一、WBYD-20KVA/100KV工頻交流試驗變壓器概述
YDQ系(xi)列(lie)高壓試(shi)驗(yan)變壓器(qi)是(shi)根據《試(shi)驗(yan)變壓器(qi)》標準(zhun),在油(you)(you)浸(jin)式試(shi)驗(yan)變壓器(qi)的(de)(de)基礎上而設計生產(chan)(chan)(chan)的(de)(de)。SF6氣體具(ju)有良好(hao)的(de)(de)電(dian)氣絕(jue)(jue)緣(yuan)性(xing)能及(ji)優異的(de)(de)滅(mie)弧性(xing)能,其耐(nai)壓強度(du)(du)為同一壓力下(xia)(xia)(xia)氮氣的(de)(de)2.5倍(bei),擊(ji)穿(chuan)電(dian)壓的(de)(de)空(kong)氣的(de)(de)2.5倍(bei)。在0.25MPa下(xia)(xia)(xia)與油(you)(you)的(de)(de)擊(ji)穿(chuan)電(dian)壓相等(deng),在0.45MPa壓力下(xia)(xia)(xia)是(shi)油(you)(you)的(de)(de)擊(ji)穿(chuan)電(dian)壓的(de)(de)2倍(bei),是(shi)一種優于(yu)油(you)(you)的(de)(de)新一代超高壓絕(jue)(jue)緣(yuan)介(jie)質材(cai)料。該(gai)(gai)產(chan)(chan)(chan)品技術要求完全(quan)符合《ZBK-41006-89》標準(zhun),它(ta)是(shi)油(you)(you)浸(jin)式輕型試(shi)驗(yan)變壓器(qi)的(de)(de)換代產(chan)(chan)(chan)品。該(gai)(gai)產(chan)(chan)(chan)品具(ju)有體積(ji)小、重量輕、不受氣候(hou)變化影響、電(dian)暈小、現場搬運無需(xu)靜止可使用,使用壽(shou)命長、免(mian)維修等(deng)特點。適用于(yu)電(dian)力系(xi)統、工礦(kuang)企業、科研部門等(deng)對各種高壓電(dian)氣設備(bei)、電(dian)氣元件(jian)、絕(jue)(jue)緣(yuan)材(cai)料進行工頻或直流(liu)高壓下(xia)(xia)(xia)的(de)(de)絕(jue)(jue)緣(yuan)強度(du)(du)試(shi)驗(yan)。
二、WBYD-20KVA/100KV工頻交流試驗變壓器產品結構
YDQ系列高壓(ya)試驗變壓(ya)器(qi)采用單框芯(xin)式鐵(tie)芯(xin)結構(gou),初(chu)級繞組(zu)繞在(zai)鐵(tie)芯(xin)上(shang)(shang),高壓(ya)繞組(zu)在(zai)外,這種同(tong)軸布置減少(shao)了(le)漏磁通,因(yin)而增大了(le)繞組(zu)間的耦(ou)合。產品(pin)的外殼為圓柱灌式容器(qi)結構(gou),能耐(nai)受0.8MPa以上(shang)(shang)壓(ya)力。其結構(gou)見圖1:
三、WBYD-20KVA/100KV工頻交流試驗變壓器工作原理
YDQ系列(lie)(lie)高(gao)壓(ya)(ya)(ya)(ya)(ya)試(shi)(shi)(shi)驗(yan)變壓(ya)(ya)(ya)(ya)(ya)器(qi)為單相變壓(ya)(ya)(ya)(ya)(ya)器(qi),聯(lian)結組標號Ⅰ.Ⅰ. 