?近(jin)年(nian)來，對于(yu)現(xian)場的高(gao)電壓(ya)被試變(bian)壓(ya)器，有的單位也采用(yong)串聯諧振(zhen)耐壓試驗裝置來完成(cheng)工頻耐壓(ya)(ya)(ya)試驗(yan)。串聯諧(xie)振(zhen)(zhen)法(fa)工頻耐壓(ya)(ya)(ya)試驗(yan)是通過(guo)調節回路(lu)(lu)(lu)中的電(dian)(dian)(dian)(dian)感、電(dian)(dian)(dian)(dian)容(rong)或頻率(lv)使電(dian)(dian)(dian)(dian)感與電(dian)(dian)(dian)(dian)容(rong)處于(yu)串聯諧(xie)振(zhen)(zhen)狀態，即(ji)oL=1/aC.此時在電(dian)(dian)(dian)(dian)感和電(dian)(dian)(dian)(dian)容(rong)上的電(dian)(dian)(dian)(dian)壓(ya)(ya)(ya)可大(da)(da)大(da)(da)超出(chu)回路(lu)(lu)(lu)外加電(dian)(dian)(dian)(dian)壓(ya)(ya)(ya)，實現低電(dian)(dian)(dian)(dian)壓(ya)(ya)(ya)、小容(rong)量電(dian)(dian)(dian)(dian)源(yuan)使被試電(dian)(dian)(dian)(dian)氣設備的絕緣(yuan)承(cheng)受高電(dian)(dian)(dian)(dian)壓(ya)(ya)(ya)考驗(yan)的目的。流(liu)過(guo)高壓(ya)(ya)(ya)回路(lu)(lu)(lu)的電(dian)(dian)(dian)(dian)流(liu)，在諧(xie)振(zhen)(zhen)狀態時達到(dao)最大(da)(da)值，即(ji)Imax=U/R。式中，U為試驗(yan)變(bian)壓(ya)(ya)(ya)器(qi)輸出(chu)電(dian)(dian)(dian)(dian)壓(ya)(ya)(ya)，R為高壓(ya)(ya)(ya)回路(lu)(lu)(lu)等效電(dian)(dian)(dian)(dian)阻。試驗(yan)回路(lu)(lu)(lu)中諧(xie)振(zhen)(zhen)回路(lu)(lu)(lu)的品質(zhi)因(yin)數Q=oL/R，被試變(bian)壓(ya)(ya)(ya)器(qi)Cx(試品電(dian)(dian)(dian)(dian)容(rong))上的電(dian)(dian)(dian)(dian)壓(ya)(ya)(ya)UC=QU。由于(yu)Q值遠大(da)(da)于(yu)1，則(ze)U遠小于(yu)UC，因(yin)此，試驗(yan)變(bian)壓(ya)(ya)(ya)器(qi)和調壓(ya)(ya)(ya)器(qi)的容(rong)量也相應可小Q倍。

??串聯諧振法工(gong)頻(pin)(pin)耐(nai)壓(ya)(ya)試(shi)(shi)驗(yan)所用(yong)的試(shi)(shi)驗(yan)裝(zhuang)置(zhi)一(yi)般有調頻(pin)(pin)式和調容(rong)式，額(e)定(ding)輸(shu)出(chu)電(dian)壓(ya)(ya)為(wei)150， 200， 250， 300kV， 輸(shu)出(chu)容(rong)量(liang)為(wei) 50， 100， 150，200kVA，總重量(liang)為(wei) 200~300kg，由(you)(you)于(yu)串聯諧振耐(nai)壓(ya)(ya)試(shi)(shi)驗(yan)裝(zhuang)置(zhi)由(you)(you)試(shi)(shi)驗(yan)變壓(ya)(ya)器(qi)、電(dian)感、電(dian)容(rong)、調壓(ya)(ya)器(qi)等(deng)幾部分組成(cheng)，單件(jian)重量(liang)大大減(jian)輕，適用(yong)于(yu)工(gong)程(cheng)施工(gong)現場的高電(dian)壓(ya)(ya)工(gong)頻(pin)(pin)耐(nai)壓(ya)(ya)試(shi)(shi)驗(yan)。

