一(yi)、WBYD-5KVA/100KV高壓試驗變壓器概述
YDQ系列高壓(ya)試驗(yan)變壓(ya)器(qi)(qi)是根據《試驗(yan)變壓(ya)器(qi)(qi)》標準,在油(you)浸式(shi)試驗(yan)變壓(ya)器(qi)(qi)的(de)(de)(de)基礎上而設(she)計生產的(de)(de)(de)。SF6氣(qi)(qi)(qi)體(ti)具有良好的(de)(de)(de)電(dian)(dian)(dian)氣(qi)(qi)(qi)絕緣性能及優(you)異的(de)(de)(de)滅弧性能,其耐壓(ya)強(qiang)度為同一(yi)壓(ya)力下(xia)(xia)(xia)氮氣(qi)(qi)(qi)的(de)(de)(de)2.5倍(bei),擊穿電(dian)(dian)(dian)壓(ya)的(de)(de)(de)空(kong)氣(qi)(qi)(qi)的(de)(de)(de)2.5倍(bei)。在0.25MPa下(xia)(xia)(xia)與油(you)的(de)(de)(de)擊穿電(dian)(dian)(dian)壓(ya)相等,在0.45MPa壓(ya)力下(xia)(xia)(xia)是油(you)的(de)(de)(de)擊穿電(dian)(dian)(dian)壓(ya)的(de)(de)(de)2倍(bei),是一(yi)種優(you)于(yu)油(you)的(de)(de)(de)新一(yi)代(dai)超(chao)高壓(ya)絕緣介質材(cai)料。該(gai)產品(pin)(pin)技術要求(qiu)完全符合《ZBK-41006-89》標準,它(ta)是油(you)浸式(shi)輕(qing)型試驗(yan)變壓(ya)器(qi)(qi)的(de)(de)(de)換(huan)代(dai)產品(pin)(pin)。該(gai)產品(pin)(pin)具有體(ti)積小(xiao)、重量輕(qing)、不受氣(qi)(qi)(qi)候變化影響、電(dian)(dian)(dian)暈(yun)小(xiao)、現場搬運無需靜止可(ke)使用,使用壽命(ming)長、免維(wei)修(xiu)等特點。適用于(yu)電(dian)(dian)(dian)力系統(tong)、工(gong)礦(kuang)企業、科(ke)研部門等對各種高壓(ya)電(dian)(dian)(dian)氣(qi)(qi)(qi)設(she)備(bei)、電(dian)(dian)(dian)氣(qi)(qi)(qi)元件(jian)、絕緣材(cai)料進行工(gong)頻或直流高壓(ya)下(xia)(xia)(xia)的(de)(de)(de)絕緣強(qiang)度試驗(yan)。
二、WBYD-5KVA/100KV高壓試驗變壓器產品結構
YDQ系列高(gao)壓試(shi)驗變壓器采用單框(kuang)芯式鐵芯結構(gou),初級(ji)繞(rao)(rao)(rao)組繞(rao)(rao)(rao)在鐵芯上(shang),高(gao)壓繞(rao)(rao)(rao)組在外,這種同軸布置(zhi)減少了漏(lou)磁通(tong),因(yin)而增(zeng)大了繞(rao)(rao)(rao)組間的(de)耦合。產品的(de)外殼為(wei)圓柱灌式容器結構(gou),能耐受0.8MPa以(yi)上(shang)壓力。其結構(gou)見圖1:
三、WBYD-5KVA/100KV高壓試驗變壓器工作原理
YDQ系(xi)列(lie)高壓(ya)(ya)(ya)(ya)試驗變(bian)(bian)壓(ya)(ya)(ya)(ya)器(qi)(qi)為(wei)單相變(bian)(bian)壓(ya)(ya)(ya)(ya)器(qi)(qi),聯結(jie)組(zu)(zu)標號Ⅰ.Ⅰ. 