用(yong)工頻220V(10kVA以(yi)上(shang)為380V)電源接入 (為本(ben)公司生(sheng)產(chan)的(de)試(shi)(shi)(shi)驗(yan)變壓(ya)(ya)(ya)(ya)(ya)器(qi)配套專用(yong)設(she)備(bei),詳細資(zi)料請見其具(ju)體使用(yong)說明書(shu))系列(lie)(lie)操作箱(臺),經(jing)操作箱內自偶調(diao)壓(ya)(ya)(ya)(ya)(ya)器(qi)(50kVA以(yi)上(shang)調(diao)壓(ya)(ya)(ya)(ya)(ya)器(qi)外(wai)附)調(diao)節至0~200V(或0~400V)電壓(ya)(ya)(ya)(ya)(ya)輸(shu)出至YDQ試(shi)(shi)(shi)驗(yan)變壓(ya)(ya)(ya)(ya)(ya)器(qi)的(de)初級繞(rao)組,根據電磁(ci)感應原理,在試(shi)(shi)(shi)驗(yan)變壓(ya)(ya)(ya)(ya)(ya)器(qi)高(gao)壓(ya)(ya)(ya)(ya)(ya)繞(rao)組可獲得試(shi)(shi)(shi)驗(yan)所(suo)需的(de)高(gao)電壓(ya)(ya)(ya)(ya)(ya)。
單臺YDQ系列(lie)高壓(ya)試驗變壓(ya)器的工作(zuo)原理圖見圖2。
單臺YDQ系列交直流(liu)(liu)高壓(ya)(ya)(ya)試驗變壓(ya)(ya)(ya)器的工作(zuo)原(yuan)理圖見圖3,圖中高壓(ya)(ya)(ya)套管中裝(zhuang)有高壓(ya)(ya)(ya)硅(gui)堆,串接在高壓(ya)(ya)(ya)回路(lu)(lu)中作(zuo)半(ban)波整(zheng)流(liu)(liu),以獲得直流(liu)(liu)高電(dian)壓(ya)(ya)(ya)。當用一短路(lu)(lu)桿將高壓(ya)(ya)(ya)硅(gui)堆短接時,可(ke)獲得工頻(pin)高電(dian)壓(ya)(ya)(ya),作(zuo)為交流(liu)(liu)輸出狀(zhuang)態;取消短路(lu)(lu)桿時,作(zuo)為直流(liu)(liu)輸出狀(zhuang)態。
試驗變壓(ya)器高(gao)壓(ya)套管中的高(gao)壓(ya)硅堆未(wei)畫(hua)出(chu),其原理(li)與上圖相(xiang)同。
三(san)臺試(shi)驗(yan)(yan)(yan)變(bian)(bian)(bian)(bian)(bian)壓(ya)(ya)(ya)(ya)(ya)(ya)(ya)器(qi)(qi)串(chuan)級(ji)(ji)獲(huo)得更高(gao)(gao)電(dian)(dian)壓(ya)(ya)(ya)(ya)(ya)(ya)(ya)的(de)(de)(de)(de)接線原理(li)見(jian)圖(tu)4。串(chuan)級(ji)(ji)高(gao)(gao)壓(ya)(ya)(ya)(ya)(ya)(ya)(ya)試(shi)驗(yan)(yan)(yan)變(bian)(bian)(bian)(bian)(bian)壓(ya)(ya)(ya)(ya)(ya)(ya)(ya)器(qi)(qi)有很大(da)的(de)(de)(de)(de)優越性,因為(wei)整(zheng)個(ge)試(shi)驗(yan)(yan)(yan)裝(zhuang)(zhuang)置(zhi)由幾(ji)臺單(dan)(dan)臺試(shi)驗(yan)(yan)(yan)變(bian)(bian)(bian)(bian)(bian)壓(ya)(ya)(ya)(ya)(ya)(ya)(ya)器(qi)(qi)組(zu)(zu)(zu)成(cheng),單(dan)(dan)臺試(shi)驗(yan)(yan)(yan)變(bian)(bian)(bian)(bian)(bian)壓(ya)(ya)(ya)(ya)(ya)(ya)(ya)器(qi)(qi)容量小、電(dian)(dian)壓(ya)(ya)(ya)(ya)(ya)(ya)(ya)低、重量輕(qing),便于運輸和(he)(he)(he)安裝(zhuang)(zhuang)。