??試(shi)(shi)驗(yan)前(qian)應(ying)將(jiang)與被(bei)(bei)試(shi)(shi)品連接(jie)的電子元件及(ji)其它不能承受(shou)相應(ying)試(shi)(shi)驗(yan)電壓的元件斷開，例如(ru)避雷器(qi)(qi)、浪(lang)涌保護器(qi)(qi)、溫度控制器(qi)(qi)等，對(dui)母線上未拆(chai)除(chu)的電流互感器(qi)(qi)，其二(er)次側應(ying)可靠短接(jie)。將(jiang)被(bei)(bei)試(shi)(shi)品的外殼和非被(bei)(bei)試(shi)(shi)繞組(zu)可靠接(jie)地。高壓試(shi)(shi)驗(yan)變壓器(qi)(qi)與被(bei)(bei)試(shi)(shi)品應(ying)保持(chi)清潔，對(dui)油浸(jin)變，油位(wei)偏低(di)時(shi)應(ying)補充(chong)合格的同(tong)型號(hao)變壓器(qi)(qi)油。對(dui)補油的的被(bei)(bei)試(shi)(shi)品，應(ying)按規定使(shi)油靜止一定時(shi)間再加(jia)壓，對(dui) 110kV 及(ji)以下的充(chong)油電力(li)設備，在(zai)注滿油后靜置(zhi)時(shi)間應(ying)不少于24h，對(dui) 220kV及(ji)330kV的充(chong)油電力(li)設備，靜置(zhi)時(shi)間應(ying)不少于48h。

??在進(jin)行工頻耐壓(ya)(ya)試(shi)(shi)驗(yan)(yan)(yan)時，高(gao)壓(ya)(ya)試(shi)(shi)驗(yan)(yan)(yan)變(bian)(bian)壓(ya)(ya)器的(de)(de)(de)(de)高(gao)壓(ya)(ya)輸出(chu)端應接保(bao)護電(dian)(dian)(dian)阻(zu)R1，見圖1，以(yi)限制(zhi)被(bei)試(shi)(shi)品擊穿時高(gao)壓(ya)(ya)試(shi)(shi)驗(yan)(yan)(yan)變(bian)(bian)壓(ya)(ya)器高(gao)壓(ya)(ya)側短(duan)路電(dian)(dian)(dian)流，降低(di)試(shi)(shi)驗(yan)(yan)(yan)變(bian)(bian)壓(ya)(ya)器高(gao)壓(ya)(ya)線(xian)圈上的(de)(de)(de)(de)過(guo)電(dian)(dian)(dian)壓(ya)(ya)。試(shi)(shi)品擊穿后的(de)(de)(de)(de)短(duan)路電(dian)(dian)(dian)流大小僅由(you)試(shi)(shi)驗(yan)(yan)(yan)變(bian)(bian)壓(ya)(ya)器和電(dian)(dian)(dian)源的(de)(de)(de)(de)阻(zu)抗(kang)電(dian)(dian)(dian)壓(ya)(ya)決定(ding)(ding)，一(yi)般(ban)(ban)阻(zu)抗(kang)電(dian)(dian)(dian)壓(ya)(ya)較低(di)，若為5%~10%左(zuo)右(you)，則(ze)短(duan)路電(dian)(dian)(dian)流可能會達(da)到(dao)額定(ding)(ding)電(dian)(dian)(dian)流的(de)(de)(de)(de)20~10倍。因此需要在試(shi)(shi)驗(yan)(yan)(yan)變(bian)(bian)壓(ya)(ya)器和試(shi)(shi)品之間接入保(bao)護電(dian)(dian)(dian)阻(zu)以(yi)限制(zhi)過(guo)大的(de)(de)(de)(de)短(duan)路電(dian)(dian)(dian)流，同時也對擊穿引起的(de)(de)(de)(de)電(dian)(dian)(dian)壓(ya)(ya)振蕩進(jin)行抑制(zhi)。保(bao)護電(dian)(dian)(dian)阻(zu)R1一(yi)般(ban)(ban)為金屬的(de)(de)(de)(de)，也有用(yong)水阻(zu)的(de)(de)(de)(de)，其電(dian)(dian)(dian)阻(zu)值一(yi)般(ban)(ban)取0.1~0.5UN(試(shi)(shi)驗(yan)(yan)(yan)變(bian)(bian)壓(ya)(ya)器二次側的(de)(de)(de)(de)額定(ding)(ding)電(dian)(dian)(dian)壓(ya)(ya)V)。

