,使試(shi)(shi)品(pin)上的(de)(de)(de)電(dian)(dian)壓(ya)(ya)(ya)低于(yu)或(huo)高于(yu)低壓(ya)(ya)(ya)側測(ce)量(liang)電(dian)(dian)壓(ya)(ya)(ya)表上反映(ying)出來的(de)(de)(de)電(dian)(dian)壓(ya)(ya)(ya)。工頻耐(nai)壓(ya)(ya)(ya)試(shi)(shi)驗時,被(bei)試(shi)(shi)品(pin)上的(de)(de)(de)電(dian)(dian)壓(ya)(ya)(ya)高于(yu)試(shi)(shi)驗變壓(ya)(ya)(ya)器(qi)的(de)(de)(de)輸出電(dian)(dian)壓(ya)(ya)(ya),也(ye)就是(shi)所(suo)謂容(rong)升現象。感(gan)應耐(nai)壓(ya)(ya)(ya)試(shi)(shi)驗時,試(shi)(shi)驗變壓(ya)(ya)(ya)器(qi)的(de)(de)(de)漏(lou)抗(kang)必然(ran)存在(zai)(zai)著壓(ya)(ya)(ya)降。為了準確(que)測(ce)量(liang)被(bei)試(shi)(shi)品(pin)上所(suo)施加的(de)(de)(de)電(dian)(dian)壓(ya)(ya)(ya),因此常(chang)在(zai)(zai)高壓(ya)(ya)(ya)側接入FRC阻容(rong)分壓(ya)(ya)(ya)器(qi)來測(ce)量(liang)電(dian)(dian)壓(ya)(ya)(ya)(見圖5)。
工頻耐壓試驗操作注意事項
1)試驗人員應做好分工,明確(que)相互間聯系(xi)方法。并有專門人監護(hu)現場**及觀察試品狀態(tai)。
2)被(bei)試品應先清掃干(gan)(gan)凈,并**干(gan)(gan)燥,以免(mian)損(sun)壞被(bei)試品和試驗帶來的(de)誤差。
3)對于大(da)型試(shi)(shi)驗,一般都應(ying)先(xian)進行空升(sheng)試(shi)(shi)驗。即不接試(shi)(shi)品時升(sheng)壓至試(shi)(shi)驗電(dian)壓,校對各種表計,調整球間隙。
4)升壓速度不(bu)能太快(kuai),并(bing)必(bi)須防止突然加壓。例如調壓器不(bu)在零(ling)位(wei)時突然合閘(zha)。也不(bu)能突然切斷(duan)電(dian)源,一(yi)般(ban)應在調壓器降至(zhi)零(ling)位(wei)時拉閘(zha)。
5)當電壓升(sheng)至試驗(yan)電壓時,開始計(ji)時,到1min后,迅速(su)降壓到1/3試驗(yan)電壓以(yi)下時,才能拉開電源(yuan)。
6)在升壓或(huo)耐壓試驗過程中,如(ru)發(fa)現下列(lie)不(bu)(bu)正常情(qing)況時,應立即降壓,切斷電(dian)源(yuan)。停止試驗并(bing)查(cha)明原因:①電(dian)壓表指針擺動很(hen)大;②發(fa)現絕緣燒焦或(huo)冒煙;③被試品內有(you)不(bu)(bu)正常的聲音(yin)。
7)耐壓試驗(yan)前后應測量絕(jue)緣(yuan)電阻,檢(jian)查絕(jue)緣(yuan)情況。
試(shi)(shi)驗變壓器在做被試(shi)(shi)品的直(zhi)流耐壓或泄露(lu)試(shi)(shi)驗時接線原理(li)圖如圖6。
注:此(ci)試驗(yan)應先抽出短路桿“D”,圖6中所示(shi)。
圖(tu)中:VD—高(gao)壓硅(gui)堆 R1—限流電(dian)阻 C1—高(gao)壓濾波電(dian)容(rong) FRC—阻容(rong)分(fen)壓器 CX—被(bei)試品 μA—帶保(bao)護微安表(biao)
泄(xie)露試驗(yan)中(zhong)限流(liu)(liu)電(dian)(dian)(dian)阻R1選擇在額定(ding)輸(shu)出(chu)電(dian)(dian)(dian)壓(ya)時,輸(shu)出(chu)端短路(lu)電(dian)(dian)(dian)流(liu)(liu)不超過高壓(ya)硅(gui)堆的(de)(de)*大(da)(da)整(zheng)流(liu)(liu)。如電(dian)(dian)(dian)壓(ya)硅(gui)堆的(de)(de)*大(da)(da)整(zheng)流(liu)(liu)電(dian)(dian)(dian)流(liu)(liu)為100mA時用于(yu)60kV的(de)(de)試驗(yan)裝(zhuang)置中(zhong),限流(liu)(liu)電(dian)(dian)(dian)阻按R1=60/0.1=600kΩ選擇。限流(liu)(liu)電(dian)(dian)(dian)阻還應(ying)具有(you)足夠的(de)(de)容量(liang)和沿面放電(dian)(dian)(dian)距離。