它(ta)既然可串(chuan)接成(cheng)高(gao)(gao)出(chu)幾(ji)倍的(de)(de)(de)(de)單(dan)(dan)臺試(shi)驗(yan)(yan)(yan)變(bian)(bian)(bian)(bian)(bian)壓(ya)(ya)(ya)(ya)(ya)(ya)(ya)器(qi)(qi)輸出(chu)電(dian)(dian)壓(ya)(ya)(ya)(ya)(ya)(ya)(ya)組(zu)(zu)(zu)合使用,又可分開成(cheng)幾(ji)套單(dan)(dan)臺試(shi)驗(yan)(yan)(yan)變(bian)(bian)(bian)(bian)(bian)壓(ya)(ya)(ya)(ya)(ya)(ya)(ya)器(qi)(qi)單(dan)(dan)獨使用。整(zheng)套裝(zhuang)(zhuang)置(zhi)投資小,經(jing)濟實惠。圖(tu)5中,在(zai)**級(ji)(ji)和(he)(he)(he)**級(ji)(ji)的(de)(de)(de)(de)每個(ge)單(dan)(dan)元試(shi)驗(yan)(yan)(yan)變(bian)(bian)(bian)(bian)(bian)壓(ya)(ya)(ya)(ya)(ya)(ya)(ya)器(qi)(qi)中都有一(yi)個(ge)勵磁(ci)繞(rao)組(zu)(zu)(zu)A1、C1和(he)(he)(he)A2、C2。在(zai)三(san)臺串(chuan)級(ji)(ji)試(shi)驗(yan)(yan)(yan)變(bian)(bian)(bian)(bian)(bian)壓(ya)(ya)(ya)(ya)(ya)(ya)(ya)器(qi)(qi)基(ji)本原理(li)中,低壓(ya)(ya)(ya)(ya)(ya)(ya)(ya)電(dian)(dian)源加在(zai)試(shi)驗(yan)(yan)(yan)變(bian)(bian)(bian)(bian)(bian)壓(ya)(ya)(ya)(ya)(ya)(ya)(ya)器(qi)(qi)Ⅰ的(de)(de)(de)(de)初(chu)(chu)級(ji)(ji)繞(rao)組(zu)(zu)(zu)a1x1上,單(dan)(dan)臺試(shi)驗(yan)(yan)(yan)變(bian)(bian)(bian)(bian)(bian)壓(ya)(ya)(ya)(ya)(ya)(ya)(ya)器(qi)(qi)Ⅰ、Ⅱ、Ⅲ的(de)(de)(de)(de)輸出(chu)電(dian)(dian)壓(ya)(ya)(ya)(ya)(ya)(ya)(ya)都是(shi)V。勵磁(ci)繞(rao)組(zu)(zu)(zu)A1、C1給**級(ji)(ji)試(shi)驗(yan)(yan)(yan)變(bian)(bian)(bian)(bian)(bian)壓(ya)(ya)(ya)(ya)(ya)(ya)(ya)器(qi)(qi)Ⅱ的(de)(de)(de)(de)初(chu)(chu)級(ji)(ji)繞(rao)組(zu)(zu)(zu)供電(dian)(dian);**級(ji)(ji)試(shi)驗(yan)(yan)(yan)變(bian)(bian)(bian)(bian)(bian)壓(ya)(ya)(ya)(ya)(ya)(ya)(ya)器(qi)(qi)Ⅱ的(de)(de)(de)(de)勵磁(ci)繞(rao)組(zu)(zu)(zu)A2、C2給第三(san)級(ji)(ji)試(shi)驗(yan)(yan)(yan)變(bian)(bian)(bian)(bian)(bian)壓(ya)(ya)(ya)(ya)(ya)(ya)(ya)器(qi)(qi)Ⅲ的(de)(de)(de)(de)初(chu)(chu)級(ji)(ji)繞(rao)組(zu)(zu)(zu)供電(dian)(dian)。