用工頻220V(10kVA以(yi)上為(wei)380V)電(dian)(dian)源接入(ru) (為(wei)本公司生產(chan)的(de)試驗變(bian)(bian)壓(ya)(ya)(ya)(ya)器(qi)(qi)配(pei)套專用設備,詳(xiang)細資料請見其(qi)具體使用說明書(shu))系(xi)列(lie)操作箱(臺(tai)),經操作箱內自(zi)偶(ou)調壓(ya)(ya)(ya)(ya)器(qi)(qi)(50kVA以(yi)上調壓(ya)(ya)(ya)(ya)器(qi)(qi)外(wai)附)調節至0~200V(或0~400V)電(dian)(dian)壓(ya)(ya)(ya)(ya)輸(shu)出至YDQ試驗變(bian)(bian)壓(ya)(ya)(ya)(ya)器(qi)(qi)的(de)初(chu)級繞組(zu)(zu),根據(ju)電(dian)(dian)磁感應原(yuan)理,在試驗變(bian)(bian)壓(ya)(ya)(ya)(ya)器(qi)(qi)高壓(ya)(ya)(ya)(ya)繞組(zu)(zu)可(ke)獲得試驗所需的(de)高電(dian)(dian)壓(ya)(ya)(ya)(ya)。
單臺YDQ系列高壓試驗(yan)變壓器的工(gong)作原理圖(tu)見(jian)圖(tu)2。
單臺YDQ系列交(jiao)直(zhi)流(liu)高壓(ya)(ya)試(shi)驗變壓(ya)(ya)器的工(gong)作(zuo)原理圖(tu)(tu)見圖(tu)(tu)3,圖(tu)(tu)中高壓(ya)(ya)套管中裝有高壓(ya)(ya)硅堆(dui),串接在高壓(ya)(ya)回路(lu)中作(zuo)半波(bo)整流(liu),以獲得直(zhi)流(liu)高電壓(ya)(ya)。當用一短(duan)路(lu)桿將高壓(ya)(ya)硅堆(dui)短(duan)接時,可獲得工(gong)頻高電壓(ya)(ya),作(zuo)為交(jiao)流(liu)輸出狀態;取消短(duan)路(lu)桿時,作(zuo)為直(zhi)流(liu)輸出狀態。
試驗變壓器高壓套(tao)管中(zhong)的(de)高壓硅堆未(wei)畫出,其(qi)原理(li)與上圖(tu)相同。
三(san)臺(tai)試(shi)(shi)(shi)(shi)驗(yan)(yan)(yan)(yan)(yan)變(bian)(bian)(bian)(bian)(bian)壓(ya)(ya)器(qi)串(chuan)級(ji)(ji)(ji)(ji)(ji)獲得(de)更高(gao)電(dian)(dian)壓(ya)(ya)的(de)(de)接線(xian)原理見圖4。串(chuan)級(ji)(ji)(ji)(ji)(ji)高(gao)壓(ya)(ya)試(shi)(shi)(shi)(shi)驗(yan)(yan)(yan)(yan)(yan)變(bian)(bian)(bian)(bian)(bian)壓(ya)(ya)器(qi)有很大(da)的(de)(de)優(you)越性,因(yin)為整(zheng)個試(shi)(shi)(shi)(shi)驗(yan)(yan)(yan)(yan)(yan)裝置(zhi)(zhi)由幾(ji)臺(tai)單臺(tai)試(shi)(shi)(shi)(shi)驗(yan)(yan)(yan)(yan)(yan)變(bian)(bian)(bian)(bian)(bian)壓(ya)(ya)器(qi)組(zu)(zu)成,單臺(tai)試(shi)(shi)(shi)(shi)驗(yan)(yan)(yan)(yan)(yan)變(bian)(bian)(bian)(bian)(bian)壓(ya)(ya)器(qi)容量小、電(dian)(dian)壓(ya)(ya)低(di)、重(zhong)量輕,便于運(yun)輸(shu)和安裝。它既然可(ke)串(chuan)接成高(gao)出(chu)幾(ji)倍的(de)(de)單臺(tai)試(shi)(shi)(shi)(shi)驗(yan)(yan)(yan)(yan)(yan)變(bian)(bian)(bian)(bian)(bian)壓(ya)(ya)器(qi)輸(shu)出(chu)電(dian)(dian)壓(ya)(ya)組(zu)(zu)合(he)使用(yong),又可(ke)分(fen)(fen)開成幾(ji)套(tao)單臺(tai)試(shi)(shi)(shi)(shi)驗(yan)(yan)(yan)(yan)(yan)變(bian)(bian)(bian)(bian)(bian)壓(ya)(ya)器(qi)單獨(du)使用(yong)。整(zheng)套(tao)裝置(zhi)(zhi)投資小,經濟實惠。