工頻耐壓試驗變壓器使用方法：

工頻耐(nai)壓試驗中限流電(dian)阻R1應(ying)根據試驗變壓器的(de)(de)額定(ding)(ding)(ding)容量來選擇。如高壓側(ce)(ce)額定(ding)(ding)(ding)輸出(chu)電(dian)流在 100-300MA時，可取(qu)0.5-1Ω/V（試驗電(dian)壓）；高壓側(ce)(ce)額定(ding)(ding)(ding)輸出(chu)電(dian)流為1A以上時，可取(qu)1Ω/V（試驗電(dian)壓）。常用水電(dian)陰作為限流電(dian)阻，管(guan)(guan)于(yu)長度可按150KV/m考慮，管(guan)(guan)子(zi)和粗細應(ying)具有足夠的(de)(de)熱容量（水阻液配制(zhi)方法：用蒸餾水加入(ru)適量硫酸(suan)銅配制(zhi)成各種不同的(de)(de)陰值）。

球(qiu)間(jian)隙(xi)及保(bao)護(hu)電阻：當(dang)電壓(ya)(ya)超過球(qiu)間(jian)隙(xi)整定值時（一般取(qu)試(shi)(shi)驗電壓(ya)(ya)的110%-120%）球(qiu)間(jian)隙(xi)放電，對(dui)被試(shi)(shi)品起到保(bao)護(hu)作用。球(qiu)間(jian)隙(xi)保(bao)護(hu)電阻可按1Ω/V（試(shi)(shi)驗電壓(ya)(ya)）選(xuan)取(qu)。

在(zai)工頻耐(nai)(nai)壓(ya)(ya)試(shi)(shi)(shi)(shi)驗(yan)中，低(di)(di)壓(ya)(ya)側測量電(dian)(dian)壓(ya)(ya)（儀表電(dian)(dian)壓(ya)(ya)）不是(shi)非常(chang)準確的(de)(de)，其原因(yin)是(shi)由(you)于(yu)試(shi)(shi)(shi)(shi)驗(yan)變壓(ya)(ya)器(qi)存(cun)在(zai)著漏抗，在(zai)這上個漏抗上必(bi)然存(cun)在(zai)著壓(ya)(ya)降或容(rong)(rong)升，使(shi)試(shi)(shi)(shi)(shi)品(pin)上的(de)(de)電(dian)(dian)壓(ya)(ya)低(di)(di)于(yu)或高于(yu)低(di)(di)壓(ya)(ya)側測量電(dian)(dian)壓(ya)(ya)表上反(fan)映出來的(de)(de)電(dian)(dian)壓(ya)(ya)。工頻耐(nai)(nai)壓(ya)(ya)試(shi)(shi)(shi)(shi)驗(yan)時，被試(shi)(shi)(shi)(shi)品(pin)上的(de)(de)電(dian)(dian)壓(ya)(ya)高于(yu)試(shi)(shi)(shi)(shi)驗(yan)變壓(ya)(ya)器(qi)的(de)(de)輸出電(dian)(dian)壓(ya)(ya)，也就是(shi)所謂容(rong)(rong)升現象。感(gan)應耐(nai)(nai)壓(ya)(ya)試(shi)(shi)(shi)(shi)驗(yan)時。試(shi)(shi)(shi)(shi)驗(yan)變壓(ya)(ya)器(qi)的(de)(de)漏抗必(bi)須存(cun)在(zai)著壓(ya)(ya)降。為了準確測量被試(shi)(shi)(shi)(shi)品(pin)上所施加電(dian)(dian)壓(ya)(ya)，因(yin)此常(chang)在(zai)高壓(ya)(ya)側接入RCF阻(zu)容(rong)(rong)分壓(ya)(ya)器(qi)來測量電(dian)(dian)壓(ya)(ya)。

工頻耐壓(ya)試驗(yan)(yan)(yan)變壓(ya)器(qi)是(shi)根據國家行(xing)(xing)業(ye)試驗(yan)(yan)(yan)標(biao)準而設(she)計(ji)的(de)(de)試驗(yan)(yan)(yan)設(she)備，其安全可靠、功能強(qiang)大、使用方便(bian)、維護(hu)簡(jian)單，主要(yao)(yao)用于對各種電(dian)(dian)(dian)器(qi)產(chan)(chan)品、電(dian)(dian)(dian)氣元(yuan)件、絕緣(yuan)材料(liao)等(deng)進行(xing)(xing)規(gui)定電(dian)(dian)(dian)壓(ya)下(xia)的(de)(de)絕緣(yuan)強(qiang)度試驗(yan)(yan)(yan)，以考核(he)產(chan)(chan)品的(de)(de)絕緣(yuan)水平，發現被試品的(de)(de)絕緣(yuan)缺陷，衡量過電(dian)(dian)(dian)壓(ya)的(de)(de)能力，是(shi)電(dian)(dian)(dian)力運行(xing)(xing)相(xiang)關部門、電(dian)(dian)(dian)工電(dian)(dian)(dian)器(qi)制造企業(ye)、冶金、煤(mei)礦(kuang)、電(dian)(dian)(dian)氣化(hua)鐵(tie)路相(xiang)關部門、科研單位及高等(deng)院校等(deng)需要(yao)(yao)耐壓(ya)試驗(yan)(yan)(yan)設(she)備的(de)(de)產(chan)(chan)品。