**級(ji)(ji)試(shi)驗(yan)(yan)(yan)變(bian)(bian)(bian)(bian)(bian)壓(ya)(ya)(ya)(ya)(ya)(ya)(ya)器(qi)(qi)Ⅱ和(he)(he)(he)第三(san)級(ji)(ji)試(shi)驗(yan)(yan)(yan)變(bian)(bian)(bian)(bian)(bian)壓(ya)(ya)(ya)(ya)(ya)(ya)(ya)器(qi)(qi)Ⅲ的(de)(de)(de)(de)箱(xiang)體(ti)分別處在(zai)對(dui)地為(wei)1V和(he)(he)(he)2V的(de)(de)(de)(de)高(gao)(gao)電(dian)(dian)位上,所以箱(xiang)體(ti)對(dui)地是(shi)絕緣(yuan)的(de)(de)(de)(de),試(shi)驗(yan)(yan)(yan)變(bian)(bian)(bian)(bian)(bian)壓(ya)(ya)(ya)(ya)(ya)(ya)(ya)器(qi)(qi)Ⅰ的(de)(de)(de)(de)箱(xiang)體(ti)是(shi)接地的(de)(de)(de)(de)。這(zhe)樣(yang)**級(ji)(ji)、**級(ji)(ji)、第三(san)級(ji)(ji)試(shi)驗(yan)(yan)(yan)變(bian)(bian)(bian)(bian)(bian)壓(ya)(ya)(ya)(ya)(ya)(ya)(ya)器(qi)(qi)對(dui)地的(de)(de)(de)(de)額(e)(e)定(ding)輸出(chu)電(dian)(dian)壓(ya)(ya)(ya)(ya)(ya)(ya)(ya)分別為(wei)1V、2V、3V;其額(e)(e)定(ding)容量分別為(wei)3P、2P、1P。
YDQ系列高壓試驗變(bian)壓器做被試品的工頻耐(nai)壓試驗使用接線原理圖見圖5。
圖中:R1—限流(liu)電(dian)阻 FRC—阻容分壓器 RF—球間隙保護電(dian)阻 G—球間隙 CX—被(bei)試品
注:高壓尾必(bi)須可靠接地
工頻耐壓(ya)試驗中限(xian)流電阻(zu)(zu)R1應(ying)根據試驗變壓(ya)器的(de)額(e)定容量(liang)來選擇。如高(gao)(gao)壓(ya)側(ce)額(e)定輸出電流在(zai)100~300mA時,可取0.5~1Ω/V(試驗電壓(ya));高(gao)(gao)壓(ya)側(ce)額(e)定輸出電流為1A以上時,可取1Ω/V(試驗電壓(ya))。常用(yong)水(shui)電阻(zu)(zu)作(zuo)為限(xian)流電阻(zu)(zu),管子長度可按150kV/m考(kao)慮(lv),管子粗細(xi)應(ying)具有(you)足夠的(de)熱容量(liang)(水(shui)阻(zu)(zu)液配(pei)制方法:用(yong)蒸餾水(shui)加入適量(liang)硫(liu)酸銅配(pei)制成(cheng)各種不(bu)同的(de)阻(zu)(zu)值)。
球間(jian)隙及保護電(dian)阻(zu):當電(dian)壓(ya)超過球間(jian)隙整(zheng)定值時(一般取試驗電(dian)壓(ya)的110%~120%),球間(jian)隙放(fang)電(dian),對被試品(pin)起到保護作用。球間(jian)隙保護電(dian)阻(zu)可按1Ω/V(試驗電(dian)壓(ya))選取。