圖5中(zhong),在(zai)**級(ji)(ji)(ji)(ji)(ji)和**級(ji)(ji)(ji)(ji)(ji)的(de)(de)每(mei)個單元試(shi)(shi)(shi)(shi)驗(yan)(yan)(yan)(yan)(yan)變(bian)(bian)(bian)(bian)(bian)壓(ya)(ya)器(qi)中(zhong)都(dou)有一(yi)個勵磁(ci)繞(rao)(rao)組(zu)(zu)A1、C1和A2、C2。在(zai)三(san)臺(tai)串(chuan)級(ji)(ji)(ji)(ji)(ji)試(shi)(shi)(shi)(shi)驗(yan)(yan)(yan)(yan)(yan)變(bian)(bian)(bian)(bian)(bian)壓(ya)(ya)器(qi)基本原理中(zhong),低(di)壓(ya)(ya)電(dian)(dian)源加在(zai)試(shi)(shi)(shi)(shi)驗(yan)(yan)(yan)(yan)(yan)變(bian)(bian)(bian)(bian)(bian)壓(ya)(ya)器(qi)Ⅰ的(de)(de)初(chu)級(ji)(ji)(ji)(ji)(ji)繞(rao)(rao)組(zu)(zu)a1x1上,單臺(tai)試(shi)(shi)(shi)(shi)驗(yan)(yan)(yan)(yan)(yan)變(bian)(bian)(bian)(bian)(bian)壓(ya)(ya)器(qi)Ⅰ、Ⅱ、Ⅲ的(de)(de)輸(shu)出(chu)電(dian)(dian)壓(ya)(ya)都(dou)是(shi)V。勵磁(ci)繞(rao)(rao)組(zu)(zu)A1、C1給**級(ji)(ji)(ji)(ji)(ji)試(shi)(shi)(shi)(shi)驗(yan)(yan)(yan)(yan)(yan)變(bian)(bian)(bian)(bian)(bian)壓(ya)(ya)器(qi)Ⅱ的(de)(de)初(chu)級(ji)(ji)(ji)(ji)(ji)繞(rao)(rao)組(zu)(zu)供電(dian)(dian);**級(ji)(ji)(ji)(ji)(ji)試(shi)(shi)(shi)(shi)驗(yan)(yan)(yan)(yan)(yan)變(bian)(bian)(bian)(bian)(bian)壓(ya)(ya)器(qi)Ⅱ的(de)(de)勵磁(ci)繞(rao)(rao)組(zu)(zu)A2、C2給第(di)三(san)級(ji)(ji)(ji)(ji)(ji)試(shi)(shi)(shi)(shi)驗(yan)(yan)(yan)(yan)(yan)變(bian)(bian)(bian)(bian)(bian)壓(ya)(ya)器(qi)Ⅲ的(de)(de)初(chu)級(ji)(ji)(ji)(ji)(ji)繞(rao)(rao)組(zu)(zu)供電(dian)(dian)。**級(ji)(ji)(ji)(ji)(ji)試(shi)(shi)(shi)(shi)驗(yan)(yan)(yan)(yan)(yan)變(bian)(bian)(bian)(bian)(bian)壓(ya)(ya)器(qi)Ⅱ和第(di)三(san)級(ji)(ji)(ji)(ji)(ji)試(shi)(shi)(shi)(shi)驗(yan)(yan)(yan)(yan)(yan)變(bian)(bian)(bian)(bian)(bian)壓(ya)(ya)器(qi)Ⅲ的(de)(de)箱(xiang)體分(fen)(fen)別(bie)(bie)(bie)處在(zai)對地(di)為1V和2V的(de)(de)高(gao)電(dian)(dian)位上,所(suo)以(yi)箱(xiang)體對地(di)是(shi)絕緣的(de)(de),試(shi)(shi)(shi)(shi)驗(yan)(yan)(yan)(yan)(yan)變(bian)(bian)(bian)(bian)(bian)壓(ya)(ya)器(qi)Ⅰ的(de)(de)箱(xiang)體是(shi)接地(di)的(de)(de)。這樣**級(ji)(ji)(ji)(ji)(ji)、**級(ji)(ji)(ji)(ji)(ji)、第(di)三(san)級(ji)(ji)(ji)(ji)(ji)試(shi)(shi)(shi)(shi)驗(yan)(yan)(yan)(yan)(yan)變(bian)(bian)(bian)(bian)(bian)壓(ya)(ya)器(qi)對地(di)的(de)(de)額(e)(e)定輸(shu)出(chu)電(dian)(dian)壓(ya)(ya)分(fen)(fen)別(bie)(bie)(bie)為1V、2V、3V;其(qi)額(e)(e)定容量分(fen)(fen)別(bie)(bie)(bie)為3P、2P、1P。