??電阻(zu)(zu)(zu)R2是直(zhi)接與球隙相串聯的(de)(de)起著阻(zu)(zu)(zu)尼作(zuo)用(yong)的(de)(de)純電阻(zu)(zu)(zu)，一般采用(yong)水(shui)阻(zu)(zu)(zu)。當球隙放電時(shi)，全部電壓降落(luo)在(zai)水(shui)阻(zu)(zu)(zu)上，為了防止(zhi)閃絡，水(shui)阻(zu)(zu)(zu)的(de)(de)長度應滿足耐受(shou)最大試(shi)驗電壓，采用(yong)樹脂或瓷質的(de)(de)水(shui)阻(zu)(zu)(zu)管時(shi)，其長度按每 1000mm能承受(shou) 150kV考慮，為了防止(zhi)試(shi)驗過程(cheng)中水(shui)阻(zu)(zu)(zu)溫度升高和破裂(lie)，水(shui)阻(zu)(zu)(zu)直(zhi)徑應大一些，并(bing)在(zai)頂部開(kai)放氣孔。

??變(bian)壓(ya)(ya)(ya)(ya)器工頻耐壓(ya)(ya)(ya)(ya)試(shi)(shi)驗(yan)(yan)中，由于試(shi)(shi)品(pin)變(bian)壓(ya)(ya)(ya)(ya)器為容(rong)(rong)性(xing)負(fu)載，試(shi)(shi)驗(yan)(yan)變(bian)壓(ya)(ya)(ya)(ya)器的(de)(de)(de)(de)高壓(ya)(ya)(ya)(ya)繞組與試(shi)(shi)品(pin)電(dian)容(rong)(rong)連接，流過(guo)電(dian)容(rong)(rong)性(xing)負(fu)載的(de)(de)(de)(de)容(rong)(rong)性(xing)電(dian)流在(zai)試(shi)(shi)驗(yan)(yan)變(bian)壓(ya)(ya)(ya)(ya)器的(de)(de)(de)(de)漏抗(kang)上會(hui)產生壓(ya)(ya)(ya)(ya)降，由于試(shi)(shi)品(pin)上的(de)(de)(de)(de)電(dian)壓(ya)(ya)(ya)(ya)與試(shi)(shi)驗(yan)(yan)變(bian)壓(ya)(ya)(ya)(ya)器漏抗(kang)上的(de)(de)(de)(de)電(dian)壓(ya)(ya)(ya)(ya)相位相反，使試(shi)(shi)品(pin)上的(de)(de)(de)(de)電(dian)壓(ya)(ya)(ya)(ya)超出(chu)試(shi)(shi)驗(yan)(yan)變(bian)壓(ya)(ya)(ya)(ya)器的(de)(de)(de)(de)輸(shu)出(chu)電(dian)壓(ya)(ya)(ya)(ya)，這種現(xian)(xian)象稱為容(rong)(rong)升現(xian)(xian)象，試(shi)(shi)品(pin)的(de)(de)(de)(de)電(dian)容(rong)(rong)值越(yue)(yue)大，容(rong)(rong)升現(xian)(xian)象越(yue)(yue)明(ming)顯。按照試(shi)(shi)驗(yan)(yan)導則JB/T501-2006的(de)(de)(de)(de)規定，應采(cai)用球隙(xi)或電(dian)容(rong)(rong)分壓(ya)(ya)(ya)(ya)器在(zai)試(shi)(shi)驗(yan)(yan)變(bian)壓(ya)(ya)(ya)(ya)器的(de)(de)(de)(de)高壓(ya)(ya)(ya)(ya)輸(shu)出(chu)端測(ce)量。如果(guo)在(zai)試(shi)(shi)驗(yan)(yan)變(bian)壓(ya)(ya)(ya)(ya)器的(de)(de)(de)(de)低(di)(di)壓(ya)(ya)(ya)(ya)側測(ce)量，則試(shi)(shi)品(pin)上所施加的(de)(de)(de)(de)試(shi)(shi)驗(yan)(yan)電(dian)壓(ya)(ya)(ya)(ya)會(hui)比低(di)(di)壓(ya)(ya)(ya)(ya)側的(de)(de)(de)(de)讀數高一些(xie)。