在工(gong)頻耐(nai)(nai)壓(ya)(ya)(ya)(ya)(ya)(ya)試(shi)驗(yan)中,低電(dian)(dian)(dian)(dian)(dian)壓(ya)(ya)(ya)(ya)(ya)(ya)側測(ce)量電(dian)(dian)(dian)(dian)(dian)壓(ya)(ya)(ya)(ya)(ya)(ya)(儀表電(dian)(dian)(dian)(dian)(dian)壓(ya)(ya)(ya)(ya)(ya)(ya))不是非常準確的(de),其原(yuan)因是由于(yu)試(shi)驗(yan)變(bian)壓(ya)(ya)(ya)(ya)(ya)(ya)器(qi)存(cun)在著漏(lou)抗(kang),在這個漏(lou)抗(kang)上(shang)必(bi)然(ran)存(cun)在著壓(ya)(ya)(ya)(ya)(ya)(ya)降或容升,使試(shi)品(pin)上(shang)的(de)電(dian)(dian)(dian)(dian)(dian)壓(ya)(ya)(ya)(ya)(ya)(ya)低于(yu)或高于(yu)低壓(ya)(ya)(ya)(ya)(ya)(ya)側測(ce)量電(dian)(dian)(dian)(dian)(dian)壓(ya)(ya)(ya)(ya)(ya)(ya)表上(shang)反映出來(lai)的(de)電(dian)(dian)(dian)(dian)(dian)壓(ya)(ya)(ya)(ya)(ya)(ya)。工(gong)頻耐(nai)(nai)壓(ya)(ya)(ya)(ya)(ya)(ya)試(shi)驗(yan)時,被(bei)試(shi)品(pin)上(shang)的(de)電(dian)(dian)(dian)(dian)(dian)壓(ya)(ya)(ya)(ya)(ya)(ya)高于(yu)試(shi)驗(yan)變(bian)壓(ya)(ya)(ya)(ya)(ya)(ya)器(qi)的(de)輸出電(dian)(dian)(dian)(dian)(dian)壓(ya)(ya)(ya)(ya)(ya)(ya),也就(jiu)是所謂容升現象。感應耐(nai)(nai)壓(ya)(ya)(ya)(ya)(ya)(ya)試(shi)驗(yan)時,試(shi)驗(yan)變(bian)壓(ya)(ya)(ya)(ya)(ya)(ya)器(qi)的(de)漏(lou)抗(kang)必(bi)然(ran)存(cun)在著壓(ya)(ya)(ya)(ya)(ya)(ya)降。為(wei)了準確測(ce)量被(bei)試(shi)品(pin)上(shang)所施(shi)加的(de)電(dian)(dian)(dian)(dian)(dian)壓(ya)(ya)(ya)(ya)(ya)(ya),因此(ci)常在高壓(ya)(ya)(ya)(ya)(ya)(ya)側接入FRC阻(zu)容分壓(ya)(ya)(ya)(ya)(ya)(ya)器(qi)來(lai)測(ce)量電(dian)(dian)(dian)(dian)(dian)壓(ya)(ya)(ya)(ya)(ya)(ya)(見圖5)。
工頻耐壓(ya)試驗(yan)操作(zuo)注(zhu)意事項
1)試驗人員應做好分工,明確相互間聯(lian)系方法。并(bing)有(you)專門人監護現場**及觀(guan)察(cha)試品狀態。
2)被試(shi)品(pin)應先清(qing)掃干凈,并**干燥,以(yi)免損壞(huai)被試(shi)品(pin)和(he)試(shi)驗帶來(lai)的誤差。
3)對于(yu)大型試(shi)驗(yan),一般都(dou)應先進行空升試(shi)驗(yan)。即不接試(shi)品時升壓至(zhi)試(shi)驗(yan)電壓,校對各(ge)種表(biao)計(ji),調整球(qiu)間隙。