YDQ系(xi)列高(gao)壓試驗變壓器做被試品(pin)的工頻耐壓試驗使(shi)用接線原(yuan)理圖(tu)(tu)見圖(tu)(tu)5。
圖中(zhong):R1—限流(liu)電(dian)阻(zu) FRC—阻(zu)容分壓器 RF—球間(jian)隙保(bao)護電(dian)阻(zu) G—球間(jian)隙 CX—被試(shi)品
注:高壓尾必須可(ke)靠接地
工頻耐壓(ya)試(shi)(shi)驗(yan)(yan)(yan)中(zhong)限(xian)流(liu)(liu)電(dian)阻R1應根(gen)據試(shi)(shi)驗(yan)(yan)(yan)變壓(ya)器(qi)的(de)額定容量來選擇。如高壓(ya)側額定輸(shu)出電(dian)流(liu)(liu)在100~300mA時,可取0.5~1Ω/V(試(shi)(shi)驗(yan)(yan)(yan)電(dian)壓(ya));高壓(ya)側額定輸(shu)出電(dian)流(liu)(liu)為1A以上(shang)時,可取1Ω/V(試(shi)(shi)驗(yan)(yan)(yan)電(dian)壓(ya))。常用水(shui)電(dian)阻作為限(xian)流(liu)(liu)電(dian)阻,管(guan)子長度(du)可按150kV/m考慮,管(guan)子粗細(xi)應具有足(zu)夠的(de)熱容量(水(shui)阻液配制方法:用蒸餾水(shui)加入適量硫酸(suan)銅配制成各種不同的(de)阻值)。
球間(jian)(jian)(jian)隙(xi)及保護電(dian)(dian)(dian)阻:當(dang)電(dian)(dian)(dian)壓超(chao)過球間(jian)(jian)(jian)隙(xi)整定值(zhi)時(一(yi)般取試(shi)驗電(dian)(dian)(dian)壓的(de)110%~120%),球間(jian)(jian)(jian)隙(xi)放電(dian)(dian)(dian),對被試(shi)品起(qi)到保護作用。球間(jian)(jian)(jian)隙(xi)保護電(dian)(dian)(dian)阻可按1Ω/V(試(shi)驗電(dian)(dian)(dian)壓)選取。
在(zai)工(gong)頻耐(nai)(nai)壓(ya)(ya)(ya)(ya)試(shi)驗中,低(di)電壓(ya)(ya)(ya)(ya)側(ce)(ce)測(ce)(ce)量電壓(ya)(ya)(ya)(ya)(儀表電壓(ya)(ya)(ya)(ya))不是非常(chang)(chang)準確的(de)(de)(de),其原因是由于試(shi)驗變(bian)(bian)壓(ya)(ya)(ya)(ya)器存(cun)(cun)在(zai)著(zhu)漏抗,在(zai)這個漏抗上必然存(cun)(cun)在(zai)著(zhu)壓(ya)(ya)(ya)(ya)降或(huo)容(rong)升,使試(shi)品上的(de)(de)(de)電壓(ya)(ya)(ya)(ya)低(di)于或(huo)高(gao)(gao)于低(di)壓(ya)(ya)(ya)(ya)側(ce)(ce)測(ce)(ce)量電壓(ya)(ya)(ya)(ya)表上反映出來的(de)(de)(de)電壓(ya)(ya)(ya)(ya)。工(gong)頻耐(nai)(nai)壓(ya)(ya)(ya)(ya)試(shi)驗時(shi),被(bei)試(shi)品上的(de)(de)(de)電壓(ya)(ya)(ya)(ya)高(gao)(gao)于試(shi)驗變(bian)(bian)壓(ya)(ya)(ya)(ya)器的(de)(de)(de)輸出電壓(ya)(ya)(ya)(ya),也就是所謂(wei)容(rong)升現象。