特(te)點:

1)電壓(ya)高：試(shi)(shi)驗(yan)(yan)變(bian)壓(ya)器的(de)一次電壓(ya)為220V或380V，但單臺試(shi)(shi)驗(yan)(yan)變(bian)壓(ya)器二(er)次電壓(ya)則(ze)常達數千伏至(zhi)數萬(wan)伏。二(er)次電壓(ya)超(chao)過750kV的(de)試(shi)(shi)驗(yan)(yan)變(bian)壓(ya)器，通常采用(yong)多(duo)臺串(chuan)級(ji)式結構。

2)電(dian)流小：試(shi)驗(yan)變壓器的額定(ding)電(dian)流實際(ji)上是被試(shi)品的電(dian)容電(dian)流，所以一般(ban)小于1A。但用于電(dian)纜和大(da)型電(dian)機試(shi)驗(yan)、外絕緣污穢(hui)試(shi)驗(yan)、線路電(dian)暈試(shi)驗(yan)等(deng)項目的試(shi)驗(yan)變壓器，二次電(dian)流可達數安(an)。

3)工作時(shi)間短：因被試(shi)(shi)產品的耐壓(ya)時(shi)間短，所(suo)以試(shi)(shi)驗(yan)(yan)(yan)變(bian)壓(ya)器除了用于外絕(jue)緣污(wu)穢(hui)試(shi)(shi)驗(yan)(yan)(yan)、線路電(dian)(dian)暈試(shi)(shi)驗(yan)(yan)(yan)、電(dian)(dian)纜試(shi)(shi)驗(yan)(yan)(yan)外，一般均為0.5h或1h的短時(shi)工作制。

4)試驗變壓(ya)器一般為單相、戶內裝(zhuang)置(zhi)（也有做成戶外裝(zhuang)置(zhi)的）：均為油浸(jin)自冷式(shi)結構，繞(rao)組絕緣層較厚，高壓(ya)繞(rao)組通(tong)常(chang)一端(duan)接地。

技術要求:

①輸(shu)出電(dian)壓(ya)(ya)波(bo)形(xing)。試驗(yan)變壓(ya)(ya)器(qi)(qi)輸(shu)出電(dian)壓(ya)(ya)波(bo)形(xing)應(ying)盡量接近(jin)正弦波(bo)。為了減少由于(yu)空載電(dian)流的(de)諧波(bo)分量通(tong)過調壓(ya)(ya)器(qi)(qi)和變壓(ya)(ya)器(qi)(qi)的(de)阻抗后(hou)，產生(sheng)諧波(bo)電(dian)壓(ya)(ya)而引(yin)起電(dian)壓(ya)(ya)波(bo)形(xing)畸(ji)變，磁通(tong)密度應(ying)選在(zai)鐵心(xin)磁化曲線(xian)的(de)直線(xian)段；同時(shi)要(yao)選用波(bo)形(xing)畸(ji)變小的(de)調壓(ya)(ya)設(she)備，必要(yao)時(shi)可加設(she)濾波(bo)裝置(zhi)。

②阻(zu)(zu)抗電(dian)壓(ya)。試(shi)(shi)驗(yan)(yan)變(bian)壓(ya)器(qi)的二次電(dian)流(liu)(liu)一(yi)般為容性電(dian)流(liu)(liu)，當(dang)二次電(dian)流(liu)(liu)流(liu)(liu)經調(diao)壓(ya)器(qi)和試(shi)(shi)驗(yan)(yan)變(bian)壓(ya)器(qi)的阻(zu)(zu)抗時(shi)，將導致(zhi)輸出電(dian)壓(ya)超過由電(dian)壓(ya)比所(suo)確定(ding)的數值，所(suo)以試(shi)(shi)驗(yan)(yan)變(bian)壓(ya)器(qi)的阻(zu)(zu)抗電(dian)壓(ya)不宜太大(da)，否則(ze)可能影響測試(shi)(shi)結果的準(zhun)確性，同時(shi)還(huan)會降低試(shi)(shi)驗(yan)(yan)設備的短路容量。但如阻(zu)(zu)抗電(dian)壓(ya)太小，被(bei)試(shi)(shi)品擊穿或閃(shan)絡時(shi)，短路電(dian)流(liu)(liu)可能增大(da)。單臺試(shi)(shi)驗(yan)(yan)變(bian)壓(ya)器(qi)的阻(zu)(zu)抗電(dian)壓(ya)一(yi)般為4.5~10%，組成多(duo)臺串級時(shi)，則(ze)可達30~40%