4)升壓(ya)速度不能太(tai)快,并必須防止突然(ran)加壓(ya)。例如調壓(ya)器不在零位(wei)(wei)時突然(ran)合(he)閘。也不能突然(ran)切斷電源,一般應在調壓(ya)器降至(zhi)零位(wei)(wei)時拉閘。
5)當電(dian)壓(ya)升(sheng)至(zhi)試驗電(dian)壓(ya)時(shi),開(kai)始計時(shi),到(dao)(dao)1min后(hou),迅速降壓(ya)到(dao)(dao)1/3試驗電(dian)壓(ya)以(yi)下(xia)時(shi),才能拉開(kai)電(dian)源。
6)在升壓(ya)或耐(nai)壓(ya)試驗過程中,如發現(xian)下(xia)列不正常情況時,應立即降壓(ya),切斷電源。停止試驗并查明原因:①電壓(ya)表指針擺動很大(da);②發現(xian)絕緣(yuan)燒(shao)焦或冒煙;③被試品內有不正常的聲音。
7)耐壓試(shi)驗前后(hou)應測量絕緣電阻,檢查(cha)絕緣情況。
試驗變(bian)壓(ya)器(qi)在做被試品(pin)的直流(liu)耐(nai)壓(ya)或泄(xie)露試驗時接線原理圖(tu)如圖(tu)6。
注:此試(shi)驗(yan)應先(xian)抽出短路桿“D”,圖6中所(suo)示。
圖中(zhong):VD—高壓(ya)硅堆 R1—限流電阻 C1—高壓(ya)濾波電容(rong) FRC—阻容(rong)分壓(ya)器 CX—被試(shi)品(pin) μA—帶保護微(wei)安表
泄(xie)露試(shi)驗(yan)中限(xian)流(liu)(liu)電(dian)阻(zu)(zu)R1選擇在額定輸出電(dian)壓(ya)時,輸出端短(duan)路電(dian)流(liu)(liu)不超過(guo)高壓(ya)硅堆(dui)的*大整流(liu)(liu)。如電(dian)壓(ya)硅堆(dui)的*大整流(liu)(liu)電(dian)流(liu)(liu)為100mA時用于60kV的試(shi)驗(yan)裝置(zhi)中,限(xian)流(liu)(liu)電(dian)阻(zu)(zu)按R1=60/0.1=600kΩ選擇。限(xian)流(liu)(liu)電(dian)阻(zu)(zu)還應具(ju)有足夠的容量和(he)沿面放(fang)電(dian)距離。
高壓濾波(bo)電容(rong)C1一(yi)般(ban)選擇在0.01~0.1μF,當(dang)被試品的電容(rong)量很大時(shi),C1可省略不用。
泄露試(shi)驗的操作及注意(yi)事項
1)試(shi)驗(yan)前(qian)應先(xian)檢查被(bei)試(shi)品(pin)是否停(ting)電(dian),接地放電(dian),一切對外連線是否擦干凈。要嚴(yan)防將試(shi)驗(yan)電(dian)壓加到有人工作的(de)部(bu)位上去。
2)接(jie)好(hao)試(shi)驗(yan)裝置的(de)接(jie)線(xian)后,應(ying)復查無誤后才可加(jia)壓(ya)(ya)。應(ying)特(te)別注意(yi)檢查高壓(ya)(ya)設(she)備及引線(xian)與地、與操作人員的(de)**距離,被(bei)試(shi)品的(de)外殼是否可靠接(jie)地,要按(an)**規程中所規定的(de)內容進(jin)行試(shi)驗(yan)。
3)對于大電(dian)容(rong)量設備應(ying)緩慢升壓(ya),防止被試品的充(chong)電(dian)電(dian)流燒壞微安表(biao)。必要時應(ying)分級加(jia)壓(ya),分別讀(du)取(qu)各級電(dian)壓(ya)下微安表(biao)的穩定讀(du)數。
4)試驗(yan)過程中,應密切(qie)監視被試品、試驗(yan)裝置、微安(an)表,一旦發生擊穿、閃爍等異常現象應立即降壓(ya),切(qie)斷電源,并查明原因(yin),詳(xiang)細(xi)記錄(lu)。