感(gan)應耐(nai)(nai)壓(ya)(ya)(ya)(ya)試(shi)驗時(shi),試(shi)驗變(bian)(bian)壓(ya)(ya)(ya)(ya)器的(de)(de)(de)漏抗必然存(cun)(cun)在(zai)著(zhu)壓(ya)(ya)(ya)(ya)降。為了準確測(ce)(ce)量被(bei)試(shi)品上所施加(jia)的(de)(de)(de)電壓(ya)(ya)(ya)(ya),因此(ci)常(chang)(chang)在(zai)高(gao)(gao)壓(ya)(ya)(ya)(ya)側(ce)(ce)接入FRC阻容(rong)分壓(ya)(ya)(ya)(ya)器來測(ce)(ce)量電壓(ya)(ya)(ya)(ya)(見圖5)。
工頻(pin)耐壓試(shi)驗(yan)操(cao)作注(zhu)意事項
1)試(shi)驗人員應做好分(fen)工,明確相(xiang)互間聯系方法。并有專(zhuan)門人監護現場**及觀察(cha)試(shi)品(pin)狀態(tai)。
2)被試品(pin)應先清掃干凈,并**干燥,以免損(sun)壞(huai)被試品(pin)和試驗(yan)帶(dai)來的誤差。
3)對(dui)于(yu)大型試(shi)驗(yan),一(yi)般都應先進(jin)行空(kong)升(sheng)試(shi)驗(yan)。即不接試(shi)品(pin)時(shi)升(sheng)壓至試(shi)驗(yan)電壓,校對(dui)各種表計(ji),調整球間隙。
4)升壓速度不(bu)能(neng)太(tai)快,并必須防止(zhi)突(tu)然(ran)加壓。例如調壓器不(bu)在(zai)(zai)零位(wei)(wei)時突(tu)然(ran)合閘(zha)。也(ye)不(bu)能(neng)突(tu)然(ran)切(qie)斷(duan)電源,一般應(ying)在(zai)(zai)調壓器降至零位(wei)(wei)時拉(la)閘(zha)。
5)當(dang)電壓(ya)升(sheng)至試(shi)驗電壓(ya)時(shi),開始計(ji)時(shi),到1min后(hou),迅速降壓(ya)到1/3試(shi)驗電壓(ya)以(yi)下時(shi),才能(neng)拉開電源。
6)在升(sheng)壓(ya)(ya)或耐壓(ya)(ya)試驗過程中,如發(fa)現下列(lie)不正(zheng)常(chang)情況時,應立即降(jiang)壓(ya)(ya),切斷電源。停止(zhi)試驗并(bing)查明(ming)原因:①電壓(ya)(ya)表指針擺動很大;②發(fa)現絕緣燒焦或冒煙;③被(bei)試品內(nei)有不正(zheng)常(chang)的聲音。
7)耐壓試驗前后(hou)應測量絕(jue)緣(yuan)電阻,檢查(cha)絕(jue)緣(yuan)情況(kuang)。
試(shi)驗變(bian)壓器在做(zuo)被試(shi)品(pin)的直流耐(nai)壓或泄露試(shi)驗時接線原理圖如圖6。
注:此試驗應先抽(chou)出短路桿“D”,圖6中所示。
圖中:VD—高壓(ya)(ya)硅(gui)堆 R1—限流電(dian)阻 C1—高壓(ya)(ya)濾波電(dian)容 FRC—阻容分(fen)壓(ya)(ya)器(qi) CX—被試品 μA—帶保(bao)護微安(an)表(biao)
泄露試(shi)驗中(zhong)限流(liu)電(dian)阻R1選擇(ze)在額定輸(shu)出(chu)電(dian)壓時(shi),輸(shu)出(chu)端(duan)短(duan)路電(dian)流(liu)不超過高壓硅堆的(de)(de)*大(da)整流(liu)。如電(dian)壓硅堆的(de)(de)*大(da)整流(liu)電(dian)流(liu)為100mA時(shi)用(yong)于60kV的(de)(de)試(shi)驗裝置中(zhong),限流(liu)電(dian)阻按R1=60/0.1=600kΩ選擇(ze)。限流(liu)電(dian)阻還應(ying)具有(you)足夠的(de)(de)容量(liang)和沿面放電(dian)距離(li)。
高壓濾波電容C1一般選擇在0.01~0.1μF,當被試品(pin)的電容量很大時,C1可省略不(bu)用(yong)。
泄(xie)露試驗的操作(zuo)及(ji)注意事項