高壓濾(lv)波(bo)電(dian)容C1一般選擇在0.01~0.1μF,當(dang)被試(shi)品的(de)電(dian)容量很大(da)時,C1可省略不用。
泄(xie)露試驗(yan)的操作及注(zhu)意(yi)事項
1)試(shi)(shi)驗前應(ying)先檢查(cha)被試(shi)(shi)品(pin)是否(fou)停(ting)電,接地放電,一(yi)切對外(wai)連線(xian)是否(fou)擦干凈。要嚴防(fang)將試(shi)(shi)驗電壓加到有(you)人工作的(de)部位上去。
2)接好試(shi)驗(yan)裝置的接線(xian)后,應復(fu)查(cha)無(wu)誤(wu)后才可加壓。應特別注(zhu)意檢查(cha)高壓設備及(ji)引線(xian)與(yu)地(di)(di)、與(yu)操(cao)作人員的**距(ju)離,被試(shi)品(pin)的外殼是否(fou)可靠(kao)接地(di)(di),要按**規程中(zhong)所規定的內容進行試(shi)驗(yan)。
3)對于大電容量設備應緩(huan)慢(man)升(sheng)壓,防止被試品的充電電流燒壞微安表(biao)。必要(yao)時應分級加壓,分別讀取各級電壓下微安表(biao)的穩定(ding)讀數。
4)試驗過程(cheng)中(zhong),應(ying)(ying)密切(qie)監視被試品、試驗裝置、微安表,一旦發生擊穿、閃(shan)爍等異常現象應(ying)(ying)立(li)即降壓,切(qie)斷電源,并(bing)查明原因,詳(xiang)細記錄。
5)試(shi)驗(yan)完畢,降壓,切斷電(dian)源后應(ying)將被試(shi)品及試(shi)驗(yan)裝置(zhi)本身充分(fen)放電(dian)。
四、WBYD-150KV試驗變壓器注意事項
1、按照(zhao)您所(suo)進行(xing)的試驗(yan)接(jie)好(hao)工作線路。試驗(yan)變壓器的外殼以及(ji)操作系統的外殼必須(xu)可靠接(jie)地。試驗(yan)變壓器高壓繞組的X端(高壓尾)以及(ji)測量繞組的F端必須(xu)可靠接(jie)地。
2、做串級試(shi)驗時,**級、第(di)三(san)級試(shi)驗變(bian)壓(ya)器的(de)(de)低壓(ya)繞組(zu)的(de)(de)X端(duan),測量繞組(zu)的(de)(de)F端(duan)以及高壓(ya)繞組(zu)的(de)(de)X端(duan)(高壓(ya)尾)均接本(ben)級試(shi)驗變(bian)壓(ya)器的(de)(de)外殼。**級、第(di)三(san)級試(shi)驗變(bian)壓(ya)器的(de)(de)外殼必須通過絕(jue)緣支架接地(di)。
3、接(jie)通電源前,操作系統的(de)調壓(ya)器必須調到零位(wei)后方可接(jie)通電源,合(he)閘,開始升壓(ya)。
4、從(cong)零開(kai)始(shi)均勻旋轉調壓(ya)(ya)(ya)(ya)器手(shou)輪(lun)升(sheng)(sheng)(sheng)(sheng)壓(ya)(ya)(ya)(ya)。升(sheng)(sheng)(sheng)(sheng)壓(ya)(ya)(ya)(ya)方法(fa)(fa)有(you):快速升(sheng)(sheng)(sheng)(sheng)壓(ya)(ya)(ya)(ya)法(fa)(fa),即20s逐級(ji)升(sheng)(sheng)(sheng)(sheng)壓(ya)(ya)(ya)(ya)法(fa)(fa);慢速升(sheng)(sheng)(sheng)(sheng)壓(ya)(ya)(ya)(ya)法(fa)(fa),即60s逐級(ji)升(sheng)(sheng)(sheng)(sheng)壓(ya)(ya)(ya)(ya)法(fa)(fa);極慢速升(sheng)(sheng)(sheng)(sheng)壓(ya)(ya)(ya)(ya)法(fa)(fa)供選(xuan)用(yong)。電(dian)壓(ya)(ya)(ya)(ya)從(cong)零開(kai)始(shi)按一定(ding)(ding)的(de)(de)升(sheng)(sheng)(sheng)(sheng)壓(ya)(ya)(ya)(ya)方式和速度上升(sheng)(sheng)(sheng)(sheng)到您所(suo)需(xu)的(de)(de)額(e)定(ding)(ding)試驗(yan)電(dian)壓(ya)(ya)(ya)(ya)的(de)(de)75%后,在以(yi)每(mei)秒2%額(e)定(ding)(ding)試驗(yan)電(dian)壓(ya)(ya)(ya)(ya)的(de)(de)速度升(sheng)(sheng)(sheng)(sheng)到您所(suo)需(xu)的(de)(de)額(e)定(ding)(ding)電(dian)壓(ya)(ya)(ya)(ya),并密切注(zhu)意測量儀表的(de)(de)指示(shi)以(yi)及(ji)被(bei)試品(pin)的(de)(de)情(qing)況(kuang)(kuang)。