5)試(shi)驗(yan)完畢,降壓,切斷電(dian)源后應將被試(shi)品及(ji)試(shi)驗(yan)裝置本身充分放電(dian)。
四、WBYD-20KVA/100KV工頻交流試驗變壓器注意事項
1、按照您所進行(xing)的(de)(de)(de)試(shi)驗(yan)(yan)接好(hao)工作(zuo)(zuo)線(xian)路。試(shi)驗(yan)(yan)變(bian)壓器的(de)(de)(de)外殼以及(ji)(ji)操作(zuo)(zuo)系統的(de)(de)(de)外殼必須(xu)可(ke)靠接地(di)。試(shi)驗(yan)(yan)變(bian)壓器高壓繞(rao)組的(de)(de)(de)X端(duan)(duan)(高壓尾)以及(ji)(ji)測量繞(rao)組的(de)(de)(de)F端(duan)(duan)必須(xu)可(ke)靠接地(di)。
2、做串級(ji)(ji)試驗時(shi),**級(ji)(ji)、第三級(ji)(ji)試驗變壓器的(de)低壓繞組(zu)的(de)X端(duan),測量(liang)繞組(zu)的(de)F端(duan)以及高壓繞組(zu)的(de)X端(duan)(高壓尾)均接本級(ji)(ji)試驗變壓器的(de)外殼。**級(ji)(ji)、第三級(ji)(ji)試驗變壓器的(de)外殼必須通(tong)過絕緣支(zhi)架接地(di)。
3、接(jie)通電源前,操作系統(tong)的調壓器必須調到零位后方可接(jie)通電源,合閘(zha),開始(shi)升壓。
4、從零(ling)開始均勻(yun)旋轉(zhuan)調壓(ya)器手(shou)輪升(sheng)(sheng)(sheng)(sheng)壓(ya)。升(sheng)(sheng)(sheng)(sheng)壓(ya)方法(fa)(fa)(fa)有(you):快速(su)(su)升(sheng)(sheng)(sheng)(sheng)壓(ya)法(fa)(fa)(fa),即(ji)20s逐(zhu)級升(sheng)(sheng)(sheng)(sheng)壓(ya)法(fa)(fa)(fa);慢(man)速(su)(su)升(sheng)(sheng)(sheng)(sheng)壓(ya)法(fa)(fa)(fa),即(ji)60s逐(zhu)級升(sheng)(sheng)(sheng)(sheng)壓(ya)法(fa)(fa)(fa);極慢(man)速(su)(su)升(sheng)(sheng)(sheng)(sheng)壓(ya)法(fa)(fa)(fa)供選用。電(dian)壓(ya)從零(ling)開始按一(yi)定(ding)的升(sheng)(sheng)(sheng)(sheng)壓(ya)方式和速(su)(su)度上升(sheng)(sheng)(sheng)(sheng)到您所(suo)(suo)需(xu)的額定(ding)試(shi)(shi)驗(yan)電(dian)壓(ya)的75%后(hou),在以每秒2%額定(ding)試(shi)(shi)驗(yan)電(dian)壓(ya)的速(su)(su)度升(sheng)(sheng)(sheng)(sheng)到您所(suo)(suo)需(xu)的額定(ding)電(dian)壓(ya),并密(mi)切注意測量儀(yi)表的指示(shi)以及被(bei)試(shi)(shi)品的情(qing)況(kuang)。升(sheng)(sheng)(sheng)(sheng)壓(ya)過程中或(huo)試(shi)(shi)驗(yan)過程中如發現(xian)測量儀(yi)表的指示(shi)及被(bei)試(shi)(shi)品情(qing)況(kuang)異常(chang),應立即(ji)降壓(ya),切斷電(dian)源,查明情(qing)況(kuang)。