1)試(shi)(shi)(shi)驗前應先檢查被試(shi)(shi)(shi)品(pin)是否停電(dian)(dian),接(jie)地放電(dian)(dian),一切對(dui)外連(lian)線是否擦干凈。要嚴防將試(shi)(shi)(shi)驗電(dian)(dian)壓(ya)加到(dao)有人工作的(de)部(bu)位(wei)上去。
2)接好(hao)試(shi)驗裝置的接線后,應復查無誤后才可(ke)加(jia)壓。應特別注意檢(jian)查高壓設備(bei)及引線與(yu)地、與(yu)操(cao)作人員的**距離,被試(shi)品的外殼是(shi)否(fou)可(ke)靠接地,要(yao)按**規程中所規定的內(nei)容進行試(shi)驗。
3)對于大電(dian)(dian)容(rong)量設備應緩慢升壓,防止被(bei)試品的充(chong)電(dian)(dian)電(dian)(dian)流燒壞微安(an)表。必要時(shi)應分級(ji)(ji)加壓,分別讀取各級(ji)(ji)電(dian)(dian)壓下微安(an)表的穩定讀數。
4)試驗過程中,應密切監視被(bei)試品、試驗裝置(zhi)、微安表,一(yi)旦(dan)發(fa)生擊穿、閃(shan)爍(shuo)等(deng)異常(chang)現象應立即(ji)降壓,切斷電源,并(bing)查(cha)明(ming)原因,詳細(xi)記錄(lu)。
5)試驗完畢,降壓(ya),切斷(duan)電源后應將被試品及試驗裝置本(ben)身充(chong)分放電。
四、WBYD-5KVA/100KV高壓試驗變壓器注意事項
1、按(an)照您所進行的(de)試驗(yan)(yan)接(jie)(jie)好工作線路。試驗(yan)(yan)變壓(ya)器(qi)的(de)外(wai)殼(ke)以及操作系統的(de)外(wai)殼(ke)必須可(ke)靠(kao)接(jie)(jie)地(di)。試驗(yan)(yan)變壓(ya)器(qi)高(gao)壓(ya)繞組(zu)的(de)X端(高(gao)壓(ya)尾(wei))以及測(ce)量(liang)繞組(zu)的(de)F端必須可(ke)靠(kao)接(jie)(jie)地(di)。
2、做(zuo)串級(ji)試驗時,**級(ji)、第(di)三級(ji)試驗變壓器的(de)低壓繞(rao)(rao)組(zu)的(de)X端(duan),測(ce)量繞(rao)(rao)組(zu)的(de)F端(duan)以及高壓繞(rao)(rao)組(zu)的(de)X端(duan)(高壓尾)均(jun)接本級(ji)試驗變壓器的(de)外殼(ke)。**級(ji)、第(di)三級(ji)試驗變壓器的(de)外殼(ke)必須通過絕緣支(zhi)架接地。
3、接通電(dian)源前,操作系統的調壓器(qi)必(bi)須調到零位后(hou)方可接通電(dian)源,合閘,開始(shi)升(sheng)壓。
4、從(cong)零(ling)開(kai)始均勻旋(xuan)轉調壓(ya)(ya)(ya)器手輪升(sheng)(sheng)(sheng)壓(ya)(ya)(ya)。升(sheng)(sheng)(sheng)壓(ya)(ya)(ya)方法(fa)有(you):快速(su)升(sheng)(sheng)(sheng)壓(ya)(ya)(ya)法(fa),即(ji)(ji)20s逐級(ji)升(sheng)(sheng)(sheng)壓(ya)(ya)(ya)法(fa);慢速(su)升(sheng)(sheng)(sheng)壓(ya)(ya)(ya)法(fa),即(ji)(ji)60s逐級(ji)升(sheng)(sheng)(sheng)壓(ya)(ya)(ya)法(fa);極慢速(su)升(sheng)(sheng)(sheng)壓(ya)(ya)(ya)法(fa)供選用。電(dian)壓(ya)(ya)(ya)從(cong)零(ling)開(kai)始按一定(ding)的升(sheng)(sheng)(sheng)壓(ya)(ya)(ya)方式和速(su)度上升(sheng)(sheng)(sheng)到您所需的額定(ding)試驗(yan)電(dian)壓(ya)(ya)(ya)的75%后(hou),在以每秒2%額定(ding)試驗(yan)電(dian)壓(ya)(ya)(ya)的速(su)度升(sheng)(sheng)(sheng)到您所需的額定(ding)電(dian)壓(ya)(ya)(ya),并(bing)密(mi)切注意(yi)測量儀表(biao)的指示以及被試品的情況(kuang)。升(sheng)(sheng)(sheng)壓(ya)(ya)(ya)過程(cheng)中(zhong)(zhong)或(huo)試驗(yan)過程(cheng)中(zhong)(zhong)如發現測量儀表(biao)的指示及被試品情況(kuang)異常,應立即(ji)(ji)降壓(ya)(ya)(ya),切斷電(dian)源,查明(ming)情況(kuang)。