升(sheng)(sheng)(sheng)(sheng)壓(ya)(ya)(ya)(ya)過(guo)程中(zhong)或試驗(yan)過(guo)程中(zhong)如發現測量儀表的(de)(de)指示(shi)及(ji)被(bei)試品(pin)情(qing)況(kuang)(kuang)異常,應立即降(jiang)壓(ya)(ya)(ya)(ya),切斷電(dian)源,查(cha)明(ming)情(qing)況(kuang)(kuang)。
5、試驗完畢(bi)后,應在(zai)數秒(miao)內勻速的將(jiang)調壓器(qi)返回(hui)至零位,然后切斷電源(yuan)。
6、本產品不得(de)超過額定參數使(shi)用。除試驗(yan)必須外,決不允(yun)許全電壓通電或斷電。
7、再升壓(ya)或耐壓(ya)試驗過程中,如發現以(yi)下不(bu)正常情況時(shi),應立即降(jiang)壓(ya),切斷電源(yuan),停止試驗并查(cha)明原(yuan)因。
⑴電壓(ya)表(biao)指針擺動(或數字跳動)很大(da)
⑵電流表直線(xian)上升
被試品內有不正常的聲音(yin)
8、圖1中第9項系壓(ya)力閥及壓(ya)力表,為(wei)長期關(guan)閉狀態(tai)。每6個(ge)月開閥一(yi)次,以(yi)檢查(cha)SF6壓(ya)力,應不小于(yu)0.2MPa(檢查(cha)壓(ya)力后立即關(guan)閉閥門),低于(yu)0.2MPa時應加SF6氣體(ti),以(yi)增加氣絕(jue)緣。
9、耐壓實驗(yan)前(qian)后應測量(liang)被試設備的絕(jue)緣電阻,檢查絕(jue)緣情況(kuang)。
10、當試驗變壓器長期不(bu)使用時,應放置于通(tong)風、干燥、無陽光直射(she)的(de)地方。
11、該產品不允(yun)許在(zai)高(gao)于45℃的溫度(du)下長(chang)期存放、使用(yong)、放氣。
12、運(yun)輸搬運(yun)途中不得重力沖(chong)擊。
13、產品緊固件及壓(ya)力閥、壓(ya)力表(biao)不(bu)得擅(shan)自松動(dong)。
14、使(shi)用本(ben)產品做高(gao)壓(ya)試(shi)驗(yan)時(shi),出(chu)熟悉本(ben)說明書外,還必須嚴(yan)格執行國家(jia)有(you)關標(biao)準和操作規程。可參(can)照(zhao)GB311-83《高(gao)壓(ya)輸變設備的(de)絕緣配(pei)合,高(gao)壓(ya)試(shi)驗(yan)技術(shu)》;《電氣設備預防性(xing)試(shi)驗(yan)規程》等。
五、WBYD-150KV試驗變壓器容量選擇
標稱試驗(yan)變(bian)壓器容量Pn的確定公(gong)式:Pn=kVn 2ωCt×10-9
式中:
Pn——標(biao)稱試(shi)驗(yan)變壓器容量(kVA)
Vn——試(shi)驗變壓器(qi)的額定輸出高壓的有效值(kV)
k ——**系數。k≥1,標(biao)稱電壓Vn≥1MV時,k=2;標(biao)稱電壓較低(di)時,k值可取高一些。
Ct——被試品的電容量(pF)
ω——角頻率(lv),ω=2πf, f——試驗電源的頻率(lv)
被試設備的(de)電容量(liang)Ct可由(you)交流電橋測出(chu)。Ct的(de)變(bian)化很大(da),
可由設備的(de)類型而(er)定(ding)。
典型數據如(ru)下:
簡單的棒(bang)式或懸式絕緣(yuan)子 幾十微法(fa)
簡單(dan)的分級套管 100~1000pF
電壓互感(gan)器(qi) 200 ~ 500pF
電力變壓(ya)器 < 1000kVA ~1000pF
> 1000kVA 1000~10000pF
高壓電力電纜和油浸紙絕緣 250~300pF/m
氣體絕(jue)緣 ~60pF/m
封閉變電站,SF6氣體絕緣(yuan) 100~10000Pf;
對于不(bu)同的(de)試驗電壓Vn,選擇不(bu)同的(de)(適(shi)當(dang)的(de))**系數k。
以下(xia)列出(chu)不同的Vn所選用的k值供參考。
Vn =50~100kV k = 4
Vn =150~300kV k = 3
Vn > 300kV k = 2