5、試驗完(wan)畢后,應在數秒內勻(yun)速的將調壓器(qi)返回(hui)至零位,然后切(qie)斷電源。
6、本產品不得超過額定參數使用。除試驗必須外,決(jue)不允許(xu)全電壓通電或斷電。
7、再升壓(ya)或耐壓(ya)試驗(yan)過程中,如發現(xian)以(yi)下(xia)不正常情況時,應(ying)立即降壓(ya),切斷電源,停止(zhi)試驗(yan)并查明原因。
⑴電(dian)壓表指針(zhen)擺動(或數字(zi)跳動)很大(da)
⑵電流表直線上升
被試品(pin)內有不正常的聲音
8、圖1中第(di)9項系壓力閥及壓力表,為(wei)長期關閉狀態。每6個月開閥一次,以檢查SF6壓力,應(ying)不小于0.2MPa(檢查壓力后立即關閉閥門),低于0.2MPa時應(ying)加(jia)(jia)SF6氣體(ti),以增(zeng)加(jia)(jia)氣絕緣(yuan)。
9、耐壓實驗前后(hou)應測量(liang)被(bei)試設備的(de)絕緣(yuan)電(dian)阻,檢查絕緣(yuan)情況。
10、當試(shi)驗變(bian)壓器長(chang)期不(bu)使用時,應放置(zhi)于通風、干燥、無陽光直射的地方。
11、該產品不允許在高于45℃的(de)溫度下長期存放、使用、放氣(qi)。
12、運(yun)(yun)輸(shu)搬運(yun)(yun)途中不得重(zhong)力沖擊。
13、產(chan)品緊固(gu)件(jian)及壓(ya)力(li)閥(fa)、壓(ya)力(li)表不得擅自松動(dong)。
14、使用本產品做高(gao)壓(ya)(ya)試驗時,出(chu)熟悉本說明書外,還必(bi)須嚴格執行國(guo)家有關(guan)標準(zhun)和操作(zuo)規(gui)程。可(ke)參照GB311-83《高(gao)壓(ya)(ya)輸變設備的絕(jue)緣配合,高(gao)壓(ya)(ya)試驗技術(shu)》;《電氣設備預防(fang)性試驗規(gui)程》等(deng)。
五、WBYD-20KVA/100KV工頻交流試驗變壓器容量選擇
標稱(cheng)試驗變壓(ya)器容(rong)量Pn的確定公式:Pn=kVn 2ωCt×10-9
式中:
Pn——標(biao)稱(cheng)試(shi)驗變壓(ya)器(qi)容量(kVA)
Vn——試驗變壓器的(de)額定輸出高壓的(de)有效值(kV)
k ——**系數。k≥1,標稱電壓(ya)Vn≥1MV時,k=2;標稱電壓(ya)較低時,k值可取高一些。
Ct——被試品的電容(rong)量(pF)
ω——角(jiao)頻(pin)率(lv),ω=2πf, f——試(shi)驗電源的頻(pin)率(lv)
被試設備的電容量(liang)Ct可由交流(liu)電橋測出。Ct的變化很大,
可(ke)由設(she)備的類(lei)型而(er)定。
典型數據如下:
簡單(dan)的棒式或懸式絕(jue)緣子 幾十微法
簡單的分級套管(guan) 100~1000pF
電壓互感器 200 ~ 500pF
電力變壓器 < 1000kVA ~1000pF
> 1000kVA 1000~10000pF
高壓(ya)電力電纜和油浸(jin)紙(zhi)絕緣 250~300pF/m
氣體絕(jue)緣 ~60pF/m
封閉變電站,SF6氣體(ti)絕緣(yuan) 100~10000Pf;
對于不同(tong)的試驗(yan)電(dian)壓Vn,選擇不同(tong)的(適當的)**系數k。
以(yi)下列出不同(tong)的(de)Vn所選用的(de)k值供(gong)參考。
Vn =50~100kV k = 4
Vn =150~300kV k = 3
Vn > 300kV k = 2