5、試驗(yan)完畢后(hou),應(ying)在(zai)數秒內勻速的(de)將調壓器返回至零位,然后(hou)切(qie)斷電(dian)源(yuan)。
6、本產品(pin)不得超過額定參數(shu)使用。除試驗必須外,決不允許全電(dian)(dian)壓(ya)通電(dian)(dian)或斷電(dian)(dian)。
7、再(zai)升(sheng)壓(ya)或耐壓(ya)試(shi)驗過程中,如發(fa)現以下不正(zheng)常情況時,應立即降壓(ya),切(qie)斷電源,停止試(shi)驗并查明(ming)原因。
⑴電壓表指針擺動(dong)(或數字跳動(dong))很(hen)大
⑵電流表直線上升
被(bei)試(shi)品內有不正常(chang)的聲音(yin)
8、圖1中第9項系(xi)壓(ya)力(li)閥及壓(ya)力(li)表(biao),為長期關閉狀態。每(mei)6個(ge)月開閥一次,以檢(jian)查SF6壓(ya)力(li),應不小(xiao)于0.2MPa(檢(jian)查壓(ya)力(li)后(hou)立即關閉閥門),低于0.2MPa時應加SF6氣(qi)體,以增加氣(qi)絕(jue)緣。
9、耐壓實驗前后應測量被(bei)試設備的絕緣電(dian)阻(zu),檢查(cha)絕緣情況。
10、當(dang)試驗變壓(ya)器長期不使(shi)用時,應放置于通風、干燥、無陽光直射的地方。
11、該(gai)產品(pin)不(bu)允許在高于45℃的溫度下長期存放、使用(yong)、放氣(qi)。
12、運輸搬(ban)運途中不得重(zhong)力沖(chong)擊。
13、產品緊固件及壓力(li)閥、壓力(li)表不(bu)得(de)擅自松動。
14、使用本(ben)產品做高(gao)(gao)壓試驗時(shi),出熟(shu)悉本(ben)說明書外,還必(bi)須(xu)嚴格執行國(guo)家有(you)關標準和操(cao)作(zuo)規程。可參照GB311-83《高(gao)(gao)壓輸變設(she)備(bei)的絕(jue)緣配合,高(gao)(gao)壓試驗技術》;《電氣設(she)備(bei)預(yu)防性試驗規程》等。
五、WBYD-5KVA/100KV高壓試驗變壓器容量選擇
標稱試驗變壓器容量Pn的(de)確定(ding)公式(shi):Pn=kVn 2ωCt×10-9
式中:
Pn——標(biao)稱試驗變壓器容量(kVA)
Vn——試驗(yan)變壓器的額定輸出高壓的有效值(kV)
k ——**系數。k≥1,標稱電壓Vn≥1MV時(shi),k=2;標稱電壓較低時(shi),k值可取(qu)高一些。
Ct——被試品的電(dian)容量(pF)
ω——角(jiao)頻(pin)率(lv),ω=2πf, f——試驗電源的頻(pin)率(lv)
被試設備(bei)的電容量Ct可由交流電橋測出。Ct的變化很大,
可由設備的類型(xing)而定。
典型(xing)數(shu)據如下:
簡單的棒式或懸式絕緣子 幾十微法
簡單的分級(ji)套管(guan) 100~1000pF
電壓(ya)互感器(qi) 200 ~ 500pF
電力變壓器 < 1000kVA ~1000pF
> 1000kVA 1000~10000pF
高壓電力電纜和(he)油浸紙絕緣 250~300pF/m
氣(qi)體絕緣 ~60pF/m
封閉變電(dian)站,SF6氣體(ti)絕緣 100~10000Pf;
對于不(bu)(bu)同的(de)試驗電壓(ya)Vn,選擇不(bu)(bu)同的(de)(適(shi)當的(de))**系(xi)數k。
以下列出(chu)不同(tong)的Vn所選用的k值供(gong)參考。
Vn =50~100kV k = 4
Vn =150~300kV k = 3
Vn > 300kV k = 2